Hypersonic Weapons: Background and Issues for Congress

Changes from March 17, 2022 to May 5, 2022

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Hypersonic Weapons:
~~March 17~~May 5, 2022 , 2022
Background and Issues for Congress
Kelley M. Sayler
The United States has actively pursued the development of hypersonic weapons— The United States has actively pursued the development of hypersonic weapons—
maneuvering Analyst in Advanced Analyst in Advanced
~~maneuvering~~ weapons that fly at speeds of at least Mach 5—as a part of its conventional weapons that fly at speeds of at least Mach 5—as a part of its conventional
prompt global strike Technology and Global Technology and Global
~~prompt global strike~~ program since the early 2000s. In recent years, the United States program since the early 2000s. In recent years, the United States
~~Security~~
has focused such efforts on has focused such efforts on Security developing hypersonic glide vehicles, which are launched developing hypersonic glide vehicles, which are launched

from a rocket before gliding to a from a rocket before gliding to a target, and hypersonic cruise missiles, which are target, and hypersonic cruise missiles, which are

powered by high-speed, air-breathing engines during flight. As former Vice Chairman of powered by high-speed, air-breathing engines during flight. As former Vice Chairman of
the Joint Chiefs of Staff and former Commander of the Joint Chiefs of Staff and former Commander of U.S. Strategic Command General John Hyten has stated, these U.S. Strategic Command General John Hyten has stated, these
weapons could enable “responsive, long-range, strike options against distant, defended, and/or time-critical weapons could enable “responsive, long-range, strike options against distant, defended, and/or time-critical
threats [such as road-mobile missiles] when other forces are unavailable, denied access, or not preferred.” Critics, threats [such as road-mobile missiles] when other forces are unavailable, denied access, or not preferred.” Critics,
on the other hand, contend that hypersonic weapons lack defined mission requirements, contribute little to U.S. on the other hand, contend that hypersonic weapons lack defined mission requirements, contribute little to U.S.
military capability, and are unnecessary for deterrence. military capability, and are unnecessary for deterrence.
Funding for hypersonic weapons has been relatively restrained in the past; however, both the Pentagon and Funding for hypersonic weapons has been relatively restrained in the past; however, both the Pentagon and
Congress have shown a growing interest in pursuing the development and near-term deployment of hypersonic Congress have shown a growing interest in pursuing the development and near-term deployment of hypersonic
systems. This is due, in part, to the advances in these technologies in Russia and China, both of which have a systems. This is due, in part, to the advances in these technologies in Russia and China, both of which have a
number of hypersonic weapons programs and have likely fielded operational hypersonic glide vehicles—number of hypersonic weapons programs and have likely fielded operational hypersonic glide vehicles—
potentially armed with nuclear warheads. Most U.S. hypersonic weapons, in contrast to those in Russia and potentially armed with nuclear warheads. Most U.S. hypersonic weapons, in contrast to those in Russia and
China, are not being designed for use with a nuclear warhead. As a result, U.S. hypersonic weapons will likely China, are not being designed for use with a nuclear warhead. As a result, U.S. hypersonic weapons will likely
require greater accuracy and will be more technically challenging to develop than nuclear-armed Chinese and require greater accuracy and will be more technically challenging to develop than nuclear-armed Chinese and
Russian systems. Russian systems.
The Pentagon’s The Pentagon’s ~~FY2022~~FY2023 budget request for hypersonic research is $ budget request for hypersonic research is $~~3.8~~4.7 billion—up from $3. billion—up from $3.28 billion in the billion in the
~~FY2021~~FY2022 request. The Missile Defense Agency additionally requested $ request. The Missile Defense Agency additionally requested $~~247.9~~225.5 million for hypersonic defense. At million for hypersonic defense. At
present, the Department of Defense (DOD) has not established any programs of record for hypersonic weapons, present, the Department of Defense (DOD) has not established any programs of record for hypersonic weapons,
suggesting that it may not have approved either mission requirements for the systems or long-term funding plans. suggesting that it may not have approved either mission requirements for the systems or long-term funding plans.
Indeed, as Principal Director for Hypersonics (Office of the Under Secretary of Defense for Research and Indeed, as Principal Director for Hypersonics (Office of the Under Secretary of Defense for Research and
Engineering) Mike White has stated, DOD has not yet made a decision to acquire hypersonic weapons and is Engineering) Mike White has stated, DOD has not yet made a decision to acquire hypersonic weapons and is
instead developing prototypes to assist in the evaluation of potential weapon system concepts and mission sets. instead developing prototypes to assist in the evaluation of potential weapon system concepts and mission sets.
As Congress reviews the Pentagon’s plans for U.S. hypersonic weapons programs, it might consider questions As Congress reviews the Pentagon’s plans for U.S. hypersonic weapons programs, it might consider questions
about the rationale for hypersonic weapons, their expected costs, and their implications for strategic stability and about the rationale for hypersonic weapons, their expected costs, and their implications for strategic stability and
arms control. Potential questions include the following: arms control. Potential questions include the following:
 What mission(s) will hypersonic weapons be used for? Are hypersonic weapons the most cost-  What mission(s) will hypersonic weapons be used for? Are hypersonic weapons the most cost-
effective effective means of executing these potential missions? How will they be incorporated into joint means of executing these potential missions? How will they be incorporated into joint
operational doctrine and concepts? operational doctrine and concepts?
 Given the lack of defined mission requirements for hypersonic weapons, how should Congress  Given the lack of defined mission requirements for hypersonic weapons, how should Congress
evaluate evaluate funding requests for hypersonic weapons programs or the balance of funding requests funding requests for hypersonic weapons programs or the balance of funding requests
for hypersonic weapons programs, enabling technologies, and supporting test infrastructure? Is an for hypersonic weapons programs, enabling technologies, and supporting test infrastructure? Is an
acceleration of research on hypersonic weapons, enabling technologies, or hypersonic missile acceleration of research on hypersonic weapons, enabling technologies, or hypersonic missile
defense options both necessary and technologically feasible? defense options both necessary and technologically feasible?
 How, if at all, will the fielding of hypersonic weapons affect strategic stability?  How, if at all, will the fielding of hypersonic weapons affect strategic stability?
 Is there a need for risk-mitigation measures, such as expanding New START, negotiating new  Is there a need for risk-mitigation measures, such as expanding New START, negotiating new
multilateral ~~multilateral~~ arms control agreements, or undertaking transparency and confidence-building arms control agreements, or undertaking transparency and confidence-building
activities? activities?

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Hypersonic Weapons: Background and Issues for Congress

Introduction
The United States has actively pursued the development of hypersonic weapons as a part of its The United States has actively pursued the development of hypersonic weapons as a part of its
conventional prompt global strike (CPGS) program since the early 2000s.1 In recent years, it has conventional prompt global strike (CPGS) program since the early 2000s.1 In recent years, it has
focused such efforts on hypersonic glide vehicles and hypersonic cruise missiles with shorter and focused such efforts on hypersonic glide vehicles and hypersonic cruise missiles with shorter and
intermediate ranges for use in regional conflicts. Although funding for these programs has been intermediate ranges for use in regional conflicts. Although funding for these programs has been
relatively restrained in the past, both the Pentagon and Congress have shown a growing interest in relatively restrained in the past, both the Pentagon and Congress have shown a growing interest in
pursuing the development and near-term deployment of hypersonic systems. This is due, in part, pursuing the development and near-term deployment of hypersonic systems. This is due, in part,
to advances in these technologies in Russia and China, leading to a heightened focus in the to advances in these technologies in Russia and China, leading to a heightened focus in the
United States on the strategic threat posed by hypersonic flight. Open-source reporting indicates United States on the strategic threat posed by hypersonic flight. Open-source reporting indicates
that both China and Russia have conducted numerous successful tests of hypersonic glide that both China and Russia have conducted numerous successful tests of hypersonic glide
vehicles and likely fielded an operational capability. vehicles and likely fielded an operational capability.
Experts disagree on the potential impact of competitor hypersonic weapons on both strategic Experts disagree on the potential impact of competitor hypersonic weapons on both strategic
stability and the U.S. military’s competitive advantage. Nevertheless, former Under Secretary of stability and the U.S. military’s competitive advantage. Nevertheless, former Under Secretary of
Defense for Research and Engineering (USD[R&E]) Michael Griffin has testified to Congress Defense for Research and Engineering (USD[R&E]) Michael Griffin has testified to Congress
that the United States does not “have systems which can hold [China and Russia] at risk in a that the United States does not “have systems which can hold [China and Russia] at risk in a
corresponding manner, and we don’t have defenses against [their] systems.”2 Although the John corresponding manner, and we don’t have defenses against [their] systems.”2 Although the John
S. McCain National Defense Authorization Act for Fiscal Year 2019 (FY2019 NDAA, P.L. 115-S. McCain National Defense Authorization Act for Fiscal Year 2019 (FY2019 NDAA, P.L. 115-
232) accelerated the development of hypersonic weapons, which USD(R&E) identifies as a 232) accelerated the development of hypersonic weapons, which USD(R&E) identifies as a
priority research and development area, the United States is unlikely to field an operational priority research and development area, the United States is unlikely to field an operational
system before 2023. However, most U.S. hypersonic weapons programs, in contrast to those in system before 2023. However, most U.S. hypersonic weapons programs, in contrast to those in
Russia and China, are not being designed for use with a nuclear warhead.3 As a result, U.S. Russia and China, are not being designed for use with a nuclear warhead.3 As a result, U.S.
hypersonic weapons will likely require greater accuracy and will be more technically challenging hypersonic weapons will likely require greater accuracy and will be more technically challenging
to develop than nuclear-armed Chinese and Russian systems. to develop than nuclear-armed Chinese and Russian systems.
In addition to accelerating development of hypersonic weapons, Section 247 of the FY2019 In addition to accelerating development of hypersonic weapons, Section 247 of the FY2019
NDAA required that the Secretary of Defense, in coordination with the Director of the Defense NDAA required that the Secretary of Defense, in coordination with the Director of the Defense
Intelligence Agency, produce a classified assessment of U.S. and adversary hypersonic weapons Intelligence Agency, produce a classified assessment of U.S. and adversary hypersonic weapons
programs, to include the following elements: programs, to include the following elements:
(1) An evaluation of spending by the United States and adversaries on such technology. (1) An evaluation of spending by the United States and adversaries on such technology.
(2) An evaluation of the quantity and quality of research on such technology. (2) An evaluation of the quantity and quality of research on such technology.
(3) An evaluation of the test infrastructure and workforce supporting such technology. (3) An evaluation of the test infrastructure and workforce supporting such technology.
(4) An assessment of the technological progress of the United States and adversaries on (4) An assessment of the technological progress of the United States and adversaries on
such technology. such technology.
(5) Descriptions of timelines for operational deployment of such technology. (5) Descriptions of timelines for operational deployment of such technology.

1 For details, see CRS Report R41464, 1 For details, see CRS Report R41464, Conventional Prompt Global Strike and Long-Range Ballistic Missiles:
Background and Issues, by Amy F. Woolf. , by Amy F. Woolf.
2 U.S. Congress, Senate Committee on Armed Services, “Testimony of Michael Griffin,” Hearing on New 2 U.S. Congress, Senate Committee on Armed Services, “Testimony of Michael Griffin,” Hearing on New
Technologies to Meet Emerging Threats, April 18, 2018, at https://www.armed-services.senate.gov/imo/media/doc/18-Technologies to Meet Emerging Threats, April 18, 2018, at https://www.armed-services.senate.gov/imo/media/doc/18-
40_04-18-18.pdf. 40_04-18-18.pdf.
3 Until recently, the United States was not believed to be considering the development of nuclear-armed hypersonic 3 Until recently, the United States was not believed to be considering the development of nuclear-armed hypersonic
weapons; however, a since-revoked Air Force solicitation sought ideas for a “thermal protection system that can weapons; however, a since-revoked Air Force solicitation sought ideas for a “thermal protection system that can
support [a] hypersonic glide to ICBM ranges.” Senior defense officials responded to news reports of the revocation, support [a] hypersonic glide to ICBM ranges.” Senior defense officials responded to news reports of the revocation,
stating that DOD “remains committed to non-nuclear role for hypersonics.” See Steve Trimble, “USAF Errantly stating that DOD “remains committed to non-nuclear role for hypersonics.” See Steve Trimble, “USAF Errantly
Reveals Research on ICBM-Range Hypersonic Glide Vehicle,” Aviation Week, August 18, 2020, at Reveals Research on ICBM-Range Hypersonic Glide Vehicle,” Aviation Week, August 18, 2020, at
https://aviationweek.com/defense-space/missile-defense-weapons/usaf-errantly-reveals-research-icbm-range-https://aviationweek.com/defense-space/missile-defense-weapons/usaf-errantly-reveals-research-icbm-range-
hypersonic-glide. hypersonic-glide.
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(6) An assessment of the intent or willingness of adversaries to use such technology.4 (6) An assessment of the intent or willingness of adversaries to use such technology.4
This report was delivered to Congress in July 2019. Similarly, Section 1689 of the FY2019 This report was delivered to Congress in July 2019. Similarly, Section 1689 of the FY2019
NDAA requires the Director of the Missile Defense Agency to produce a report on “how NDAA requires the Director of the Missile Defense Agency to produce a report on “how
hypersonic missile defense can be accelerated to meet emerging hypersonic threats.”5 The hypersonic missile defense can be accelerated to meet emerging hypersonic threats.”5 The
findings of these reports could hold implications for congressional authorizations, appropriations, findings of these reports could hold implications for congressional authorizations, appropriations,
and oversight. and oversight.
The following report reviews the hypersonic weapons programs in the United States, Russia, and The following report reviews the hypersonic weapons programs in the United States, Russia, and
China, providing information on the programs and infrastructure in each nation, based on China, providing information on the programs and infrastructure in each nation, based on
unclassified sources. It also provides a brief summary of the state of global hypersonic weapons unclassified sources. It also provides a brief summary of the state of global hypersonic weapons
research development. It concludes with a discussion of the issues that Congress might address as research development. It concludes with a discussion of the issues that Congress might address as
it considers DOD’s funding requests for U.S. hypersonic technology programs. it considers DOD’s funding requests for U.S. hypersonic technology programs.
Background
Several countries are developing hypersonic weapons, which fly at speeds of at least Mach 5 (five Several countries are developing hypersonic weapons, which fly at speeds of at least Mach 5 (five
times the speed of sound).6 There are two primary categories of hypersonic weapons: times the speed of sound).6 There are two primary categories of hypersonic weapons:
  Hypersonic glide vehicles (HGV) are launched from a rocket before gliding to a are launched from a rocket before gliding to a
target.7 target.7
  Hypersonic cruise missiles are powered by high-speed, air-breathing engines, or are powered by high-speed, air-breathing engines, or
“scramjets,” after acquiring their target. “scramjets,” after acquiring their target.
Unlike ballistic missiles, hypersonic weapons do not follow a ballistic trajectory and can Unlike ballistic missiles, hypersonic weapons do not follow a ballistic trajectory and can
maneuver en route to their destination. As former Vice Chairman of the Joint Chiefs of Staff and maneuver en route to their destination. As former Vice Chairman of the Joint Chiefs of Staff and
former Commander of U.S. Strategic Command General John Hyten has stated, hypersonic former Commander of U.S. Strategic Command General John Hyten has stated, hypersonic
weapons could enable “responsive, long-range, strike options against distant, defended, and/or weapons could enable “responsive, long-range, strike options against distant, defended, and/or
time-critical threats [such as road-mobile missiles] when other forces are unavailable, denied time-critical threats [such as road-mobile missiles] when other forces are unavailable, denied
access, or not preferred.”8 Conventional hypersonic weapons use only kinetic energy—energy access, or not preferred.”8 Conventional hypersonic weapons use only kinetic energy—energy
derived from motion—to destroy unhardened targets or, potentially, underground facilities.9 derived from motion—to destroy unhardened targets or, potentially, underground facilities.9
Hypersonic weapons could challenge detection and defense due to their speed, maneuverability, Hypersonic weapons could challenge detection and defense due to their speed, maneuverability,
and low altitude of flight.10 For example, terrestrial-based radar cannot detect hypersonic and low altitude of flight.10 For example, terrestrial-based radar cannot detect hypersonic
weapons until late in the weapon’s flight.11weapons until late in the weapon’s flight.11 Figure 1 depicts the differences in terrestrial-based depicts the differences in terrestrial-based
radar detection timelines for ballistic missiles versus hypersonic glide vehicles. radar detection timelines for ballistic missiles versus hypersonic glide vehicles.

4 P.L. 115-232, Section 2, Division A, Title II, §247. 4 P.L. 115-232, Section 2, Division A, Title II, §247.
5 P.L. 115-232, Section 2, Division A, Title XVI, §1689. 5 P.L. 115-232, Section 2, Division A, Title XVI, §1689.
6 At a minimum, the United States, Russia, China, Australia, India, France, Germany, and Japan are developing 6 At a minimum, the United States, Russia, China, Australia, India, France, Germany, and Japan are developing
hypersonic weapons technology. See Richard H. Speier et al., hypersonic weapons technology. See Richard H. Speier et al., Hypersonic Missile Proliferation: Hindering the Spread
of a New Class of Weapons, RAND Corporation, 2017, at https://www.rand.org/pubs/research_reports/RR2137.html; , RAND Corporation, 2017, at https://www.rand.org/pubs/research_reports/RR2137.html;
and Mike Yeo, “Japan unveils its hypersonic weapons plans,” and Mike Yeo, “Japan unveils its hypersonic weapons plans,” Defense News, March 14, 2020. March 14, 2020.
7 When HGVs are mated with their rocket booster, the resulting weapon system is often referred to as a hypersonic 7 When HGVs are mated with their rocket booster, the resulting weapon system is often referred to as a hypersonic
boost-glide weapon. boost-glide weapon.
8 U.S. Congress, Senate Committee on Armed Services, “Testimony of John E. Hyten,” Hearing on United States 8 U.S. Congress, Senate Committee on Armed Services, “Testimony of John E. Hyten,” Hearing on United States
Strategic Command and United States Northern Command, February 26, 2019, at https://www.armed-Strategic Command and United States Northern Command, February 26, 2019, at https://www.armed-
services.senate.gov/imo/media/doc/Hyten_02-26-19.pdf. services.senate.gov/imo/media/doc/Hyten_02-26-19.pdf.
9 Richard H. Speier et al., 9 Richard H. Speier et al., Hypersonic Missile Proliferation: Hindering the Spread of a New Class of Weapons, p. 13. , p. 13.
10 See Department of Defense, 10 See Department of Defense, 2019 Missile Defense Review, at https://www.defense.gov/Portals/1/Interactive/2018/11-, at https://www.defense.gov/Portals/1/Interactive/2018/11-
2019-Missile-Defense-Review/The%202019%20MDR_Executive%20Summary.pdf. 2019-Missile-Defense-Review/The%202019%20MDR_Executive%20Summary.pdf.
11 Richard H. Speier et al., 11 Richard H. Speier et al., Hypersonic Missile Proliferation: Hindering the Spread of a New Class of Weapons. .
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Figure 1. Terrestrial-Based Detection of Ballistic Missiles vs.
Hypersonic Glide Vehicles

Source: CRS image based on an image in “Gliding missiles that fly faster than Mach 5 are coming,” CRS image based on an image in “Gliding missiles that fly faster than Mach 5 are coming,” The
Economist, April 6, 2019, https://www.economist.com/science-and-technology/2019/04/06/gliding-missiles-that-fly-, April 6, 2019, https://www.economist.com/science-and-technology/2019/04/06/gliding-missiles-that-fly-
faster-than-mach-5-are-coming. faster-than-mach-5-are-coming.
This delayed detection compresses the timeline for decisionmakers assessing their response This delayed detection compresses the timeline for decisionmakers assessing their response
options and for a defensive system to intercept the attacking weapon—potentially permitting only options and for a defensive system to intercept the attacking weapon—potentially permitting only
a single intercept attempt.12 a single intercept attempt.12
Furthermore, U.S. defense officials have stated that both terrestrial- and current space-based Furthermore, U.S. defense officials have stated that both terrestrial- and current space-based
sensor architectures are insufficient to detect and track hypersonic weapons, with former sensor architectures are insufficient to detect and track hypersonic weapons, with former
USD(R&E) Griffin noting that “hypersonic targets are 10 to 20 times dimmer than what the U.S. USD(R&E) Griffin noting that “hypersonic targets are 10 to 20 times dimmer than what the U.S.
normally tracks by satellites in geostationary orbit.”13 Some analysts have suggested that space-normally tracks by satellites in geostationary orbit.”13 Some analysts have suggested that space-
based sensor layers—integrated with tracking and fire-control systems to direct high-performance based sensor layers—integrated with tracking and fire-control systems to direct high-performance
interceptors or directed energy weapons14—could theoretically present viable options for interceptors or directed energy weapons14—could theoretically present viable options for
defending against hypersonic weapons in the future.15 Indeed, the defending against hypersonic weapons in the future.15 Indeed, the 2019 Missile Defense Review
notes that “such sensors take advantage of the large area viewable from space for improved notes that “such sensors take advantage of the large area viewable from space for improved
tracking and potentially targeting of advanced threats, including HGVs and hypersonic cruise tracking and potentially targeting of advanced threats, including HGVs and hypersonic cruise
missiles.”16 missiles.”16

12 Bradley Perrett et al., “U.S. Navy sees Chinese HGV as part of Wider Threat,” 12 Bradley Perrett et al., “U.S. Navy sees Chinese HGV as part of Wider Threat,” Aviation Week, January 27, 2014. , January 27, 2014.
13 David Vergun, “DOD Scaling Up Effort to Develop Hypersonics,” 13 David Vergun, “DOD Scaling Up Effort to Develop Hypersonics,” DoD News, December 13, 2018, at , December 13, 2018, at
https://dod.defense.gov/News/Article/Article/1712954/dod-scaling-up-effort-to-develop-hypersonics/; see also U.S. https://dod.defense.gov/News/Article/Article/1712954/dod-scaling-up-effort-to-develop-hypersonics/; see also U.S.
Congress, Senate Committee on Armed Services, “Testimony of Michael Griffin,” Hearing on New Technologies to Congress, Senate Committee on Armed Services, “Testimony of Michael Griffin,” Hearing on New Technologies to
Meet Emerging Threats, April 18, 2018, at https://www.armed-services.senate.gov/imo/media/doc/18-40_04-18-18.pdf, Meet Emerging Threats, April 18, 2018, at https://www.armed-services.senate.gov/imo/media/doc/18-40_04-18-18.pdf,
and U.S. Congress, Senate Committee on Armed Services, “Testimony of John E. Hyten,” Hearing on United States and U.S. Congress, Senate Committee on Armed Services, “Testimony of John E. Hyten,” Hearing on United States
Strategic Command and United States Northern Command, February 26, 2019, at https://www.armed-Strategic Command and United States Northern Command, February 26, 2019, at https://www.armed-
services.senate.gov/imo/media/doc/Hyten_02-26-19.pdf. services.senate.gov/imo/media/doc/Hyten_02-26-19.pdf.
14 Section 1664 of the FY2022 NDAA (P.L. 117-81) granted the “Director of the Missile Defense Agency the authority 14 Section 1664 of the FY2022 NDAA (P.L. 117-81) granted the “Director of the Missile Defense Agency the authority
to budget for, direct, and manage directed energy programs applicable for ballistic and hypersonic missile defense to budget for, direct, and manage directed energy programs applicable for ballistic and hypersonic missile defense
missions, in coordination with other directed energy efforts of the Department of Defense.” missions, in coordination with other directed energy efforts of the Department of Defense.”
15 U.S. Congress, Senate Committee on Armed Services, “Testimony of Michael Griffin,” Hearing on New 15 U.S. Congress, Senate Committee on Armed Services, “Testimony of Michael Griffin,” Hearing on New
Technologies to Meet Emerging Threats, April 18, 2018, at https://www.armed-services.senate.gov/imo/media/doc/18-Technologies to Meet Emerging Threats, April 18, 2018, at https://www.armed-services.senate.gov/imo/media/doc/18-
40_04-18-18.pdf; and U.S. Congress, Senate Committee on Armed Services, “Testimony of John E. Hyten,” Hearing 40_04-18-18.pdf; and U.S. Congress, Senate Committee on Armed Services, “Testimony of John E. Hyten,” Hearing
on United States Strategic Command and United States Northern Command, February 26, 2019, at https://www.armed-on United States Strategic Command and United States Northern Command, February 26, 2019, at https://www.armed-
services.senate.gov/imo/media/doc/Hyten_02-26-19.pdf. services.senate.gov/imo/media/doc/Hyten_02-26-19.pdf.
16 Department of Defense, 16 Department of Defense, 2019 Missile Defense Review, p. XVI, at https://www.defense.gov/Portals/1/Interactive/, p. XVI, at https://www.defense.gov/Portals/1/Interactive/
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Other analysts have questioned the affordability, technological feasibility, and/or utility of wide- Other analysts have questioned the affordability, technological feasibility, and/or utility of wide-
area hypersonic weapons defense.17 As physicist and nuclear expert James Acton explains, “point-area hypersonic weapons defense.17 As physicist and nuclear expert James Acton explains, “point-
defense systems, and particularly [Terminal High-Altitude Area Defense (THAAD)], could very defense systems, and particularly [Terminal High-Altitude Area Defense (THAAD)], could very
plausibly be adapted to deal with hypersonic missiles. The disadvantage of those systems is that plausibly be adapted to deal with hypersonic missiles. The disadvantage of those systems is that
they can only defend small areas. To defend the whole of the continental United States, you they can only defend small areas. To defend the whole of the continental United States, you
would need an unaffordable number of THAAD batteries.”18 In addition, some analysts have would need an unaffordable number of THAAD batteries.”18 In addition, some analysts have
argued that the United States’ current command and control architecture would be incapable of argued that the United States’ current command and control architecture would be incapable of
“processing data quickly enough to respond to and neutralize an incoming hypersonic threat.”19 “processing data quickly enough to respond to and neutralize an incoming hypersonic threat.”19
(For additional information on hypersonic missile defense, see CRS In Focus IF11623, (For additional information on hypersonic missile defense, see CRS In Focus IF11623,
Hypersonic Missile Defense: Issues for Congress, by Kelley M. Sayler and Stephen M. McCall.) , by Kelley M. Sayler and Stephen M. McCall.)
United States
The Department of Defense (DOD) is currently developing hypersonic weapons under the Navy’s The Department of Defense (DOD) is currently developing hypersonic weapons under the Navy’s
Conventional Prompt Strike program, which is intended to provide the U.S. military with the Conventional Prompt Strike program, which is intended to provide the U.S. military with the
ability to strike hardened or time-sensitive targets with conventional warheads, as well as through ability to strike hardened or time-sensitive targets with conventional warheads, as well as through
several Air Force, Army, and DARPA programs.20 Those who support these development efforts several Air Force, Army, and DARPA programs.20 Those who support these development efforts
argue that hypersonic weapons could enhance deterrence, as well as provide the U.S. military argue that hypersonic weapons could enhance deterrence, as well as provide the U.S. military
with an ability to defeat capabilities such as advanced air and missile defense systems that form with an ability to defeat capabilities such as advanced air and missile defense systems that form
the foundation of U.S. competitors’ anti-access/area denial strategies.21 In recognition of this, the the foundation of U.S. competitors’ anti-access/area denial strategies.21 In recognition of this, the
2018 National Defense Strategy identifies hypersonic weapons as one of the key technologies identifies hypersonic weapons as one of the key technologies
“[ensuring the United States] will be able to fight and win the wars of the future.”22 Similarly, the “[ensuring the United States] will be able to fight and win the wars of the future.”22 Similarly, the
House Armed Services Committee’s bipartisan House Armed Services Committee’s bipartisan Future of Defense Task Force Report notes that notes that
hypersonic weapons could present challenges to the United States in the years to come.23 hypersonic weapons could present challenges to the United States in the years to come.23
Programs
Unlike programs in China and Russia, U.S. hypersonic weapons are to be conventionally armed. Unlike programs in China and Russia, U.S. hypersonic weapons are to be conventionally armed.
As a result, U.S. hypersonic weapons will likely require greater accuracy and will be more As a result, U.S. hypersonic weapons will likely require greater accuracy and will be more

2018/11-2019-Missile-Defense-Review/The%202019%20MDR_Executive%20Summary.pdf. 2018/11-2019-Missile-Defense-Review/The%202019%20MDR_Executive%20Summary.pdf.
17 See James M. Acton, “Hypersonic Weapons Explainer,” Carnegie Endowment for International Peace, April 2, 2018, 17 See James M. Acton, “Hypersonic Weapons Explainer,” Carnegie Endowment for International Peace, April 2, 2018,
at https://carnegieendowment.org/2018/04/02/hypersonic-weapons-explainer-pub-75957; and Margot van Loon, at https://carnegieendowment.org/2018/04/02/hypersonic-weapons-explainer-pub-75957; and Margot van Loon,
“Hypersonic Weapons: A Primer.” “Hypersonic Weapons: A Primer.”
18 Acton, “Hypersonic Weapons Explainer.” 18 Acton, “Hypersonic Weapons Explainer.”
19 Margot van Loon, “Hypersonic Weapons: A Primer” in 19 Margot van Loon, “Hypersonic Weapons: A Primer” in Defense Technology Program Brief: Hypersonic Weapons, ,
American Foreign Policy Council, May 17, 2019. Some analysts have suggested that future command and control American Foreign Policy Council, May 17, 2019. Some analysts have suggested that future command and control
systems may require autonomous functionality to manage the speed and unpredictability of hypersonic weapons. See systems may require autonomous functionality to manage the speed and unpredictability of hypersonic weapons. See
John L. Dolan, Richard K. Gallagher, and David L. Mann, “Hypersonic Weapons Are Literally Unstoppable (As in John L. Dolan, Richard K. Gallagher, and David L. Mann, “Hypersonic Weapons Are Literally Unstoppable (As in
America Can’t Stop Them),” America Can’t Stop Them),” Real Clear Defense, April 23, 2019, at https://www.realcleardefense.com/articles/2019/, April 23, 2019, at https://www.realcleardefense.com/articles/2019/
04/23/hypersonic_weapons__a_threat_to_national_security_114358.html. 04/23/hypersonic_weapons__a_threat_to_national_security_114358.html.
20 For a full history of U.S. hypersonic weapons programs, see CRS Report R41464, 20 For a full history of U.S. hypersonic weapons programs, see CRS Report R41464, Conventional Prompt Global
Strike and Long-Range Ballistic Missiles: Background and Issues, by Amy F. Woolf. , by Amy F. Woolf.
21 Roger Zakheim and Tom Karako, “China’s Hypersonic Missile Advances and U.S. Defense Responses,” Remarks at 21 Roger Zakheim and Tom Karako, “China’s Hypersonic Missile Advances and U.S. Defense Responses,” Remarks at
the Hudson Institute, March 19, 2019. See also Department of Defense Fiscal Year (FY) 2020 Budget Estimates, Army the Hudson Institute, March 19, 2019. See also Department of Defense Fiscal Year (FY) 2020 Budget Estimates, Army
Justification Book of Research, Development, Test and Evaluation, Volume II, Budget Activity 4, p. 580. Justification Book of Research, Development, Test and Evaluation, Volume II, Budget Activity 4, p. 580.
22 Department of Defense, “Summary of the 2018 National Defense Strategy of The United States of America,” p. 3, at 22 Department of Defense, “Summary of the 2018 National Defense Strategy of The United States of America,” p. 3, at
https://dod.defense.gov/Portals/1/Documents/pubs/2018-National-Defense-Strategy-Summary.pdf. https://dod.defense.gov/Portals/1/Documents/pubs/2018-National-Defense-Strategy-Summary.pdf.
23 House Armed Services Committee, 23 House Armed Services Committee, Future of Defense Task Force Report 2020, September 2020, at , September 2020, at
https://armedservices.house.gov/_cache/files/2/6/26129500-d208-47ba-a9f7-https://armedservices.house.gov/_cache/files/2/6/26129500-d208-47ba-a9f7-
25a8f82828b0/424EB2008281A3C79BA8C7EA71890AE9.future-of-defense-task-force-report.pdf. 25a8f82828b0/424EB2008281A3C79BA8C7EA71890AE9.future-of-defense-task-force-report.pdf.
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link to page link to page 1213 Hypersonic Weapons: Background and Issues for Congress

technically challenging to develop than nuclear-armed Chinese and Russian systems. Indeed, technically challenging to develop than nuclear-armed Chinese and Russian systems. Indeed,
according to one expert, “a nuclear-armed glider would be effective if it were 10 or even 100 according to one expert, “a nuclear-armed glider would be effective if it were 10 or even 100
times less accurate [than a conventionally-armed glider]” due to nuclear blast effects.24 times less accurate [than a conventionally-armed glider]” due to nuclear blast effects.24
According to open-source reporting, the United States is conducting research, development, test, According to open-source reporting, the United States is conducting research, development, test,
and evaluation (RDT&E) on a number of offensive hypersonic weapons and hypersonic and evaluation (RDT&E) on a number of offensive hypersonic weapons and hypersonic
technology programs, including the following (seetechnology programs, including the following (see Table 1): :
 U.S. Navy—Conventional Prompt Strike (CPS);  U.S. Navy—Conventional Prompt Strike (CPS);
 U.S.  U.S. Navy—Offensive Anti-Surface Warfare Increment 2 (OASuW Inc 2), also known as Hypersonic Air-Launched OASuW (HALO);  U.S. Army—Long-Range Hypersonic Weapon (LRHW); Army—Long-Range Hypersonic Weapon (LRHW);
 U.S. Air Force—AGM-183 Air-Launched Rapid Response Weapon (ARRW,  U.S. Air Force—AGM-183 Air-Launched Rapid Response Weapon (ARRW,
pronounced “arrow”); pronounced “arrow”);
 U.S. Air Force—Hypersonic Attack Cruise Missile (HACM);  U.S. Air Force—Hypersonic Attack Cruise Missile (HACM);
 DARPA—Tactical Boost Glide (TBG);  DARPA—Tactical Boost Glide (TBG);
 DARPA—Operational Fires (OpFires); and  DARPA—Operational Fires (OpFires); and
 DARPA—Hypersonic Air-breathing Weapon Concept (HAWC, pronounced  DARPA—Hypersonic Air-breathing Weapon Concept (HAWC, pronounced
“hawk”). “hawk”).
These programs are intended to produce operational prototypes, as there are currently no These programs are intended to produce operational prototypes, as there are currently no
programs of record for hypersonic weapons.25 programs of record for hypersonic weapons.25
U.S. Navy
In a June 2018 memorandum, DOD announced that the Navy would lead the development of a In a June 2018 memorandum, DOD announced that the Navy would lead the development of a
common glide vehicle for use across the services.26 The common glide vehicle is being adapted common glide vehicle for use across the services.26 The common glide vehicle is being adapted
from a Mach 6 Army prototype warhead, the Alternate Re-Entry System, which was successfully from a Mach 6 Army prototype warhead, the Alternate Re-Entry System, which was successfully
tested in 2011 and 2017.27 Once development is complete, “Sandia National Laboratories, the tested in 2011 and 2017.27 Once development is complete, “Sandia National Laboratories, the
designer of the original concept, then will build the common glide vehicles. ... Booster systems designer of the original concept, then will build the common glide vehicles. ... Booster systems
are being developed separately.”28 are being developed separately.”28
The Navy’s Conventional Prompt Strike (CPS) is expected to pair the common glide vehicle with The Navy’s Conventional Prompt Strike (CPS) is expected to pair the common glide vehicle with
a booster system to create a common All Up Round (AUR) for use by both the Navy and Army. a booster system to create a common All Up Round (AUR) for use by both the Navy and Army.
According to the Navy’s According to the Navy’s ~~FY2022~~FY2023 budget documents, the Navy intends to conduct testing in budget documents, the Navy intends to conduct testing in
~~support of CPS’s deployment on Zumwalt-class destroyers by FY2025 and Virginia-class~~
~~submarines by FY2028.29 Although Navy officials have previously noted plans to achieve~~

24 James M. Acton, “China’s Advanced Weapons,” Testimony to the U.S. China Economic and Security Review 24 James M. Acton, “China’s Advanced Weapons,” Testimony to the U.S. China Economic and Security Review
Commission, February 23, 2017, at https://carnegieendowment.org/2017/02/23/china-s-advanced-weapons-pub-68095. Commission, February 23, 2017, at https://carnegieendowment.org/2017/02/23/china-s-advanced-weapons-pub-68095.
25 Steve Trimble, “New Long-Term Pentagon Plan Boosts Hypersonics, But Only Prototypes,” 25 Steve Trimble, “New Long-Term Pentagon Plan Boosts Hypersonics, But Only Prototypes,” Aviation Week, March , March
15, 2019, at https://aviationweek.com/defense/new-long-term-pentagon-plan-boosts-hypersonics-only-prototypes. 15, 2019, at https://aviationweek.com/defense/new-long-term-pentagon-plan-boosts-hypersonics-only-prototypes.
26 The services coordinate efforts on a Common Hypersonic Glide Body Board of Directors with rotating chairmanship. 26 The services coordinate efforts on a Common Hypersonic Glide Body Board of Directors with rotating chairmanship.
Sydney J. FreedbergSydney J. Freedberg, Jr., “Army Ramps up Funding for Laser Shield, Hypersonic Sword,” Jr., “Army Ramps up Funding for Laser Shield, Hypersonic Sword,” Breaking Defense, February , February
28, 2020, at https://breakingdefense.com/2020/02/army-ramps-up-funding-for-laser-shield-hypersonic-sword/. 28, 2020, at https://breakingdefense.com/2020/02/army-ramps-up-funding-for-laser-shield-hypersonic-sword/.
27 Steve Trimble and Guy Norris, “Sandia’s Swerve Could Lead to First-gen Hypersonic Production Line,” 27 Steve Trimble and Guy Norris, “Sandia’s Swerve Could Lead to First-gen Hypersonic Production Line,” Aviation
Week, October 11, 2018, at http://aviationweek.com/air-dominance/sandia-s-swerve-could-lead-first-gen-hypersonic-, October 11, 2018, at http://aviationweek.com/air-dominance/sandia-s-swerve-could-lead-first-gen-hypersonic-
production-line; and Sydney J. Freedberg Jr., “Army Warhead Is Key To Joint Hypersonics,” production-line; and Sydney J. Freedberg Jr., “Army Warhead Is Key To Joint Hypersonics,” Breaking Defense, ,
August 22, 2018, at https://breakingdefense.com/2018/08/army-warhead-is-key-to-joint-hypersonics/. August 22, 2018, at https://breakingdefense.com/2018/08/army-warhead-is-key-to-joint-hypersonics/.
28 Steve Trimble and Guy Norris, “Sandia’s Swerve Could Lead to First-gen Hypersonic Production Line,” 28 Steve Trimble and Guy Norris, “Sandia’s Swerve Could Lead to First-gen Hypersonic Production Line,” Aviation
Week, October 11, 2018, at http://aviationweek.com/air-dominance/sandia-s-swerve-could-lead-first-gen-hypersonic-, October 11, 2018, at http://aviationweek.com/air-dominance/sandia-s-swerve-could-lead-first-gen-hypersonic-
production-line. production-line.
~~29 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Navy Justification Book of Research,~~
Congressional Research Service Congressional Research Service

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Hypersonic Weapons: Background and Issues for Congress

support of CPS’s deployment on Zumwalt-class destroyers by FY2025.29 Although Navy officials have previously noted plans to achieve “limited operating capability” on Ohio-class submarines as early as 202530 and “limited operating capability” on Ohio-class submarines as early as 202530 and on Virginia-class submarines by FY2028, as well as to eventually field to eventually field
hypersonic weapons on Burke-class destroyers, such plans are not reflected in hypersonic weapons on Burke-class destroyers, such plans are not reflected in ~~FY2022~~FY2023 budget budget
documents.31 The Navy is requesting $1.documents.31 The Navy is requesting $1.42 billion for CPS RDT&E in billion for CPS RDT&E in ~~FY2022—an increase of~~
~~$366 million over the FY2021 request and $607 million over the FY2021 appropriation.32~~
~~U.S. Army~~
~~The Army’s Long-Range Hypersonic Weapon~~ FY2023—a decrease of $169 million from the FY2022 request and $120 million from the FY2022 appropriation.32 The Navy is also developing the Offensive Anti-Surface Warfare Increment 2 (OASuW Inc 2), also known as Hypersonic Air-Launched OASuW (HALO)—a new start in FY2023.33 Although few details about the program have been released publicly, HALO is likely to be compatible with the Navy’s F/A-18 fighter jet.34 The Navy is requesting $92 million for HALO RDT&E in FY2023.35 U.S. Army The Army’s Long-Range Hypersonic Weapon (LRHW) program is expected to pair the common glide program is expected to pair the common glide
vehicle with the Navy’s booster system. The system is intended to have a range of over 1,725 vehicle with the Navy’s booster system. The system is intended to have a range of over 1,725
miles and “provide the Army with a prototype strategic attack weapon system to defeat A2/AD miles and “provide the Army with a prototype strategic attack weapon system to defeat A2/AD
capabilities, suppress adversary Long Range Fires, and engage other high payoff/time sensitive capabilities, suppress adversary Long Range Fires, and engage other high payoff/time sensitive
targets.”targets.”3336 The Army is requesting $ The Army is requesting $~~301~~806 million in RDT&E for the program in million in RDT&E for the program in ~~FY2022—$500~~
FY2023—$394 million million ~~under the FY2021~~over the FY2022 request and $ request and $~~531~~380 million million ~~under the FY2021 appropriation.34 It plans to~~
~~conduct flight tests for LRHW in FY2022 and FY2023, field an experimental prototype in~~
~~FY2023, and transition to a program of record in the fourth quarter of FY2024.35~~
~~U.S. Air Force~~
~~The AGM-183 Air-Launched Rapid Response Weapon is expected to leverage DARPA’s Tactical~~
~~Boost Glide technology to develop an air-launched hypersonic glide vehicle prototype capable of~~
~~travelling at average speeds of between Mach 6.5 and Mach 8 at a range of approximately 1,000~~
~~miles.36 Although ARRW successfully completed a “captive carry” test flight in June 2019, it has~~

over the FY2022 29 Department of Defense Fiscal Year (FY) 2023 Budget Estimates, Navy Justification Book of Research, Development, Test and Evaluation, Volume II, Budget Activity 4, p. 1458, at https://www.secnav.navy.mil/fmc/fmb/Documents/23pres/RDTEN_BA4_Book.pdf. 30 See Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Navy Justification Book of Research, Development, Test and Evaluation, Volume II, Budget Activity 4, p. 1466, at Development, Test and Evaluation, Volume II, Budget Activity 4, p. 1466, at
https://www.secnav.navy.mil/fmc/fmb/Documents/22pres/RDTEN_BA4_Book.pdfhttps://www.secnav.navy.mil/fmc/fmb/Documents/22pres/RDTEN_BA4_Book.pdf.
30; Department of the Navy, “Highlights of the Department of the Navy FY 2021 Budget,” February 10, 2020, at Department of the Navy, “Highlights of the Department of the Navy FY 2021 Budget,” February 10, 2020, at
https://www.secnav.navy.mil/fmc/fmb/Documents/21pres/Highlights_book.pdf; and Megan Eckstein, “Navy Says https://www.secnav.navy.mil/fmc/fmb/Documents/21pres/Highlights_book.pdf; and Megan Eckstein, “Navy Says
Hypersonic Weapons Coming to Subs in 5 Years,” Hypersonic Weapons Coming to Subs in 5 Years,” USNI News, November 17, 2020, at https://news.usni.org/2020/11/, November 17, 2020, at https://news.usni.org/2020/11/
17/navy-says-hypersonic-weapons-coming-to-subs-in-5-years. 17/navy-says-hypersonic-weapons-coming-to-subs-in-5-years.
31 David B. Larter, “All US Navy destroyers will get hypersonic missiles, says Trump’s national security adviser,” 31 David B. Larter, “All US Navy destroyers will get hypersonic missiles, says Trump’s national security adviser,”
Defense News, October 21, 2020, at https://www.defensenews.com/naval/2020/10/21/all-us-navy-destroyers-will-get-, October 21, 2020, at https://www.defensenews.com/naval/2020/10/21/all-us-navy-destroyers-will-get-
hypersonic-missiles-trumps-national-security-advisor-says/. hypersonic-missiles-trumps-national-security-advisor-says/.
32 Department of Defense Fiscal Year (FY) 32 Department of Defense Fiscal Year (FY) ~~2022~~2023 Budget Estimates, Navy Justification Book of Research, Development, Test and Evaluation, Volume II, Budget Activity 4, p. 1458, at https://www.secnav.navy.mil/fmc/fmb/Documents/23pres/RDTEN_BA4_Book.pdf. 33 Department of Defense Fiscal Year (FY) 2023 Budget Estimates, Navy Justification Book of Research, Development, Test and Evaluation, Volume II, Budget Activity 4, p. 1373, at https://www.secnav.navy.mil/fmc/fmb/Documents/23pres/RDTEN_BA4_Book.pdf. 34 Joesph Trevithick, “Hypersonic Anti-Ship Cruise Missile Has To Be Ready By 2028 Navy Says,” The Drive, April 23, 2022, at https://www.thedrive.com/the-war-zone/hypersonic-anti-ship-cruise-missile-has-to-be-ready-by-2028-navy-says. 35 Department of Defense Fiscal Year (FY) 2023 Budget Estimates, Navy Justification Book of Research, Budget Estimates, Navy Justification Book of Research,
Development, Test and Evaluation, Volume II, Budget Activity 4, p. Development, Test and Evaluation, Volume II, Budget Activity 4, p. ~~1466~~1373, at , at
https://www.secnav.navy.mil/fmc/fmb/Documents/https://www.secnav.navy.mil/fmc/fmb/Documents/~~22pres~~23pres/RDTEN_BA4_Book.pdf. /RDTEN_BA4_Book.pdf.
3336 Sydney J. Freedberg Jr., “Army Discloses Hypersonic LRHW Range Of 1,725 Miles; Watch Out China,” Breaking Sydney J. Freedberg Jr., “Army Discloses Hypersonic LRHW Range Of 1,725 Miles; Watch Out China,” Breaking
Defense, May, 12 2021, at https://breakingdefense.com/2021/05/army-discloses-hypersonic-lrhw-range-of-1725-miles-Defense, May, 12 2021, at https://breakingdefense.com/2021/05/army-discloses-hypersonic-lrhw-range-of-1725-miles-
watch-out-china/; and at https://breakingdefense.com/2019/03/army-sets-2023-hypersonic-flight-test-strategic-cannon-watch-out-china/; and at https://breakingdefense.com/2019/03/army-sets-2023-hypersonic-flight-test-strategic-cannon-
advances/ Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Army Justification Book of Research, advances/ Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Army Justification Book of Research,
Development, Test and Evaluation, Volume II, Budget Activity 4, p. 639, at Development, Test and Evaluation, Volume II, Budget Activity 4, p. 639, at
https://www.asafm.army.mil/Portals/72/Documents/BudgetMaterial/2022/Base%20Budget/rdte/https://www.asafm.army.mil/Portals/72/Documents/BudgetMaterial/2022/Base%20Budget/rdte/~~RDTE_BA_4_FY_202~~
~~2_PB.pdf.~~
~~34 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Army Justification Book of Research,~~
~~Development, Test and Evaluation, Volume II, Budget Activity 4, p. 639, at~~
~~https://www.asafm.army.mil/Portals/72/Documents/BudgetMaterial/2022/Base%20Budget/rdte/RDTE_BA_4_FY_202~~
~~2_PB.pdf.~~
~~35 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Army Justification Book of Research,~~
~~Development, Test and Evaluation, Volume II, Budget Activity 4, at~~
RDTE_BA_4_FY_2022_PB.pdf. Congressional Research Service 6 Hypersonic Weapons: Background and Issues for Congress appropriation.37 It plans to conduct flight tests for LRHW in FY2022, field an experimental prototype in FY2023, and transition to a program of record in the fourth quarter of FY2024.38 The Army additionally requested $249 million for the procurement of LRHW ground support equipment in FY2023.39 U.S. Air Force The AGM-183 Air-Launched Rapid Response Weapon is expected to leverage DARPA’s Tactical Boost Glide technology to develop an air-launched hypersonic glide vehicle prototype capable of travelling at average speeds of between Mach 6.5 and Mach 8 at a range of approximately 1,000 miles.40 Although ARRW successfully completed a “captive carry” test flight in June 2019, it has experienced failures in all three of its subsequent flight tests.41 The Air Force continues to assert that, despite these failures, “it is still possible to provide [early operational capability] in late calendar year 2022, provided future flight testing [of ARRW] concludes as per the current plan.”42 This schedule could leave little to no room for test delays or additional flight failures. The Air Force has requested $115 million for ARRW RDT&E in FY2023—$123 million under the FY2022 request and $204 million under the FY2022 appropriation.43 In addition, the Air Force 37 Department of Defense Fiscal Year (FY) 2023 Budget Estimates, Army Justification Book of Research, Development, Test and Evaluation, Volume II, Budget Activity 4, pp. 711-726, at https://www.asafm.army.mil/Portals/72/Documents/BudgetMaterial/2023/Base%20Budget/rdte/vol_2-Budget_Activity_4.pdf; and Department of Defense Fiscal Year (FY) 2023 Budget Estimates, Army Justification Book of Research, Development, Test and Evaluation, Volume II, Budget Activity 5D, p. 185, at https://www.asafm.army.mil/Portals/72/Documents/BudgetMaterial/2023/Base%20Budget/rdte/vol_2- Budget_Activity_5D.pdfhttps://www.asafm.army.mil/Portals/72/Documents/BudgetMaterial/2022/Base Budget/rdte/RDTE_BA_4_FY_2022_PB.pdf. 38 Department of Defense Fiscal Year (FY) 2023 Budget Estimates, Army Justification Book of Research, Development, Test and Evaluation, Volume II, Budget Activity 4, pp. 705-709, at https://www.asafm.army.mil/Portals/72/Documents/BudgetMaterial/https://www.asafm.army.mil/Portals/72/Documents/BudgetMaterial/~~2022~~2023/Base%20Budget/rdte//Base%20Budget/rdte/~~RDTE_BA_4_FY_202~~
~~2_PB.pdf.~~
36vol_2-Budget_Activity_4.pdf. 39 Department of Defense Fiscal Year (FY) 2023 Budget Estimates, Army Justification Book of Missile Procurement, p. 66, at https://www.asafm.army.mil/Portals/72/Documents/BudgetMaterial/2023/Base%20Budget/Procurement/MSLS_ARMY.pdf. 40 ARRW is expected to be launched initially from the B-52H strategic bomber. Thomas Newdick, “Air Force Says ARRW is expected to be launched initially from the B-52H strategic bomber. Thomas Newdick, “Air Force Says
New Hypersonic Missile Will Hit Targets 1,000 Miles Away In Under 12 Minutes,” New Hypersonic Missile Will Hit Targets 1,000 Miles Away In Under 12 Minutes,” The Drive, October 13, 2020, at , October 13, 2020, at
https://www.thedrive.com/the-war-zone/37045/air-force-says-new-hypersonic-missile-will-hit-targets-1000-miles-https://www.thedrive.com/the-war-zone/37045/air-force-says-new-hypersonic-missile-will-hit-targets-1000-miles-
~~Congressional Research Service~~

6

~~Hypersonic Weapons: Background and Issues for Congress~~

~~experienced failures in all three of its subsequent flight tests.37 The Air Force continues to assert~~
~~that, despite these failures, “it is still possible to provide [early operational capability] in late~~
~~calendar year 2022, provided future flight testing [of ARRW] concludes as per the current plan.”38~~
~~This schedule could leave little to no room for test delays or additional flight failures. The Air~~
~~Force has requested $238 million for ARRW RDT&E in FY2022—$144 million under the~~
~~FY2021 request and $148 million under the FY2021 appropriation.39 In addition, the Air Force~~
~~requested $161 million in FY2022 for the procurement of an estimated 12 ARRW missiles;40~~
~~Congress authorized $116 million for ARRW procurement in the FY2022 NDAA (P.L. 117-81),~~
~~noting that the additional funds were “early to need.”~~
away-in-under-12-minutes. 41 Oriana Pawlyk, “Air Force’s Hypersonic ARRW Missile Fails First Flight Test,” Military.com, April 6, 2021, at https://www.military.com/daily-news/2021/04/06/air-forces-hypersonic-arrw-missile-fails-first-flight-test.html#:~:text=In%20June%202019%2C%20the%20service,early%202020s%2C%20the%20release%20states; and Anthony Capaccio, “Hypersonic-Missile Failures Risk U.S. Chase of China, Russia,” Bloomberg, March 7, 2022, at https://www.bloomberg.com/news/articles/2022-03-07/hypersonic-missile-failures-imperil-u-s-chase-of-china-russia. 42 Anthony Capaccio, “Hypersonic-Missile Failures Risk U.S. Chase of China, Russia,” Bloomberg, March 7, 2022, at https://www.bloomberg.com/news/articles/2022-03-07/hypersonic-missile-failures-imperil-u-s-chase-of-china-russia. 43 Department of Defense Fiscal Year (FY) 2023 Budget Estimates, Air Force Justification Book of Research, Development, Test and Evaluation, Volume II, p. 145, at https://www.saffm.hq.af.mil/Portals/84/documents/FY23/RDTE_/FY23%20Air%20Force%20Research%20Development%20Test%20and%20Evaluation%20Vol%20II.pdf?ver=LK67U_ThMsX7AwahfurKGw%3d%3d. Congressional Research Service 7 Hypersonic Weapons: Background and Issues for Congress requested $47 million for ARRW procurement in FY2023;44 however, Air Force officials have stated that they will submit a reprogramming request to shift these funds to ARRW RDT&E.45 In February 2020, the Air Force announced that it had cancelled its second hypersonic weapon In February 2020, the Air Force announced that it had cancelled its second hypersonic weapon
program, the Hypersonic Conventional Strike Weapon (HCSW), which had been expected to use program, the Hypersonic Conventional Strike Weapon (HCSW), which had been expected to use
the common glide vehicle and booster system, due to budget pressures that forced it to choose the common glide vehicle and booster system, due to budget pressures that forced it to choose
between ARRW and HCSW.between ARRW and HCSW.4146 Then-Air Force acquisition chief Will Roper explained that ARRW Then-Air Force acquisition chief Will Roper explained that ARRW
was selected because it was more advanced and gave the Air Force additional options. “[ARRW] was selected because it was more advanced and gave the Air Force additional options. “[ARRW]
is smaller; we can carry twice as many on the B-52, and it’s possible it could be on the F-15,” he is smaller; we can carry twice as many on the B-52, and it’s possible it could be on the F-15,” he
explained.explained.4247 A senior Air Force official has since noted that a B-52 could potentially carry four A senior Air Force official has since noted that a B-52 could potentially carry four
ARRWs.ARRWs.4348
Finally, in FY2022, the Air Force launched the Hypersonic Attack Cruise Missile (HACM) Finally, in FY2022, the Air Force launched the Hypersonic Attack Cruise Missile (HACM)
program to develop a hypersonic cruise missile that integrates Air Force and DARPA program to develop a hypersonic cruise missile that integrates Air Force and DARPA
technologies. Some reports indicate that HACM is intended to be launched from both bombers technologies. Some reports indicate that HACM is intended to be launched from both bombers
and fighter aircraft,and fighter aircraft,49 with a senior Air Force official noting that a B-52 could potentially carry 20 with a senior Air Force official noting that a B-52 could potentially carry 20
HACMs or more.HACMs or more.4450 According to the Air Force, “the ability to execute HACM development is contingent upon fully funded and successful predecessor capability development efforts.”51 The Air Force requested $317 million for HACM in FY2023, up from $200 million in the FY2022 request and $190 million in the FY2022 appropriation.52 44 Department of Defense Fiscal Year (FY) 2023 Budget Estimates, Air Force Justification Book of Missile Procurement, Volume I, p. 23, at https://www.saffm.hq.af.mil/Portals/84/documents/FY23/PROCUREMENT_/FY23%20Air%20Force%20Missile%20Procurement.pdf?ver=QeRLpOSY7vcLmsKbr3C-Qw%3d%3d. The Air Force requested $161 million in FY2022 for the procurement of an estimated 12 ARRW missiles. Congress authorized $116 million for ARRW procurement in the FY2022 NDAA (P.L. 117-81), noting that additional funds were “early to need.” ~~According to the Air Force, “the ability to execute HACM development is~~

~~away-in-under-12-minutes.~~
~~37 Oriana Pawlyk, “Air Force’s Hypersonic ARRW Missile Fails First Flight Test,” Military.com, April 6, 2021, at~~
~~https://www.military.com/daily-news/2021/04/06/air-forces-hypersonic-arrw-missile-fails-first-flight-test.html#:~:text=~~
~~In%20June%202019%2C%20the%20service,early%202020s%2C%20the%20release%20states; and Anthony~~
~~Capaccio, “Hypersonic-Missile Failures Risk U.S. Chase of China, Russia,” Bloomberg, March 7, 2022, at~~
~~https://www.bloomberg.com/news/articles/2022-03-07/hypersonic-missile-failures-imperil-u-s-chase-of-china-russia.~~
~~38 Anthony Capaccio, “Hypersonic-Missile Failures Risk U.S. Chase of China, Russia,” Bloomberg, March 7, 2022, at~~
~~https://www.bloomberg.com/news/articles/2022-03-07/hypersonic-missile-failures-imperil-u-s-chase-of-china-russia.~~
~~39 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Air Force Justification Book of Research,~~
~~Development, Test and Evaluation, Volume II, p. 139, at~~
~~https://www.saffm.hq.af.mil/Portals/84/documents/FY22/RDTE_/FY22%20DAF%20J-Book%20-%203600%20-~~
~~%20AF%20RDT%20and%20E%20Vol%20II.pdf?ver=KpJJbVq68o32dSvkjuv_Iw%3d%3d.~~
40 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Air Force Justification Book of Missile Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Air Force Justification Book of Missile
Procurement, Volume I, p. 19, at Procurement, Volume I, p. 19, at
https://www.saffm.hq.af.mil/Portals/84/documents/FY22/PROCUREMENT_/FY22%20DAF%20J-Book%20-https://www.saffm.hq.af.mil/Portals/84/documents/FY22/PROCUREMENT_/FY22%20DAF%20J-Book%20-
%203020%20-%20Missile%20Proc.pdf?ver=GIEj1YH2GS-elMys1wLm1A%3d%3d.%203020%20-%20Missile%20Proc.pdf?ver=GIEj1YH2GS-elMys1wLm1A%3d%3d. https://www.saffm.hq.af.mil/Portals/84/documents/FY22/PROCUREMENT_/FY22 DAF J-Book - 3020 - Missile Proc.pdf?ver=GIEj1YH2GS-elMys1wLm1A%3d%3d 45 Valerie Insinna, “Air Force ditches plans to buy first hypersonic ARRW missile in FY23,” Breaking Defense, March 29, 2022, at https://breakingdefense.com/2022/03/air-force-ditches-plans-to-buy-first-hypersonic-arrw-missile-in-fy23/. 46
41 Valerie Insinna, “US Air Force kills one of its hypersonic weapons programs,” Valerie Insinna, “US Air Force kills one of its hypersonic weapons programs,” Defense News, February 10, 2020, at , February 10, 2020, at
https://www.defensenews.com/smr/federal-budget/2020/02/10/the-air-force-just-canceled-one-of-its-hypersonic-https://www.defensenews.com/smr/federal-budget/2020/02/10/the-air-force-just-canceled-one-of-its-hypersonic-
weapons-programs/. weapons-programs/.
4247 John A. Tirpak, “Roper: The ARRW Hypersonic Missile Better Option for USAF,” John A. Tirpak, “Roper: The ARRW Hypersonic Missile Better Option for USAF,” Air Force Magazine, March 2, , March 2,
2020, at https://www.airforcemag.com/arrw-beat-hcsw-because-its-smaller-better-for-usaf/. Tirpak additionally notes 2020, at https://www.airforcemag.com/arrw-beat-hcsw-because-its-smaller-better-for-usaf/. Tirpak additionally notes
that “the F-15 could accelerate the ARRW to Mach 3 before launch, potentially reducing the size of the booster needed that “the F-15 could accelerate the ARRW to Mach 3 before launch, potentially reducing the size of the booster needed
to get the weapon to hypersonic speed.” to get the weapon to hypersonic speed.”
4348 John A. Tirpak, “Air Force Will Try Again to Launch ARRW Hypersonic Missile in July,” John A. Tirpak, “Air Force Will Try Again to Launch ARRW Hypersonic Missile in July,” Air Force Magazine, ,
June 3, 2021, at https://www.airforcemag.com/air-force-july-launch-arrw-hypersonic-missile/. June 3, 2021, at https://www.airforcemag.com/air-force-july-launch-arrw-hypersonic-missile/.
4449 FY2023 Air Force budget documents note that “the HACM program will prioritize integration on the F-15E platform to enable quick entry into flight test.” 50 John A. Tirpak, “Air Force Will Try Again to Launch ARRW Hypersonic Missile in July,” John A. Tirpak, “Air Force Will Try Again to Launch ARRW Hypersonic Missile in July,” Air Force Magazine, ,
June 3, 2021, at https://www.airforcemag.com/air-force-july-launch-arrw-hypersonic-missile/. June 3, 2021, at https://www.airforcemag.com/air-force-july-launch-arrw-hypersonic-missile/.
~~Congressional Research Service~~

7

~~Hypersonic Weapons: Background and Issues for Congress~~

~~contingent upon fully funded and successful predecessor capability development efforts.”45 The~~
~~Air Force requested $200 million for HACM in FY2022.46~~51 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Air Force Justification Book of Research, Development, Test and Evaluation, Volume II, p. 148, at https://www.saffm.hq.af.mil/Portals/84/documents/FY22/RDTE_/FY22%20DAF%20J-Book%20-%203600%20-%20AF%20RDT%20and%20E%20Vol%20II.pdf?ver=KpJJbVq68o32dSvkjuv_Iw%3d%3d. 52 Department of Defense Fiscal Year (FY) 2023 Budget Estimates, Air Force Justification Book of Research, Development, Test and Evaluation, Volume II, p. 145 and 161, at https://www.saffm.hq.af.mil/Portals/84/documents/FY23/RDTE_/ Congressional Research Service 8 Hypersonic Weapons: Background and Issues for Congress
The Air Force is also seeking information from industry on the Expendable Hypersonic Air- The Air Force is also seeking information from industry on the Expendable Hypersonic Air-
Breathing Multi-Mission Demonstrator Program, alternatively known as Project Mayhem. Breathing Multi-Mission Demonstrator Program, alternatively known as Project Mayhem.
According to Principal Director for Hypersonics Mike White, “Project Mayhem is to look at the According to Principal Director for Hypersonics Mike White, “Project Mayhem is to look at the
next step in what the opportunity space allows relative to hypersonic cruise missile systems” and next step in what the opportunity space allows relative to hypersonic cruise missile systems” and
is intended to be capable of flying “significantly longer ranges than what we’re doing today.”is intended to be capable of flying “significantly longer ranges than what we’re doing today.”4753
Mayhem is reported to be larger than ARRW and capable of carrying multiple payloads for Mayhem is reported to be larger than ARRW and capable of carrying multiple payloads for
different mission sets.different mission sets.4854
DARPA
DARPA, in partnership with the Air Force, continues to test Tactical Boost Glide, a wedge-shaped DARPA, in partnership with the Air Force, continues to test Tactical Boost Glide, a wedge-shaped
hypersonic glide vehicle capable of Mach 7+ flight that “aims to develop and demonstrate hypersonic glide vehicle capable of Mach 7+ flight that “aims to develop and demonstrate
technologies to enable future air-launched, tactical-range hypersonic boost glide systems.”technologies to enable future air-launched, tactical-range hypersonic boost glide systems.”4955 TBG TBG
will “also consider traceability, compatibility, and integration with the Navy Vertical Launch will “also consider traceability, compatibility, and integration with the Navy Vertical Launch
System” and is planned to transition to both the Air Force and the Navy. DARPA has requested System” and is planned to transition to both the Air Force and the Navy. DARPA has requested
$$5030 million for TBG in million for TBG in ~~FY2022—$67~~FY2023—$20 million under the million under the ~~FY2021~~FY2022 request and request and ~~$32 million under~~
~~the FY2021~~ appropriation.appropriation.5056
DARPA’s Operational Fires reportedly seeks to leverage TBG technologies to develop a ground- DARPA’s Operational Fires reportedly seeks to leverage TBG technologies to develop a ground-
launched system that will enable “advanced tactical weapons to penetrate modern enemy air launched system that will enable “advanced tactical weapons to penetrate modern enemy air
defenses and rapidly and precisely engage critical time sensitive targets.” DARPA defenses and rapidly and precisely engage critical time sensitive targets.” DARPA ~~has requested~~
requested and received $45 million for OpFires in FY2022, but did not request funds in FY2023, following the program’s completion.57 DARPA has similarly concluded work on the Hypersonic Air-breathing Weapon Concept (HAWC), which, with Air Force support, sought “to develop and demonstrate critical technologies to enable an effective and affordable air-launched hypersonic cruise missile.”58 FY23%20Air%20Force%20Research%20Development%20Test%20and%20Evaluation%20Vol%20II.pdf?ver=LK67U_ThMsX7AwahfurKGw%3d%3d; and~~$45 million for OpFires in FY2022—$5 million over the FY2021 request and $3 million under~~
~~the FY2022 appropriation.51~~

~~45 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Air Force Justification Book of Research,~~
~~Development, Test and Evaluation, Volume II, p. 148, at~~
~~https://www.saffm.hq.af.mil/Portals/84/documents/FY22/RDTE_/FY22%20DAF%20J-Book%20-%203600%20-~~
~~%20AF%20RDT%20and%20E%20Vol%20II.pdf?ver=KpJJbVq68o32dSvkjuv_Iw%3d%3d.~~
46 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Air Force Justification Book of Research, Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Air Force Justification Book of Research,
Development, Test and Evaluation, Volume II, p. 139, at Development, Test and Evaluation, Volume II, p. 139, at
https://www.saffm.hq.af.mil/Portals/84/documents/FY22/RDTE_/FY22%20DAF%20J-Book%20-%https://www.saffm.hq.af.mil/Portals/84/documents/FY22/RDTE_/FY22%20DAF%20J-Book%20-%~~203600~~2303600%20-%20-
%20AF%20RDT%20and%20E%20Vol%20II.pdf?ver=KpJJbVq68o32dSvkjuv_Iw%3d%3d. %20AF%20RDT%20and%20E%20Vol%20II.pdf?ver=KpJJbVq68o32dSvkjuv_Iw%3d%3d.
4753 Mike White, Remarks at the Center for Strategic and International Studies, “Hypersonic Strike and Defense: A Mike White, Remarks at the Center for Strategic and International Studies, “Hypersonic Strike and Defense: A
Conversation with Mike White,” June 10, 2021, at https://www.csis.org/analysis/hypersonic-strike-and-defense-Conversation with Mike White,” June 10, 2021, at https://www.csis.org/analysis/hypersonic-strike-and-defense-
conversation-mike-white. conversation-mike-white.
4854 See, for example, Rachel S. Cohen, “Hypersonic Attack Cruise Missile Becomes High-Priority USAF Project,” Air See, for example, Rachel S. Cohen, “Hypersonic Attack Cruise Missile Becomes High-Priority USAF Project,” Air
Force Magazine, October 13, 2020, at https://www.airforcemag.com/hypersonic-attack-cruise-missile-becomes-Force Magazine, October 13, 2020, at https://www.airforcemag.com/hypersonic-attack-cruise-missile-becomes-
highpriority-usaf-project/. highpriority-usaf-project/.
4955 “Tactical Boost Glide (TBG) Program Information,” DARPA, https://www.darpa.mil/program/tactical-boost-glide; “Tactical Boost Glide (TBG) Program Information,” DARPA, https://www.darpa.mil/program/tactical-boost-glide;
and Guy Norris, “U.S. Air Force Plans Road Map to Operational Hypersonics,” and Guy Norris, “U.S. Air Force Plans Road Map to Operational Hypersonics,” Aviation Week, July 27, 2017, at , July 27, 2017, at
https://aviationweek.com/defense/us-air-force-plans-road-map-operational-hypersonics. https://aviationweek.com/defense/us-air-force-plans-road-map-operational-hypersonics.
5056 Department of Defense Fiscal Year (FY) Department of Defense Fiscal Year (FY) ~~2022~~2023 Budget Estimates, Defense Advanced Research Projects Agency, Budget Estimates, Defense Advanced Research Projects Agency,
Defense-Wide Justification Book 1 of 5, p. Defense-Wide Justification Book 1 of 5, p. ~~158~~171, at , at
https://comptroller.defense.gov/Portals/45/Documents/defbudget/https://comptroller.defense.gov/Portals/45/Documents/defbudget/~~fy2022~~fy2023/budget_justification/pdfs/03_RDT_and_E//budget_justification/pdfs/03_RDT_and_E/RD
~~TE_Vol1_DARPA_MasterJustificationBook_PB_2022.pdf.~~
51 RDTE_Vol1_DARPA_MasterJustificationBook_PB_2023.pdf; and Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Defense Advanced Research Projects Agency, Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Defense Advanced Research Projects Agency,
Defense-Wide Justification Book 1 of 5, p. Defense-Wide Justification Book 1 of 5, p. ~~159~~158, at , at
https://comptroller.defense.gov/Portals/45/Documents/defbudget/fy2022/budget_justification/pdfs/03_RDT_and_E/https://comptroller.defense.gov/Portals/45/Documents/defbudget/fy2022/budget_justification/pdfs/03_RDT_and_E/RD
~~TE_Vol1_DARPA_MasterJustificationBook_PB_2022.pdf.~~
~~Congressional Research Service~~

8

~~Hypersonic Weapons: Background and Issues for Congress~~

~~In the longer term, DARPA, with Air Force support, is continuing work on the~~ RDTE_Vol1_DARPA_MasterJustificationBook_PB_2022.pdf. 57 Department of Defense Fiscal Year (FY) 2023 Budget Estimates, Defense Advanced Research Projects Agency, Defense-Wide Justification Book 1 of 5, p. 172, at https://comptroller.defense.gov/Portals/45/Documents/defbudget/fy2023/budget_justification/pdfs/03_RDT_and_E/RDTE_Vol1_DARPA_MasterJustificationBook_PB_2023.pdf; and Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Defense Advanced Research Projects Agency, Defense-Wide Justification Book 1 of 5, p. 159, at https://comptroller.defense.gov/Portals/45/Documents/defbudget/fy2022/budget_justification/pdfs/03_RDT_and_E/RDTE_Vol1_DARPA_MasterJustificationBook_PB_2022.pdf. 58 “Hypersonic Air-Hypersonic Air-
~~breathing Weapon Concept, which “seeks to develop and demonstrate critical technologies to~~
~~enable an effective and affordable air-launched hypersonic cruise missile.”52~~ breathing Weapon Concept (HAWC) Program Information,” DARPA, at https://www.darpa.mil/ Congressional Research Service 9 Hypersonic Weapons: Background and Issues for Congress DARPA successfully tested HAWC in March 2022, launching the missile from a B-52 bomber.59 Principal Director Principal Director
for Hypersonics Mike White has stated that for Hypersonics Mike White has stated that ~~such a missile~~hypersonic cruise missiles like HAWC would be smaller than would be smaller than ~~DOD’s~~
hypersonic glide vehicles and could therefore launch from a wider range of platforms. Principal hypersonic glide vehicles and could therefore launch from a wider range of platforms. Principal
Director White has additionally noted that HAWC and other hypersonic cruise missiles could Director White has additionally noted that HAWC and other hypersonic cruise missiles could
integrate seekers more easily than hypersonic glide vehicles.integrate seekers more easily than hypersonic glide vehicles.53 60 DARPA requested DARPA requested and received $10 million to $10 million to
develop HAWC in FY2022develop HAWC in FY2022~~—$10 million under the FY2021 request and $21 million under the~~
~~FY2021 appropriation.54~~.61 DARPA requested $60 million for MoHAWC, the successor program to HAWC, in FY2023.62 Like HAWC, MoHAWC seeks to develop technologies for use in future air-launched hypersonic cruise missiles.63
Table 1. Summary of U.S. Hypersonic Weapons RDT&E Funding
~~FY2021~~FY2022 Request
~~FY2021~~FY2022 Enacted
~~PB2022~~PB2023
Title
($ in millions)
($ in millions)
($ in millions)
Schedule
Conventional Conventional
1, 1,~~008~~
~~767~~
~~1,374~~374 1,325 1,205
Platform Platform
Prompt Strike (CPS) Prompt Strike (CPS)
deployment in deployment in
FY2025 and FY2028 FY2025 and FY2028
Hypersonic Air- 0 0 92 Field in FY2028 Launched OASuW (HALO) Long-Range 412 426 806~~Long-Range~~
~~801~~
~~832~~
~~301~~
Prototype Prototype
Hypersonic Hypersonic
deployment in deployment in
Weapon (LRHW) Weapon (LRHW)
FY2023 FY2023
AGM-183 Air- AGM-183 Air-
~~382~~
~~386~~
~~238~~
~~Early operational~~238 319 115 Flight tests through
Launched Rapid Launched Rapid
~~capability in~~FY2023
Response Weapon Response Weapon
~~CY2022~~
(ARRW) (ARRW)
Hypersonic Attack Hypersonic Attack
0
0
~~200~~200 190 462
Complete Complete ~~critical~~test and
Cruise Missile Cruise Missile
~~design review~~development in in
(HACM) (HACM)
~~FY2023~~FY2027
Tactical Boost Glide Tactical Boost Glide
~~117~~
82
50
~~Continue tests in~~
~~(TBG)~~
~~FY2022~~
~~Operational Fires~~
40
48
45
~~Complete critical~~
~~(OpFires)~~
~~design review in~~
~~FY2022~~50 50 30 Complete third test (TBG) flight in FY2023
Hypersonic Air- Hypersonic Air-
20
31
10
~~Complete final~~10 10 60 Begin integration
breathing Weapon breathing Weapon
~~program review in~~and ground testing
Concept (HAWC) Concept (HAWC)/ in FY2023 MoHAWC program/hypersonic-air-breathing-weapon-concept. 59 Oren Liebermann, “US tested hypersonic missile in mid-March but kept it quiet to avoid escalating tensions with Russia,” CNN, April 5, 2022, at https://us.cnn.com/2022/04/04/politics/us-hypersonic-missile-test/index.html. 60
~~FY2022~~
Source: Program information taken from U.S. Navy, Army, Air Force, and DARPA FY2022 Justification Books,
~~available at https://comptrol er.defense.gov/Budget-Materials/. For the Air Force’s update to ARRW’s schedule~~
~~(from FY2022 to CY2022), see Anthony Capaccio, “Hypersonic-Missile Failures Risk U.S. Chase of China,~~
~~Russia,” Bloomberg, March 7, 2022, at https://www.bloomberg.com/news/articles/2022-03-07/hypersonic-missile-~~
~~failures-imperil-u-s-chase-of-china-russia.~~

~~52 “Hypersonic Air-breathing Weapon Concept (HAWC) Program Information,” DARPA, at https://www.darpa.mil/~~
~~program/hypersonic-air-breathing-weapon-concept.~~
53 “Department of Defense Press Briefing on Hypersonics,” March 2, 2020, at https://www.defense.gov/Newsroom/ “Department of Defense Press Briefing on Hypersonics,” March 2, 2020, at https://www.defense.gov/Newsroom/
Transcripts/Transcript/Article/2101062/department-of-defense-press-briefing-on-hypersonics/. Transcripts/Transcript/Article/2101062/department-of-defense-press-briefing-on-hypersonics/.
5461 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Defense Advanced Research Projects Agency, Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Defense Advanced Research Projects Agency,
Defense-Wide Justification Book 1 of 5, p. 161, at Defense-Wide Justification Book 1 of 5, p. 161, at
https://comptroller.defense.gov/Portals/45/Documents/defbudget/fy2022/budget_justification/pdfs/03_RDT_and_E/https://comptroller.defense.gov/Portals/45/Documents/defbudget/fy2022/budget_justification/pdfs/03_RDT_and_E/RD
~~TE_Vol1_DARPA_MasterJustificationBook_PB_2022.pdf.~~
~~Congressional Research Service~~

9RDTE_Vol1_DARPA_MasterJustificationBook_PB_2022.pdf. 62 Department of Defense Fiscal Year (FY) 2023 Budget Estimates, Defense Advanced Research Projects Agency, Defense-Wide Justification Book 1 of 5, p. 173, at https://comptroller.defense.gov/Portals/45/Documents/defbudget/fy2023/budget_justification/pdfs/03_RDT_and_E/RDTE_Vol1_DARPA_MasterJustificationBook_PB_2023.pdf. 63 Ibid. Congressional Research Service 10 Hypersonic Weapons: Background and Issues for Congress Source: Program information taken from U.S. Navy, Army, Air Force, and DARPA FY2022 and FY2023 Justification Books, available at https://comptrol er.defense.gov/Budget-Materials/. Note: MoHAWC, a new start in FY2023, is the successor program to HAWC, which concluded in FY2022. Hypersonic Missile Defenses64

~~Hypersonic Weapons: Background and Issues for Congress~~

~~Hypersonic Missile Defenses55~~
DOD is also investing in counter-hypersonic weapons capabilities, although former USD(R&E) DOD is also investing in counter-hypersonic weapons capabilities, although former USD(R&E)
Michael Griffin has stated that the United States will not have a defensive capability against Michael Griffin has stated that the United States will not have a defensive capability against
hypersonic weapons until the mid-2020s, at the earliest.hypersonic weapons until the mid-2020s, at the earliest.5665 In September 2018, the Missile Defense In September 2018, the Missile Defense
Agency (MDA)—which in 2017 established a Hypersonic Defense Program pursuant to Section Agency (MDA)—which in 2017 established a Hypersonic Defense Program pursuant to Section
1687 of the FY2017 NDAA (P.L. 114-840)—commissioned 21 white papers to explore 1687 of the FY2017 NDAA (P.L. 114-840)—commissioned 21 white papers to explore
hypersonic missile defense options, including interceptor missiles, hypervelocity projectiles, laser hypersonic missile defense options, including interceptor missiles, hypervelocity projectiles, laser
guns, and electronic attack systems.guns, and electronic attack systems.5766 In January 2020, MDA issued a draft request for prototype In January 2020, MDA issued a draft request for prototype
proposals for a Hypersonic Defense Regional Glide Phase Weapons System interceptorproposals for a Hypersonic Defense Regional Glide Phase Weapons System interceptor~~. This~~
~~effort is~~ intended intended to be fielded in the mid-2030s; however, the program was later cancelled in favor of a nearer-term solution, the Glide Phase Intercept (GPI).67 MDA seeks to field a regional, sea-based GPI capability in the mid- to late 2020s.68 In addition, MDA is developing the Hypersonic and Ballistic Tracking Space Sensor (HBTSS)—which it hopes to launch in March 2023—in an effort to improve the agency’s ability to detect and track incoming missiles.69 MDA requested $89.2 million for HBTSS in FY2023; the agency requested $225.5 million for hypersonic defense in FY2023—down from its $247.9 million FY2022 request and $287.8 million FY2022 appropriation.70 Finally~~to “reduce interceptor key technology and integration risks, anchor modeling~~
~~and simulation in areas of large uncertainty, and to increase the interceptor technology readiness~~
~~levels (TRL) to level 5” (validating components in a relevant environment).58 MDA has also~~
~~awarded four companies—Northrop Grumman, Raytheon, Leidos, and L3Harris—with $20~~
~~million contracts to design prototype space-based (low-Earth orbit) sensors by October 31,~~
~~2020.59 Such sensors could theoretically extend the range at which incoming missiles could be~~
~~detected and tracked—a critical requirement for hypersonic missile defense, according to then-~~
~~USD(R&E) Griffin.60 MDA requested $248 million for hypersonic defense in FY2022—up from~~
~~its $207 million FY2021 request and down from the $273 million FY2021 appropriation.61 In~~
~~addition~~, DARPA is working on a program called Glide Breaker, which “will develop critical , DARPA is working on a program called Glide Breaker, which “will develop critical
component technology to support a lightweight vehicle designed for precise component technology to support a lightweight vehicle designed for precise ~~engagement of~~
~~hypersonic threats at very long range.”62 DARPA requested $7 million for Glide Breaker in~~
~~FY2022, matching the $7 million appropriation in FY2021.63~~

5564 For additional information about hypersonic missile defense, see CRS In Focus IF11623, For additional information about hypersonic missile defense, see CRS In Focus IF11623, Hypersonic Missile
Defense: Issues for Congress, by Kelley M. Sayler, Stephen M. McCall, and Quintin A. Reed. , by Kelley M. Sayler, Stephen M. McCall, and Quintin A. Reed.
5665 “Media Availability With Deputy Secretary Shanahan and Under Secretary of Defense Griffin at NDIA Hypersonics “Media Availability With Deputy Secretary Shanahan and Under Secretary of Defense Griffin at NDIA Hypersonics
Senior Executive Series,” U.S. Department of Defense, December 13, 2018, at https://dod.defense.gov/News/Senior Executive Series,” U.S. Department of Defense, December 13, 2018, at https://dod.defense.gov/News/
Transcripts/Transcript-View/Article/1713396/media-availability-with-deputy-secretary-shanahan-and-under-secretary-Transcripts/Transcript-View/Article/1713396/media-availability-with-deputy-secretary-shanahan-and-under-secretary-
of-defens/. of-defens/.
5766 P.L. 114-840, Section 2, Division A, Title XVI, §1687; P.L. 114-840, Section 2, Division A, Title XVI, §1687; ~~and~~ Hudson and Trimble, “Top U.S. Hypersonic Weapon Hudson and Trimble, “Top U.S. Hypersonic Weapon
Program”; Program”; and Steve Trimble, “A Hypersonic Sputnik?,” p. 21. Steve Trimble, “A Hypersonic Sputnik?,” p. 21.
5867 Missile Defense Agency, “Draft Request for Prototype Proposal: Hypersonic Defense Regional Glide Phase Weapon Missile Defense Agency, “Draft Request for Prototype Proposal: Hypersonic Defense Regional Glide Phase Weapon
System,” January 30, 2020, p. 8System,” January 30, 2020, p. 8~~. TRL measures a technology’s level of maturity; TRL 5 requires validation in a~~
~~relevant environment. For information about specific TRLs, see Troy Carter, “The 9 Technology Readiness Levels of~~
~~the DOD,” TechLink, at https://techlinkcenter.org/technology-readiness-level-dod/.~~
~~59 Sandra Erwin, “Missile Defense Agency selects four companies to develop space sensors,” Space News, October 30,~~
~~2019, at https://spacenews.com/missile-defense-agency-selects-four-companies-to-develop-space-sensors/. Experts~~
~~disagree on the cost and technological feasibility of space-based missile defense.~~
~~60 Media Availability With Deputy Secretary Shanahan and Under Secretary of Defense Griffin.”~~
~~61 Department of Defense Fiscal Year (FY) 2022~~; and Steve Trimble, “MDA Unveils GPI In Retooled Counter-Hypersonic Plan,” Aviation Week, February 4, 2021, at https://aviationweek.com/defense-space/missile-defense-weapons/mda-unveils-gpi-retooled-counter-hypersonic-plan. 68 Steve Trimble, “MDA Unveils GPI In Retooled Counter-Hypersonic Plan,” Aviation Week, February 4, 2021, at https://aviationweek.com/defense-space/missile-defense-weapons/mda-unveils-gpi-retooled-counter-hypersonic-plan. 69 Department of Defense Fiscal Year (FY) 2023 Budget Estimates, Missile Defense Agency, Defense-Wide Budget Estimates, Missile Defense Agency, Defense-Wide
Justification Book 2a of 5, p. Justification Book 2a of 5, p. ~~569~~841, at , at
https://comptroller.defense.gov/Portals/45/Documents/defbudget/https://comptroller.defense.gov/Portals/45/Documents/defbudget/~~fy2022/~~fy2023/budget_justification/pdfs/03_RDT_and_E/budget_justification/pdfs/03_RDT_and_E/RD
~~TE_Vol2_MDA_RDTE_PB22_Justification_Book.pdf.~~
~~62 Department of Defense Fiscal Year (FY) 2021 Budget Estimates, Defense Advanced Research Projects~~RDTE_Vol2_MDA_RDTE_PB23_Justification_Book.pdf; and Defense Budget Overview: United States Department of Defense Fiscal Year 2023 Budget Request, Office of the Under Secretary of Defense (Comptroller)/Chief Financial Officer, April 2022, p. 2-15, at https://comptroller.defense.gov/Portals/45/Documents/defbudget/FY2023/FY2023_Budget_Request_Overview_Book.pdf. 70 Department of Defense Fiscal Year (FY) 2023 Budget Estimates, Missile Defense Agency, Agency,
Defense-Wide Justification Book Defense-Wide Justification Book 12a of 5, p. of 5, p. ~~164.~~
63631 and 853, at https://comptroller.defense.gov/Portals/45/Documents/defbudget/fy2023/budget_justification/pdfs/03_RDT_and_E/RDTE_Vol2_MDA_RDTE_PB23_Justification_Book.pdf; and Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Department of Defense Fiscal Year (FY) 2022 Budget Estimates, ~~Defense Advanced Research Projects~~Missile Defense Agency, Agency,
Defense-Wide Justification Book Defense-Wide Justification Book 12a of 5, p. of 5, p. ~~160~~569, at , at
https://comptroller.defense.gov/Portals/45/Documents/defbudget/fy2022/budget_justification/pdfs/https://comptroller.defense.gov/Portals/45/Documents/defbudget/fy2022/budget_justification/pdfs/03_RDT_and_E/RDTE_Vol2_MDA_RDTE_PB22_Justification_Book.pdf. ~~03_RDT_and_E/RD~~
~~TE_Vol1_DARPA_MasterJustificationBook_PB_2022.pdf.~~
Congressional Research Service Congressional Research Service

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~~link to page 28~~ 11 Hypersonic Weapons: Background and Issues for Congress

engagement of hypersonic threats at very long range.”71 DARPA requested $18 million for Glide Breaker in FY2023, up from its $7 million request and appropriation in FY2022.72 Infrastructure
According to a study mandated by the FY2013 National Defense Authorization Act (P.L. 112- According to a study mandated by the FY2013 National Defense Authorization Act (P.L. 112-
239) and conducted by the Institute for Defense Analyses (IDA),239) and conducted by the Institute for Defense Analyses (IDA),6473 the United States had 48 the United States had 48
critical hypersonic test facilities and mobile assets in 2014 needed for the maturation of critical hypersonic test facilities and mobile assets in 2014 needed for the maturation of
hypersonic technologies for defense systems development through 2030.hypersonic technologies for defense systems development through 2030.6574 These specialized These specialized
facilities, which simulate the unique conditions experienced in hypersonic flight (e.g., speed, facilities, which simulate the unique conditions experienced in hypersonic flight (e.g., speed,
pressure, heating),pressure, heating),6675 included 10 DOD hypersonic ground test facilities, 11 DOD open-air ranges, included 10 DOD hypersonic ground test facilities, 11 DOD open-air ranges,
11 DOD mobile assets, 9 NASA facilities, 2 Department of Energy (DOE) facilities, and 5 11 DOD mobile assets, 9 NASA facilities, 2 Department of Energy (DOE) facilities, and 5
industry or academic facilities.industry or academic facilities.6776 In its 2014 evaluation of U.S. hypersonic test and evaluation In its 2014 evaluation of U.S. hypersonic test and evaluation
infrastructure, IDA noted that “no current U.S. facility can provide full-scale, time-dependent, infrastructure, IDA noted that “no current U.S. facility can provide full-scale, time-dependent,
coupled aerodynamic and thermal-loading environments for flight durations necessary to evaluate coupled aerodynamic and thermal-loading environments for flight durations necessary to evaluate
these characteristics above Mach 8.” these characteristics above Mach 8.”
Since the 2014 study report was published, there have been a number of changes in U.S. Since the 2014 study report was published, there have been a number of changes in U.S.
hypersonic test infrastructure. For example, the University of Notre Dame has opened a Mach 6 hypersonic test infrastructure. For example, the University of Notre Dame has opened a Mach 6
hypersonic wind tunnel and at least one hypersonic testing facility has been inactivated. hypersonic wind tunnel and at least one hypersonic testing facility has been inactivated.
Development of Mach 8 and Mach 10 wind tunnels at Purdue University and the University of Development of Mach 8 and Mach 10 wind tunnels at Purdue University and the University of
Notre Dame, respectively, is ongoing.Notre Dame, respectively, is ongoing.6877 In addition, the University of Arizona modified one of its In addition, the University of Arizona modified one of its
wind tunnels to enable Mach 5 testing, while Texas A&M University—in partnership with Army wind tunnels to enable Mach 5 testing, while Texas A&M University—in partnership with Army
Futures Command—is constructing a kilometer-long Mach 10 wind tunnel.Futures Command—is constructing a kilometer-long Mach 10 wind tunnel.6978 (For a partial list of 71 Department of Defense Fiscal Year (FY) 2021 Budget Estimates, Defense Advanced Research Projects Agency, Defense-Wide Justification Book 1 of 5, p. 164. 72 Department of Defense Fiscal Year (FY) 2023 Budget Estimates, Defense Advanced Research Projects Agency, Defense-Wide Justification Book 1 of 5, p. 169, at https://comptroller.defense.gov/Portals/45/Documents/defbudget/fy2023/budget_justification/pdfs/03_RDT_and_E/RDTE_Vol1_DARPA_MasterJustificationBook_PB_2023.pdf; and Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Defense Advanced Research Projects Agency, Defense-Wide Justification Book 1 of 5, p. 160, at https://comptroller.defense.gov/Portals/45/Documents/defbudget/fy2022/budget_justification/pdfs/03_RDT_and_E/RDTE_Vol1_DARPA_MasterJustificationBook_PB_2022.pdf. 73 P.L. 112-239, Section 2, Division A, Title X, §1071. 74 ~~(For a partial list of~~
~~U.S. hypersonic test assets and their capabilities, see the Appendix.) The United States also uses~~
~~the Royal Australian Air Force Woomera Test Range in Australia and the Andøya Rocket Range~~
~~in Norway for flight testing.70 In January 2019, the Navy announced plans to reactivate its Launch~~
~~Test Complex at China Lake, CA to improve air launch and underwater testing capabilities for the~~
~~conventional prompt strike program.71 According to an assessment conducted by the Government~~

~~64 P.L. 112-239, Section 2, Division A, Title X, §1071.~~
65 A more recent report by the Government Accountability Office states that there are “26 DOD, DOE, NASA, and A more recent report by the Government Accountability Office states that there are “26 DOD, DOE, NASA, and
private U.S. wind tunnel facilities capable of supporting hypersonic research.” Government Accountability Office, private U.S. wind tunnel facilities capable of supporting hypersonic research.” Government Accountability Office,
Hypersonic Weapons: DOD Should Clarify Roles and Responsibilities to Ensure Coordination across Development
Efforts, GAO-21-378, March 22, 2021, p. 15, at https://www.gao.gov/products/gao-21-378. , GAO-21-378, March 22, 2021, p. 15, at https://www.gao.gov/products/gao-21-378.
6675 These conditions additionally require the development of specialized materials such as metals and ceramics. These conditions additionally require the development of specialized materials such as metals and ceramics.
6776 This list is taken directly from a 2014 Institute for Defense Analysis report and, therefore, may not be current. See This list is taken directly from a 2014 Institute for Defense Analysis report and, therefore, may not be current. See
(U//FOUO) Paul F. Piscopo et al., (U//FOUO) Paul F. Piscopo et al., (U) Study on the Ability of the U.S. Test and Evaluation Infrastructure to Effectively
and Efficiently Mature Hypersonic Technologies for Defense Systems Development: Summary Analysis and
Assessment, Institute for Defense Analyses, September 2014. Permission to use this material has been granted by the , Institute for Defense Analyses, September 2014. Permission to use this material has been granted by the
Office of Science and Technology Policy. Office of Science and Technology Policy.
6877 Oriana Pawlyk, “Air Force Expanding Hypersonic Technology Testing at Two Indiana Universities,” Military.com, Oriana Pawlyk, “Air Force Expanding Hypersonic Technology Testing at Two Indiana Universities,” Military.com,
April 23, 2019, at https://www.military.com/daily-news/2019/04/23/air-force-expanding-hypersonic-technology-April 23, 2019, at https://www.military.com/daily-news/2019/04/23/air-force-expanding-hypersonic-technology-
testing-two-indiana-universities.html. testing-two-indiana-universities.html.
6978 University of Arizona, “Mach 5 Quiet Ludwieg Tube,” at https://transition.arizona.edu/facilities/qlt5?_ga= University of Arizona, “Mach 5 Quiet Ludwieg Tube,” at https://transition.arizona.edu/facilities/qlt5?_ga=
2.62515882.768526379.1582843192-983632914.1582843192; and Ashley Tressel, “Army to open hypersonic testing 2.62515882.768526379.1582843192-983632914.1582843192; and Ashley Tressel, “Army to open hypersonic testing
facility at Texas A&M,” Inside Defense, October 13, 2019, https://insidedefense.com/daily-news/army-open-facility at Texas A&M,” Inside Defense, October 13, 2019, https://insidedefense.com/daily-news/army-open-
hypersonic-testing-facility-texas-am. Additional universities such as the University of Maryland, the California hypersonic-testing-facility-texas-am. Additional universities such as the University of Maryland, the California
Institute of Technology, the Georgia Institute of Technology, the Air Force Academy, the University of Tennessee, and Institute of Technology, the Georgia Institute of Technology, the Air Force Academy, the University of Tennessee, and
Virginia Polytechnic Institute and State University also maintain experimental hypersonic facilities or conduct Virginia Polytechnic Institute and State University also maintain experimental hypersonic facilities or conduct
~~hypersonic research.~~
70 (U//FOUO) Paul F. Piscopo et al., (U) Study on the Ability of the U.S. Test and Evaluation Infrastructure.
~~71 “Update: US Navy to develop China Lake to support CPS weapon testing,” Jane’s (subscription required), February~~
~~12, 2019, at https://janes.ihs.com/Janes/Display/FG_1644858-JMR.~~
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~~Hypersonic Weapons: Background and Issues for Congress~~

Congressional Research Service 12 link to page 29 Hypersonic Weapons: Background and Issues for Congress U.S. hypersonic test assets and their capabilities, see the Appendix.) The United States also uses the Royal Australian Air Force Woomera Test Range in Australia and the Andøya Rocket Range in Norway for flight testing.79 In January 2019, the Navy announced plans to reactivate its Launch Test Complex at China Lake, CA to improve air launch and underwater testing capabilities for the conventional prompt strike program.80 According to an assessment conducted by the Government Accountability Office, DOD has dedicated approximately $1 billion to hypersonic facility Accountability Office, DOD has dedicated approximately $1 billion to hypersonic facility
modernization from FY2015 to FY2024.modernization from FY2015 to FY2024.7281
In February 2022, DOD’s Office of Inspector General announced that it had concluded its two- In February 2022, DOD’s Office of Inspector General announced that it had concluded its two-
year-long evaluation of current ground test and evaluation facilities to determine if the capability year-long evaluation of current ground test and evaluation facilities to determine if the capability
and capacity would be sufficient to execute DOD’s planned test schedule; however, DOD did not and capacity would be sufficient to execute DOD’s planned test schedule; however, DOD did not
release the evaluation to the public.release the evaluation to the public.7382 Similarly, an annual report by DOD’s Director of Test and Similarly, an annual report by DOD’s Director of Test and
Evaluation evaluated the sufficiency of U.S. hypersonic weapons test infrastructure; this report Evaluation evaluated the sufficiency of U.S. hypersonic weapons test infrastructure; this report
was not released publicly.was not released publicly.74
83 Congress has also continued to express interest in hypersonic weapons infrastructure. Section 222 Congress has also continued to express interest in hypersonic weapons infrastructure. Section 222
of the FY2021 NDAA (P.L. 116-283) requires the Under Secretary of Defense for Research and of the FY2021 NDAA (P.L. 116-283) requires the Under Secretary of Defense for Research and
Engineering, in consultation with the Director of Operational Test and Evaluation, to submit to Engineering, in consultation with the Director of Operational Test and Evaluation, to submit to
the congressional defense committees “an assessment of the sufficiency of the testing capabilities the congressional defense committees “an assessment of the sufficiency of the testing capabilities
and infrastructure used for fielding hypersonic weapons, and a description of any investments in and infrastructure used for fielding hypersonic weapons, and a description of any investments in
testing capabilities and infrastructure that may be required to support in-flight and ground-based testing capabilities and infrastructure that may be required to support in-flight and ground-based
testing for such weapons.” Section 225 of the FY2022 NDAA (P.L. 117-81) requires the Secretary testing for such weapons.” Section 225 of the FY2022 NDAA (P.L. 117-81) requires the Secretary
of Defense to identify the hypersonic facilities and capabilities of the Major Range and Test of Defense to identify the hypersonic facilities and capabilities of the Major Range and Test
Facility Base and brief the congressional defense committees on a plan for improvement. Facility Base and brief the congressional defense committees on a plan for improvement.
Finally, in March 2020, DOD announced that it had established a “hypersonic war room” to Finally, in March 2020, DOD announced that it had established a “hypersonic war room” to
assess the U.S. industrial base for hypersonic weapons and identify “critical nodes” in the supply assess the U.S. industrial base for hypersonic weapons and identify “critical nodes” in the supply
chain.chain.7584 DOD has also amended its “5000 series” acquisition policy in order to enhance supply DOD has also amended its “5000 series” acquisition policy in order to enhance supply
chain resiliency and reduce sustainment costs.chain resiliency and reduce sustainment costs.76
~~Russia~~
~~Although Russia has conducted research on hypersonic weapons technology since the 1980s, it~~
~~accelerated its efforts in response to U.S. missile defense deployments in both the United States~~
~~and Europe, and in response to the U.S. withdrawal from the Anti-Ballistic Missile Treaty in~~
~~2001.77 Detailing Russia’s concerns, President Putin stated that “the US is permitting constant,~~
~~uncontrolled growth of the number of anti-ballistic missiles, improving their quality, and creating~~

7285 hypersonic research. 79 (U//FOUO) Paul F. Piscopo et al., (U) Study on the Ability of the U.S. Test and Evaluation Infrastructure. 80 “Update: US Navy to develop China Lake to support CPS weapon testing,” Jane’s (subscription required), February 12, 2019, at https://janes.ihs.com/Janes/Display/FG_1644858-JMR. 81 Government Accountability Office, Government Accountability Office, Hypersonic Weapons: DOD Should Clarify Roles and Responsibilities to Ensure
Coordination across Development Efforts, GAO-21-378, March 22, 2021, p. 27, at https://www.gao.gov/products/gao-, GAO-21-378, March 22, 2021, p. 27, at https://www.gao.gov/products/gao-
21-378. 21-378.
7382 See Department of Defense Office of Inspector General, “Memorandum for Distribution: Evaluation of the Ground See Department of Defense Office of Inspector General, “Memorandum for Distribution: Evaluation of the Ground
Test and Evaluation Infrastructure Supporting Hypersonic Capabilities (Project No. D2020-DEV0SN-0106.000),” Test and Evaluation Infrastructure Supporting Hypersonic Capabilities (Project No. D2020-DEV0SN-0106.000),”
April 13, 2020, at https://media.defense.gov/2020/Apr/14/2002280826/-1/-1/1/D2020-DEV0SN-0106.000.PDF; and April 13, 2020, at https://media.defense.gov/2020/Apr/14/2002280826/-1/-1/1/D2020-DEV0SN-0106.000.PDF; and
Department of Defense Office of Inspector General,” Evaluation of the Ground Test and Evaluation Infrastructure Department of Defense Office of Inspector General,” Evaluation of the Ground Test and Evaluation Infrastructure
Supporting Hypersonic Capabilities (DODIG-2022-056),” February 3, 2022, at Supporting Hypersonic Capabilities (DODIG-2022-056),” February 3, 2022, at
https://www.dodig.mil/reports.html/Article/2921419/evaluation-of-the-ground-test-and-evaluation-infrastructure-https://www.dodig.mil/reports.html/Article/2921419/evaluation-of-the-ground-test-and-evaluation-infrastructure-
supporting-hyperson/. supporting-hyperson/.
7483 Anthony Capaccio, “Pentagon Hypersonic Weapons Tests Need More Wide-Open Spaces,” Anthony Capaccio, “Pentagon Hypersonic Weapons Tests Need More Wide-Open Spaces,” Bloomberg, February 3, , February 3,
2020. 2020.
7584 Aaron Mehta, “Pentagon launches hypersonic industrial base study,” Aaron Mehta, “Pentagon launches hypersonic industrial base study,” Defense News, March 3, 2020, at , March 3, 2020, at
https://www.defensenews.com/pentagon/2020/03/02/pentagon-launches-hypersonic-industrial-base-study/. https://www.defensenews.com/pentagon/2020/03/02/pentagon-launches-hypersonic-industrial-base-study/.
7685 C. Todd Lopez, “Rewrite of Acquisition Regulation Helps U.S. Build Hypersonic Arsenal More Quickly,” C. Todd Lopez, “Rewrite of Acquisition Regulation Helps U.S. Build Hypersonic Arsenal More Quickly,” DOD
News, October 30, 2020, at https://www.defense.gov/Explore/News/Article/Article/2400205/rewrite-of-acquisition-, October 30, 2020, at https://www.defense.gov/Explore/News/Article/Article/2400205/rewrite-of-acquisition-
regulation-helps-us-build-hypersonic-arsenal-more-quickly/. regulation-helps-us-build-hypersonic-arsenal-more-quickly/.
~~77 United Nations Office of Disarmament Affairs,~~Congressional Research Service 13 link to page 18 Hypersonic Weapons: ~~A Challenge and Opportunity for Strategic~~
~~Arms Control, February 2019, at https://www.un.org/disarmament/publications/more/hypersonic-weapons-a-challenge-~~
~~and-opportunity-for-strategic-arms-control/.~~
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Background and Issues for Congress Russia Although Russia has conducted research on hypersonic weapons technology since the 1980s, it accelerated its efforts in response to U.S. missile defense deployments in both the United States and Europe, and in response to the U.S. withdrawal from the Anti-Ballistic Missile Treaty in 2001.86 Detailing Russia’s concerns, President Putin stated that “the US is permitting constant, uncontrolled growth of the number of anti-ballistic missiles, improving their quality, and creating new missile launching areas. If we do not do something, eventually this will result in the new missile launching areas. If we do not do something, eventually this will result in the
complete devaluation of Russia’s nuclear potential. Meaning that all of our missiles could simply complete devaluation of Russia’s nuclear potential. Meaning that all of our missiles could simply
be intercepted.”be intercepted.”7887 Russia thus seeks hypersonic weapons, which can maneuver as they approach Russia thus seeks hypersonic weapons, which can maneuver as they approach
their targets, as an assured means of penetrating U.S. missile defenses and restoring its sense of their targets, as an assured means of penetrating U.S. missile defenses and restoring its sense of
strategic stability.strategic stability.7988
Programs
Russia is pursuing two hypersonic weapons programs—the Avangard and the 3M22 Tsirkon (or Russia is pursuing two hypersonic weapons programs—the Avangard and the 3M22 Tsirkon (or
Zircon)—and has reportedly fielded the Kinzhal (“Dagger”), a maneuvering air-launched ballistic Zircon)—and has reportedly fielded the Kinzhal (“Dagger”), a maneuvering air-launched ballistic
missile.missile.8089
Avangard Avangard (Figure 2) is a hypersonic glide vehicle launched from an intercontinental ballistic is a hypersonic glide vehicle launched from an intercontinental ballistic
missile (ICBM), giving it “effectively ‘unlimited’ range.”missile (ICBM), giving it “effectively ‘unlimited’ range.”8190 Reports indicate that Avangard is Reports indicate that Avangard is
currently deployed on the SS-19 Stiletto ICBM, though Russia plans to eventually launch the currently deployed on the SS-19 Stiletto ICBM, though Russia plans to eventually launch the
vehicle from the Sarmat ICBM. Sarmat is still in development, although it vehicle from the Sarmat ICBM. Sarmat is still in development, although it was successfully tested in April 2022 and is scheduled to be is scheduled to be
deployed by the end of 2022.deployed by the end of 2022.8291 Avangard features onboard countermeasures and will reportedly Avangard features onboard countermeasures and will reportedly
carry a nuclear warhead. It was successfully tested twice in 2016 and once in December 2018, carry a nuclear warhead. It was successfully tested twice in 2016 and once in December 2018,
reportedly reaching speeds of Mach 20; however, an October 2017 test resulted in failure. reportedly reaching speeds of Mach 20; however, an October 2017 test resulted in failure.
Russian news sources claim that Avangard entered into combat duty in December 2019.Russian news sources claim that Avangard entered into combat duty in December 2019.8392

7886 United Nations Office of Disarmament Affairs, Hypersonic Weapons: A Challenge and Opportunity for Strategic Arms Control, February 2019, at https://www.un.org/disarmament/publications/more/hypersonic-weapons-a-challenge-and-opportunity-for-strategic-arms-control/. 87 Vladimir Putin, “Presidential Address to the Federal Assembly,” March 1, 2018, at http://en.kremlin.ru/events/ Vladimir Putin, “Presidential Address to the Federal Assembly,” March 1, 2018, at http://en.kremlin.ru/events/
president/news/56957. president/news/56957.
7988 In this instance, “strategic stability” refers to a “bilateral nuclear relationship of mutual vulnerability.” See Tong In this instance, “strategic stability” refers to a “bilateral nuclear relationship of mutual vulnerability.” See Tong
Zhao, “Conventional Challenges to Strategic Stability: Chinese Perceptions of Hypersonic Technology and the Security Zhao, “Conventional Challenges to Strategic Stability: Chinese Perceptions of Hypersonic Technology and the Security
Dilemma,” Carnegie-Tsinghua Center for Global Policy, July 23, 2018, at https://carnegietsinghua.org/2018/07/23/Dilemma,” Carnegie-Tsinghua Center for Global Policy, July 23, 2018, at https://carnegietsinghua.org/2018/07/23/
conventional-challenges-to-strategic-stability-chinese-perceptions-of-hypersonic-technology-and-security-dilemma-conventional-challenges-to-strategic-stability-chinese-perceptions-of-hypersonic-technology-and-security-dilemma-
pub-76894. pub-76894.
8089 Although the Kinzhal is a maneuvering air-launched ballistic missile rather than a hypersonic glide vehicle or Although the Kinzhal is a maneuvering air-launched ballistic missile rather than a hypersonic glide vehicle or
hypersonic cruise missile, it is often included in reporting of Russia’s hypersonic weapons program. For this reason—hypersonic cruise missile, it is often included in reporting of Russia’s hypersonic weapons program. For this reason—
and because it poses defensive challenges that are similar to other hypersonic weapons—it is included here for and because it poses defensive challenges that are similar to other hypersonic weapons—it is included here for
reference. reference.
8190 Steve Trimble, “A Hypersonic Sputnik?,” Steve Trimble, “A Hypersonic Sputnik?,” Aviation Week, January 14-27, 2019, p. 20. , January 14-27, 2019, p. 20.
8291 Lateshia Beachum, Mary Ilyushina and Karoun Demirjian, “Russia’s ‘Satan 2’ missile changes little for U.S., scholars say,” Washington Post, April 20, 2022, at https://www.washingtonpost.com/world/2022/04/20/satan-2-icbm/; and Nicholas Fiorenza, “Putin outlines development of Russia’s nuclear triad,” Nicholas Fiorenza, “Putin outlines development of Russia’s nuclear triad,” Jane’s Defence Weekly (subscription (subscription
required), April 22, 2021, at https://customer.janes.com/DefenceWeekly/Display/FG_3953700-JDW. Sarmat could required), April 22, 2021, at https://customer.janes.com/DefenceWeekly/Display/FG_3953700-JDW. Sarmat could
reportedly accommodate at least three Avangard vehicles. See Malcolm Claus, “Russia unveils new strategic delivery reportedly accommodate at least three Avangard vehicles. See Malcolm Claus, “Russia unveils new strategic delivery
systems,” systems,” Jane’s (subscription required), at https://janes.ihs.com/Janes/Display/FG_899127-JIR. (subscription required), at https://janes.ihs.com/Janes/Display/FG_899127-JIR.
83 92 “First regiment of Avangard hypersonic missile systems goes on combat duty in Russia,” “First regiment of Avangard hypersonic missile systems goes on combat duty in Russia,” TASS, December 27, 2019, , December 27, 2019,
at https://tass.com/defense/1104297. at https://tass.com/defense/1104297.
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Figure 2. Artist Rendering of Avangard

Source: https://janes.ihs.com/Janes/Display/FG_899127-JIR. https://janes.ihs.com/Janes/Display/FG_899127-JIR.
In addition to Avangard, Russia is developing Tsirkon, a ship-launched hypersonic cruise missile In addition to Avangard, Russia is developing Tsirkon, a ship-launched hypersonic cruise missile
capable of traveling at speeds of between Mach 6 and Mach 8. Tsirkon is reportedly capable of capable of traveling at speeds of between Mach 6 and Mach 8. Tsirkon is reportedly capable of
striking both ground and naval targets. According to Russian news sources, Tsirkon has a range of striking both ground and naval targets. According to Russian news sources, Tsirkon has a range of
between approximately 250 and 600 miles and can be fired from the vertical launch systems between approximately 250 and 600 miles and can be fired from the vertical launch systems
mounted on cruisers mounted on cruisers Admiral Nakhimov and and Pyotr Veliky, Project 20380 corvettes, Project 22350 , Project 20380 corvettes, Project 22350
frigates, and Project 885 Yasen-class submarines, among other platforms.frigates, and Project 885 Yasen-class submarines, among other platforms.8493 These sources assert These sources assert
that Tsirkon was successfully launched from a Project 22350 frigate in January, October, and that Tsirkon was successfully launched from a Project 22350 frigate in January, October, and
December 2020 and from a Project 885 Yasen-class submarine in October 2021.December 2020 and from a Project 885 Yasen-class submarine in October 2021.8594 U.S. U.S.
intelligence reports indicate that the missile will become operational in 2023.intelligence reports indicate that the missile will become operational in 2023.8695
In addition, Russia has In addition, Russia has ~~reportedly~~ fielded Kinzhal, a maneuvering air-launched ballistic missile fielded Kinzhal, a maneuvering air-launched ballistic missile
modified from the Iskander missile. modified from the Iskander missile. ~~According to U.S. intelligence reports, Kinzhal was~~
~~successfully test fired from a modified MiG-31 fighter (NATO code name: Foxhound) in July~~
~~2018—striking a target at a distance of approximately 500 miles—and may now be ready for~~
~~combat.87 Russia plans to deploy the missile on both the MiG-31 and the Su-34 long-range strike~~
~~fighter.88 Russia is working to mount the missile on the Tu-22M3 strategic bomber (NATO code~~

84Russia reportedly fired Kinzhal from a MiG-31 interceptor aircraft in Ukraine96 and additionally plans to deploy the missile on the Su-34 long-range strike fighter97 and the Tu-22M3 strategic bomber, although the slower-moving bomber may face challenges in “accelerating the weapon into the correct launch parameters.”98 Russian media has reported Kinzhal’s top speed as Mach 10, with a range of up to 1,200 miles when launched from the MiG- 93 “Russia makes over 10 test launches of Tsirkon seaborne hypersonic missile,” “Russia makes over 10 test launches of Tsirkon seaborne hypersonic missile,” TASS, December 21, 2018, at , December 21, 2018, at
http://tass.com/defense/1037426. See also http://tass.com/defense/1037426. See also Russia Military Power: Building a Military to Support Great Power
Aspirations, Defense Intelligence Agency, 2017, p. 79, at https://www.dia.mil/portals/27/documents/news/, Defense Intelligence Agency, 2017, p. 79, at https://www.dia.mil/portals/27/documents/news/
military%20power%20publications/russia%20military%20power%20report%202017.pdf. military%20power%20publications/russia%20military%20power%20report%202017.pdf.
8594 “TASS: Russia Conducts First Ship-Based Hypersonic Missile Test,” “TASS: Russia Conducts First Ship-Based Hypersonic Missile Test,” Reuters, February 27, 2020, at , February 27, 2020, at
https://www.voanews.com/europe/tass-russia-conducts-first-ship-based-hypersonic-missile-test; and Samuel Cranny-https://www.voanews.com/europe/tass-russia-conducts-first-ship-based-hypersonic-missile-test; and Samuel Cranny-
Evans, “Russia conducts first submarine test launches of Tsirkon hypersonic missile,” Evans, “Russia conducts first submarine test launches of Tsirkon hypersonic missile,” Jane’s (subscription required), (subscription required),
October 4, 2021. October 4, 2021.
8695 Amanda Macias, “Russia again successfully tests ship-based hypersonic missile—which will likely be ready for Amanda Macias, “Russia again successfully tests ship-based hypersonic missile—which will likely be ready for
combat by 2022,”combat by 2022,” CNBC, December 20, 2018, at https://www.cnbc.com/2018/12/20/russia-tests-hypersonic-missile-, December 20, 2018, at https://www.cnbc.com/2018/12/20/russia-tests-hypersonic-missile-
that-could-be-ready-for-war-by-2022.html; and “Russian Navy to accept latest Tsirkon hypersonic missile for service that-could-be-ready-for-war-by-2022.html; and “Russian Navy to accept latest Tsirkon hypersonic missile for service
in 2023—source,” in 2023—source,” TASS, March 20, 2019, at http://tass.com/defense/1049572. , March 20, 2019, at http://tass.com/defense/1049572.
~~87 Amanda Macias, “Russia’s new hypersonic missile, which can be launched from warplanes, will likely be ready for~~
~~combat by 2020,” CNBC, July 13, 2018, at https://www.cnbc.com/2018/07/13/russia-new-hypersonic-missile-likely-~~
~~ready-for-war-by-2020.html.~~
8896 Roxana Tiron, “Hypersonic Weapons: Who Has Them and Why It Matters,” Washington Post, April 6, 2022, at https://www.washingtonpost.com/business/hypersonic-weapons-who-has-them-and-why-it-matters/2022/04/05/1f6d0280-b557-11ec-8358-20aa16355fb4_story.html. 97 Mark B. Schneider, “Moscow’s Development of Hypersonic Missiles … and What It Means” in Mark B. Schneider, “Moscow’s Development of Hypersonic Missiles … and What It Means” in Defense Technology
Program Brief: Hypersonic Weapons, American Foreign Policy Council, May 17, 2019. , American Foreign Policy Council, May 17, 2019.
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~~name: Backfire), although the slower-moving bomber may face challenges in “accelerating the~~
~~weapon into the correct launch parameters.”89~~
~~Russian media has reported Kinzhal’s top speed as Mach 10, with a range of up to 1,200 miles~~
~~when launched from the MiG-~~98 Dave Majumdar, “Russia: New Kinzhal Aero-Ballistic Missile Has 3,000 km Range if Fired from Supersonic Bomber,” The National Interest, July 18, 2018, at https://nationalinterest.org/blog/buzz/russia-new-kinzhal-aero-ballistic-missile-has-3000-km-range-if-fired-supersonic-bomber. Congressional Research Service 15 Hypersonic Weapons: Background and Issues for Congress 31. The Kinzhal is reportedly capable of maneuverable flight, as 31. The Kinzhal is reportedly capable of maneuverable flight, as
well as of striking both ground and naval targets, and could eventually be fitted with a nuclear well as of striking both ground and naval targets, and could eventually be fitted with a nuclear
warhead. However, such claims regarding Kinzhal’s performance characteristics have not been warhead. However, such claims regarding Kinzhal’s performance characteristics have not been
publicly verified by U.S. intelligence agencies, and have been met with skepticism by a number publicly verified by U.S. intelligence agencies, and have been met with skepticism by a number
of analysts.of analysts.9099
Infrastructure
Russia reportedly conducts hypersonic wind tunnel testing at the Central Aero-Hydrodynamic Russia reportedly conducts hypersonic wind tunnel testing at the Central Aero-Hydrodynamic
Institute in Zhukovsky and the Khristianovich Institute of Theoretical and Applied Mechanics in Institute in Zhukovsky and the Khristianovich Institute of Theoretical and Applied Mechanics in
Novosibirsk, and has tested hypersonic weapons at Dombarovskiy Air Base, the Baykonur Novosibirsk, and has tested hypersonic weapons at Dombarovskiy Air Base, the Baykonur
Cosmodrome, and the Kura Range.Cosmodrome, and the Kura Range.91100
China
According to Tong Zhao, a fellow at the Carnegie-Tsinghua Center for Global Policy, “most According to Tong Zhao, a fellow at the Carnegie-Tsinghua Center for Global Policy, “most
experts argue that the most important reason to prioritize hypersonic technology development [in experts argue that the most important reason to prioritize hypersonic technology development [in
China] is the necessity to counter specific security threats from increasingly sophisticated U.S. China] is the necessity to counter specific security threats from increasingly sophisticated U.S.
military technology,” such as U.S. missile defenses.military technology,” such as U.S. missile defenses.92101 In particular, China’s pursuit of hypersonic In particular, China’s pursuit of hypersonic
weapons, like Russia’s, reflects a concern that U.S. hypersonic weapons could enable the United weapons, like Russia’s, reflects a concern that U.S. hypersonic weapons could enable the United
States to conduct a preemptive, decapitating strike on China’s nuclear arsenal and supporting States to conduct a preemptive, decapitating strike on China’s nuclear arsenal and supporting
infrastructure. U.S. missile defense deployments could then limit China’s ability to conduct a infrastructure. U.S. missile defense deployments could then limit China’s ability to conduct a
retaliatory strike against the United States.retaliatory strike against the United States.93102
As General Terrence O’Shaughnessy, then-commander of United States Northern Command As General Terrence O’Shaughnessy, then-commander of United States Northern Command
(USNORTHCOM) and North American Aerospace Defense Command (NORAD), testified in a (USNORTHCOM) and North American Aerospace Defense Command (NORAD), testified in a
February 2020 hearing before the Senate Armed Services Committee, China is “testing a February 2020 hearing before the Senate Armed Services Committee, China is “testing a
[nuclear-capable] intercontinental-range hypersonic glide vehicle” that could evade U.S. missile [nuclear-capable] intercontinental-range hypersonic glide vehicle” that could evade U.S. missile
defense and warning systems.defense and warning systems.94103 Reports additionally indicate that China may have tested a Reports additionally indicate that China may have tested a

~~89 Dave Majumdar, “Russia: New Kinzhal Aero-Ballistic Missile Has 3,000 km Range if Fired from Supersonic~~
~~Bomber,” The National Interest, July 18, 2018, at https://nationalinterest.org/blog/buzz/russia-new-kinzhal-aero-~~
~~ballistic-missile-has-3000-km-range-if-fired-supersonic-bomber.~~
90nuclear-capable HGV104—launched by a Long March rocket—in August 2021.105 In contrast to the ballistic missiles that China has previously used to launch HGVs, the Long March, a 99 David Axe, “Is Kinzhal, Russia’s New Hypersonic Missile, a Game Changer?,” David Axe, “Is Kinzhal, Russia’s New Hypersonic Missile, a Game Changer?,” The Daily Beast, March 15, 2018, at , March 15, 2018, at
https://www.thedailybeast.com/is-kinzhal-russias-new-hypersonic-missile-a-game-changer. https://www.thedailybeast.com/is-kinzhal-russias-new-hypersonic-missile-a-game-changer.
91100 “Aerodynamics,” Central Aerohydrodynamic Institute, http://tsagi.com/research/aerodynamics/; “Russia announces “Aerodynamics,” Central Aerohydrodynamic Institute, http://tsagi.com/research/aerodynamics/; “Russia announces
successful flight test of Avangard hypersonic glide vehicle,” successful flight test of Avangard hypersonic glide vehicle,” Jane’s (subscription required), January 3, 2019, at (subscription required), January 3, 2019, at
https://janes.ihs.com/Janes/Display/FG_1451630-JMR; and “Avangard system is tested, said to be fully ready for https://janes.ihs.com/Janes/Display/FG_1451630-JMR; and “Avangard system is tested, said to be fully ready for
deployment,” Russian Strategic Nuclear Forces, December 26, 2018, at http://russianforces.org/blog/2018/12/deployment,” Russian Strategic Nuclear Forces, December 26, 2018, at http://russianforces.org/blog/2018/12/
avangard_system_is_tested_said.shtml. avangard_system_is_tested_said.shtml.
92101 Tong Zhao, “Conventional Challenges to Strategic Stability: Chinese Perceptions of Hypersonic Technology and the Tong Zhao, “Conventional Challenges to Strategic Stability: Chinese Perceptions of Hypersonic Technology and the
Security Dilemma.” Security Dilemma.”
93102 Tong Zhao, “Conventional Challenges to Strategic Stability”; and Lora Saalman, “China’s Calculus on Hypersonic Tong Zhao, “Conventional Challenges to Strategic Stability”; and Lora Saalman, “China’s Calculus on Hypersonic
Glide,” August 15, 2017, Stockholm International Peace Research Institute, at https://www.sipri.org/commentary/Glide,” August 15, 2017, Stockholm International Peace Research Institute, at https://www.sipri.org/commentary/
topical-backgrounder/2017/chinas-calculus-hypersonic-glide. topical-backgrounder/2017/chinas-calculus-hypersonic-glide.
94103 General Terrence J. O’Shaughnessy, “Statement before the Senate Armed Services Committee,” February 13, 2020, General Terrence J. O’Shaughnessy, “Statement before the Senate Armed Services Committee,” February 13, 2020,
at https://www.armed-services.senate.gov/hearings/20-02-13-united-states-northern-command-and-united-states-at https://www.armed-services.senate.gov/hearings/20-02-13-united-states-northern-command-and-united-states-
strategic-command. strategic-command.
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~~nuclear-capable HGV95—launched by a Long March rocket—in August 2021.96 In contrast to the~~
~~ballistic missiles that China has previously used to launch HGVs, the Long March, a fractional~~
104 It is not clear if this nuclear-capable HGV is the same model as that referenced by General O’Shaughnessy. 105 Demetri Sevastopulo and Kathrin Hille, “China tests new space capability with hypersonic missile,” October 16, 2021, at https://www.ft.com/content/ba0a3cde-719b-4040-93cb-a486e1f843fb. China’s Foreign Ministry Spokesperson Zhao Lijian has stated that “this was a routine test of [a] space vehicle,” rather than a test of a nuclear-capable HGV. Zhao Lijian, “Remarks at Regular Press Conference,” Ministry of Foreign Affairs of the People’s Republic of China, October 18, 2021, at https://www.fmprc.gov.cn/mfa_eng/xwfw_665399/s2510_665401/t1915130.shtml. Congressional Research Service 16 Hypersonic Weapons: Background and Issues for Congress fractional orbital bombardment system (FOBS), launches the HGV into orbit before the HGV de-orbits to orbital bombardment system (FOBS), launches the HGV into orbit before the HGV de-orbits to
its target. This could provide China with a space-based global strike capability and further reduce its target. This could provide China with a space-based global strike capability and further reduce
the amount of target warning time prior to a strike.the amount of target warning time prior to a strike.97106
China has also demonstrated a growing interest in Russian advances in hypersonic weapons China has also demonstrated a growing interest in Russian advances in hypersonic weapons
technology, conducting flight tests of a hypersonic-glide vehicle (HGV) only days after Russia technology, conducting flight tests of a hypersonic-glide vehicle (HGV) only days after Russia
tested its own system.tested its own system.98107 Furthermore, a January 2017 report found that over half of open-source Furthermore, a January 2017 report found that over half of open-source
Chinese papers on hypersonic weapons include references to Russian weapons programs.Chinese papers on hypersonic weapons include references to Russian weapons programs.99108 This This
could indicate that China is increasingly considering hypersonic weapons within a regional could indicate that China is increasingly considering hypersonic weapons within a regional
context. Indeed, some analysts believe that China may be planning to mate conventionally armed context. Indeed, some analysts believe that China may be planning to mate conventionally armed
HGVs with the DF-21 and DF-26 ballistic missiles in support of an anti-access/area denial HGVs with the DF-21 and DF-26 ballistic missiles in support of an anti-access/area denial
strategy.strategy.~~100~~109
Programs
China has conducted a number of successful tests of the DF-17, a medium-range ballistic missile China has conducted a number of successful tests of the DF-17, a medium-range ballistic missile
specifically designed to launch HGVs. U.S. intelligence analysts assess that the missile has a specifically designed to launch HGVs. U.S. intelligence analysts assess that the missile has a
range of approximately 1,000 to 1,500 miles and may now be deployed.range of approximately 1,000 to 1,500 miles and may now be deployed.~~101~~110 China has also tested China has also tested
the DF-41 intercontinental ballistic missile, which could be modified to carry a conventional or the DF-41 intercontinental ballistic missile, which could be modified to carry a conventional or
nuclear HGV, according to a report by a U.S. Congressional commission. The development of the nuclear HGV, according to a report by a U.S. Congressional commission. The development of the
DF-41 thus “significantly increases the [Chinese] rocket force’s nuclear threat to the U.S. DF-41 thus “significantly increases the [Chinese] rocket force’s nuclear threat to the U.S.
mainland,” the report states.mainland,” the report states.~~102~~111
China has tested the DF-ZF HGV (previously referred to as the WU-14) at least nine times since China has tested the DF-ZF HGV (previously referred to as the WU-14) at least nine times since
2014. U.S. defense officials have reportedly identified the range of the DF-ZF as approximately 2014. U.S. defense officials have reportedly identified the range of the DF-ZF as approximately

~~95 It is not clear if this nuclear-capable HGV is the same model as that referenced by General O’Shaughnessy.~~
~~96 Demetri Sevastopulo and Kathrin Hille, “China tests new space capability with hypersonic missile,” October 16,~~
~~2021, at https://www.ft.com/content/ba0a3cde-719b-4040-93cb-a486e1f843fb. China’s Foreign Ministry Spokesperson~~
~~Zhao Lijian has stated that “this was a routine test of [a] space vehicle,” rather than a test of a nuclear-capable HGV.~~
~~Zhao Lijian, “Remarks at Regular Press Conference,” Ministry of Foreign Affairs of the People’s Republic of China,~~
~~October 18, 2021, at https://www.fmprc.gov.cn/mfa_eng/xwfw_665399/s2510_665401/t1915130.shtml.~~
971,200 miles and have stated that the vehicle may be capable of performing “extreme maneuvers” during flight.112 China reportedly fielded the DF-ZF in 2020.113 106 Greg Hadley, “Kendall: China Has Potential to Strike Earth from Space,” Greg Hadley, “Kendall: China Has Potential to Strike Earth from Space,” Air Force Magazine, September 20, 2021, , September 20, 2021,
at https://www.airforcemag.com/global-strikes-space-china-frank-kendall/. at https://www.airforcemag.com/global-strikes-space-china-frank-kendall/.
98107 Lora Saalman, “China’s Calculus on Hypersonic Glide.” Lora Saalman, “China’s Calculus on Hypersonic Glide.”
99108 Lora Saalman, “Factoring Russia into the US-China Equation on Hypersonic Glide Vehicles,” SIPRI, January 2017, Lora Saalman, “Factoring Russia into the US-China Equation on Hypersonic Glide Vehicles,” SIPRI, January 2017,
at https://www.sipri.org/sites/default/files/Factoring-Russia-into-US-Chinese-equation-hypersonic-glide-vehicles.pdf. at https://www.sipri.org/sites/default/files/Factoring-Russia-into-US-Chinese-equation-hypersonic-glide-vehicles.pdf.
~~100~~109 Lora Saalman, “China’s Calculus on Hypersonic Glide”; and Malcolm Claus and Andrew Tate, “Chinese Lora Saalman, “China’s Calculus on Hypersonic Glide”; and Malcolm Claus and Andrew Tate, “Chinese
hypersonic programme reflects regional priorities,” hypersonic programme reflects regional priorities,” Jane’s (subscription required), March 12, 2019, at (subscription required), March 12, 2019, at
https://janes.ihs.com/Janes/Display/FG_1731069-JIR. https://janes.ihs.com/Janes/Display/FG_1731069-JIR.
~~101~~110 Ankit Panda, “Introducing the DF-17: China’s Newly Tested Ballistic Missile Armed with a Hypersonic Glide Ankit Panda, “Introducing the DF-17: China’s Newly Tested Ballistic Missile Armed with a Hypersonic Glide
Vehicle,” Vehicle,” The National Interest, December 28, 2017, at https://thediplomat.com/2017/12/introducing-the-df-17-chinas-, December 28, 2017, at https://thediplomat.com/2017/12/introducing-the-df-17-chinas-
newly-tested-ballistic-missile-armed-with-a-hypersonic-glide-vehicle/; and Bill Gertz, “China’s new hypersonic newly-tested-ballistic-missile-armed-with-a-hypersonic-glide-vehicle/; and Bill Gertz, “China’s new hypersonic
missile,” missile,” Washington Times, October 2, 2019, at https://www.washingtontimes.com/news/2019/oct/2/china-shows-df-, October 2, 2019, at https://www.washingtontimes.com/news/2019/oct/2/china-shows-df-
17-hypersonic-missile/. 17-hypersonic-missile/.
~~102~~111 U.S.-China Economic and Security Review Commission 2018 Annual Report, p. 235, at https://www.uscc.gov/sites/, p. 235, at https://www.uscc.gov/sites/
default/files/annual_reports/2018%20Annual%20Report%20to%20Congress.pdf. default/files/annual_reports/2018%20Annual%20Report%20to%20Congress.pdf.
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~~1,200 miles and have stated that the vehicle may be capable of performing “extreme maneuvers”~~
~~during flight.103 China reportedly fielded the DF-ZF in 2020.104~~
112 “Gliding missiles that fly faster than Mach 5 are coming,” The Economist, April 6, 2019, at https://www.economist.com/science-and-technology/2019/04/06/gliding-missiles-that-fly-faster-than-mach-5-are-coming; and Franz-Stefan Gady, “China Tests New Weapon Capable of Breaching US Missile Defense Systems,” The Diplomat, April 28, 2016, at https://thediplomat.com/2016/04/china-tests-new-weapon-capable-of-breaching-u-s-missile-defense-systems/. 113 Department of Defense, Military and Security Developments Involving the People’s Republic of China 2021, p. 60, at https://media.defense.gov/2021/Nov/03/2002885874/-1/-1/0/2021-CMPR-FINAL.PDF. Congressional Research Service 17 link to page 22 Hypersonic Weapons: Background and Issues for Congress According to U.S. defense officials, China also successfully tested Starry Sky-2 (or Xing Kong- According to U.S. defense officials, China also successfully tested Starry Sky-2 (or Xing Kong-
2), a nuclear-capable hypersonic vehicle prototype, in August 2018.2), a nuclear-capable hypersonic vehicle prototype, in August 2018.~~105~~114 China claims the vehicle China claims the vehicle
reached top speeds of Mach 6 and executed a series of in-flight maneuvers before landing.reached top speeds of Mach 6 and executed a series of in-flight maneuvers before landing.~~106~~115
Unlike the DF-ZF, Starry Sky-2 is a “waverider” that uses powered flight after launch and derives Unlike the DF-ZF, Starry Sky-2 is a “waverider” that uses powered flight after launch and derives
lift from its own shockwaves. Some reports indicate that the Starry Sky-2 could be operational by lift from its own shockwaves. Some reports indicate that the Starry Sky-2 could be operational by
2025.2025.~~107~~116 U.S. officials have declined to comment on the program. U.S. officials have declined to comment on the program.~~108~~117
Infrastructure
China has a robust research and development infrastructure devoted to hypersonic weapons. China has a robust research and development infrastructure devoted to hypersonic weapons.
Then-USD(R&E) Michael Griffin stated in March 2018 that China has conducted 20 times as Then-USD(R&E) Michael Griffin stated in March 2018 that China has conducted 20 times as
many hypersonic tests as the United States.many hypersonic tests as the United States.~~109~~118 China tested three hypersonic vehicle models China tested three hypersonic vehicle models
(D18-1S, D18-2S, and D18-3S)—each with different aerodynamic properties—in September (D18-1S, D18-2S, and D18-3S)—each with different aerodynamic properties—in September
2018.2018.~~110~~119 Analysts believe that these tests could be designed to help China develop weapons that Analysts believe that these tests could be designed to help China develop weapons that
fly at variable speeds, including hypersonic speeds. Similarly, China has used the Lingyun Mach fly at variable speeds, including hypersonic speeds. Similarly, China has used the Lingyun Mach
6+ high-speed engine, or “scramjet,” test bed 6+ high-speed engine, or “scramjet,” test bed (Figure 3) to research thermal resistant components to research thermal resistant components
and hypersonic cruise missile technologies.and hypersonic cruise missile technologies.~~111~~120 114

~~103 “Gliding missiles that fly faster than Mach 5 are coming,” The Economist, April 6, 2019, at~~
~~https://www.economist.com/science-and-technology/2019/04/06/gliding-missiles-that-fly-faster-than-mach-5-are-~~
~~coming; and Franz-Stefan Gady, “China Tests New Weapon Capable of Breaching US Missile Defense Systems,”~~ ~~The~~
~~Diplomat, April 28, 2016, at https://thediplomat.com/2016/04/china-tests-new-weapon-capable-of-breaching-u-s-~~
~~missile-defense-systems/.~~
~~104 Department of Defense, Military and Security Developments Involving the People’s Republic of China 2021, p. 60,~~
~~at https://media.defense.gov/2021/Nov/03/2002885874/-1/-1/0/2021-CMPR-FINAL.PDF.~~
~~105~~ Office of the Secretary of Defense, Office of the Secretary of Defense, Annual Report to Congress: Military and Security Developments Involving the
People’s Republic of China 2019, May 2, 2019, p. 44, at https://media.defense.gov/2019/May/02/2002127082/-1/-1/1/May 2, 2019, p. 44, at https://media.defense.gov/2019/May/02/2002127082/-1/-1/1/
2019_CHINA_MILITARY_POWER_REPORT.pdf. 2019_CHINA_MILITARY_POWER_REPORT.pdf.
~~106~~115 Jessie Yeung, “China claims to have successfully tested its first hypersonic aircraft, Jessie Yeung, “China claims to have successfully tested its first hypersonic aircraft, CNN, August 7, 2018, at , August 7, 2018, at
https://www.cnn.com/2018/08/07/china/china-hypersonic-aircraft-intl/index.html. https://www.cnn.com/2018/08/07/china/china-hypersonic-aircraft-intl/index.html.
~~107~~116 U.S.-China Economic and Security Review Commission Report 2015,, p. 20. p. 20.
~~108~~117 Bill Gertz, “China Reveals Test of New Hypersonic Missile,” Bill Gertz, “China Reveals Test of New Hypersonic Missile,” The Washington Free Beacon, August 10, 2018, at , August 10, 2018, at
https://freebeacon.com/national-security/chinas-reveals-test-new-hypersonic-missile/. https://freebeacon.com/national-security/chinas-reveals-test-new-hypersonic-missile/.
~~109~~118 U.S.-China Economic and Security Review Commission Report 2015, p. 20. , p. 20.
~~110~~119 Malcolm Claus and Andrew Tate, “Chinese hypersonic programme reflects regional priorities,” Malcolm Claus and Andrew Tate, “Chinese hypersonic programme reflects regional priorities,” Jane’s (subscription (subscription
required), March 12, 2019, at https://janes.ihs.com/Janes/Display/FG_1731069-JIR. required), March 12, 2019, at https://janes.ihs.com/Janes/Display/FG_1731069-JIR.
~~111~~120 Jeffrey Lin and P.W. Singer, “China’s hypersonic military projects include spaceplanes and rail guns,” Jeffrey Lin and P.W. Singer, “China’s hypersonic military projects include spaceplanes and rail guns,” Popular
Mechanics, June 26, 2018, at https://www.popsci.com/chinas-hypersonic-work-speeds-up. , June 26, 2018, at https://www.popsci.com/chinas-hypersonic-work-speeds-up.
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Figure 3. Lingyun-1 Hypersonic Cruise Missile Prototype

Source: Photo accompanying Drake Long, “China reveals Lingyun-1 hypersonic missile at National Science and Photo accompanying Drake Long, “China reveals Lingyun-1 hypersonic missile at National Science and
Technology expo,” Technology expo,” The Defense Post, May 21, 2018. , May 21, 2018.
According to According to Jane’s Defence Weekly, “China is also investing heavily in hypersonic ground , “China is also investing heavily in hypersonic ground
testing facilities.”testing facilities.”~~112~~121 For example, the China Aerodynamics Research and Development Center For example, the China Aerodynamics Research and Development Center
claims to have 18 wind tunnels, while the China Academy of Aerospace Aerodynamics is known claims to have 18 wind tunnels, while the China Academy of Aerospace Aerodynamics is known
to operate at least three hypersonic wind tunnels—the FD-02, FD-03, and FD-07—capable of to operate at least three hypersonic wind tunnels—the FD-02, FD-03, and FD-07—capable of
reaching speeds of Mach 8, Mach 10, and Mach 12, respectively.reaching speeds of Mach 8, Mach 10, and Mach 12, respectively.~~113~~122 China also operates the JF-12 China also operates the JF-12
hypersonic wind tunnel, which reaches speeds of between Mach 5 and Mach 9 and the FD-21 hypersonic wind tunnel, which reaches speeds of between Mach 5 and Mach 9 and the FD-21
hypersonic wind tunnel, which reaches speeds of between Mach 10 and Mach 15.hypersonic wind tunnel, which reaches speeds of between Mach 10 and Mach 15.~~114~~123 It will It will
reportedly complete construction of the JF-22 wind tunnel, capable of reaching speeds of Mach reportedly complete construction of the JF-22 wind tunnel, capable of reaching speeds of Mach
30, in 2022.30, in 2022.~~115~~124 In addition, China is known to have tested hypersonic weapons at the Jiuquan In addition, China is known to have tested hypersonic weapons at the Jiuquan
Satellite Launch Center and the Taiyuan Satellite Launch Center. Satellite Launch Center and the Taiyuan Satellite Launch Center.

~~112~~121 Andrew Tate, “China conducts further tests with hypersonic vehicles,” Andrew Tate, “China conducts further tests with hypersonic vehicles,” Jane’s Defence Weekly (subscription (subscription
required), October 2, 2018, at https://customer.janes.com/DefenceWeekly/Display/FG_1120806-JDW. required), October 2, 2018, at https://customer.janes.com/DefenceWeekly/Display/FG_1120806-JDW.
~~113~~122 Kelvin Wong, “China claims successful test of hypersonic waverider,” Kelvin Wong, “China claims successful test of hypersonic waverider,” Jane’s (subscription required), August 10, at (subscription required), August 10, at
2018, https://janes.ihs.com/Janes/Display/FG_1002295-JDW; and Ellen Nakashima and Gerry Shih, “China builds 2018, https://janes.ihs.com/Janes/Display/FG_1002295-JDW; and Ellen Nakashima and Gerry Shih, “China builds
advanced weapons systems using American chip technology,” advanced weapons systems using American chip technology,” Washington Post, April 9, 2021. , April 9, 2021.
~~114~~ 123 Jeffrey Lin and P.W. Singer, “A look at China’s most exciting hypersonic aerospace programs,” Jeffrey Lin and P.W. Singer, “A look at China’s most exciting hypersonic aerospace programs,” Popular Science, ,
April 18, 2017, at https://www.popsci.com/chinas-hypersonic-technology. April 18, 2017, at https://www.popsci.com/chinas-hypersonic-technology.
~~115~~124 Andrew Tate, “China’s new hypersonic wind tunnel expected to be ready next year,” Andrew Tate, “China’s new hypersonic wind tunnel expected to be ready next year,” Janes Defence Weekly
(subscription required), August 24, 2021, at https://www.janes.com/defence-news/news-detail/chinas-new-hypersonic-(subscription required), August 24, 2021, at https://www.janes.com/defence-news/news-detail/chinas-new-hypersonic-
wind-tunnel-expected-to-be-ready-next-year. wind-tunnel-expected-to-be-ready-next-year.
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Global Hypersonic Weapons Programs
Although the United States, Russia, and China possess the most advanced hypersonic weapons programs, a Although the United States, Russia, and China possess the most advanced hypersonic weapons programs, a
number of other countries—including Australia, India, France, Germany, number of other countries—including Australia, India, France, Germany, South Korea, North Korea, and Japan—are also developing and Japan—are also developing
hypersonic weapons technology. Since 2007, the United States has col aborated with Australia on the Hypersonic hypersonic weapons technology. Since 2007, the United States has col aborated with Australia on the Hypersonic
International Flight Research Experimentation (HIFiRE) program to develop hypersonic technologies. The most International Flight Research Experimentation (HIFiRE) program to develop hypersonic technologies. The most
recent HIFiRE test, successful y conducted in July 2017, explored the flight dynamics of a Mach 8 hypersonic glide recent HIFiRE test, successful y conducted in July 2017, explored the flight dynamics of a Mach 8 hypersonic glide
vehicle, while previous tests explored scramjet engine technologies. HIFiRE’s successor, the Southern Cross vehicle, while previous tests explored scramjet engine technologies. HIFiRE’s successor, the Southern Cross
Integrated Flight Research Experiment (SCIFiRE) program, is to further develop hypersonic air-breathing Integrated Flight Research Experiment (SCIFiRE) program, is to further develop hypersonic air-breathing
technologies. SCIFiRE demonstration tests are expected by the mid-2020s. In addition to the Woomera Test technologies. SCIFiRE demonstration tests are expected by the mid-2020s. In addition to the Woomera Test
Range facilities—one of the largest weapons test facilities in the world—Australia reportedly operates seven Range facilities—one of the largest weapons test facilities in the world—Australia reportedly operates seven
hypersonic wind tunnels and is capable of testing speeds of up to Mach 30. hypersonic wind tunnels and is capable of testing speeds of up to Mach 30.
India has similarly col aborated with Russia on the development of BrahMos II, a Mach 7 hypersonic cruise missile. India has similarly col aborated with Russia on the development of BrahMos II, a Mach 7 hypersonic cruise missile.
Although BrahMos II was initially intended to be fielded in 2017, news reports indicate that the program faces Although BrahMos II was initially intended to be fielded in 2017, news reports indicate that the program faces
significant delays and is now scheduled to achieve initial operational capability between 2025 and 2028. Reportedly, significant delays and is now scheduled to achieve initial operational capability between 2025 and 2028. Reportedly,
India is also developing an indigenous, dual-capable hypersonic cruise missile as part of its Hypersonic Technology India is also developing an indigenous, dual-capable hypersonic cruise missile as part of its Hypersonic Technology
Demonstrator Vehicle program and successful y tested a Mach 6 scramjet in June 2019 and September 2020. India Demonstrator Vehicle program and successful y tested a Mach 6 scramjet in June 2019 and September 2020. India
operates approximately 12 hypersonic wind tunnels and is capable of testing speeds of up to Mach 13. operates approximately 12 hypersonic wind tunnels and is capable of testing speeds of up to Mach 13.
France also has col aborated and contracted with Russia on the development of hypersonic technology. Although France also has col aborated and contracted with Russia on the development of hypersonic technology. Although
France has been investing in hypersonic technology research since the 1990s, it has only recently announced its France has been investing in hypersonic technology research since the 1990s, it has only recently announced its
intent to weaponize the technology. Under the V-max (Experimental Maneuvering Vehicle) program, France plans intent to weaponize the technology. Under the V-max (Experimental Maneuvering Vehicle) program, France plans
to modify its air-to-surface ASN4G supersonic missile for hypersonic flight by 2022. Some analysts believe that the to modify its air-to-surface ASN4G supersonic missile for hypersonic flight by 2022. Some analysts believe that the
V-max program is intended to provide France with a strategic nuclear weapon. France operates five hypersonic V-max program is intended to provide France with a strategic nuclear weapon. France operates five hypersonic
wind tunnels and is capable of testing speeds of up to Mach 21. wind tunnels and is capable of testing speeds of up to Mach 21.
Germany successful y tested an experimental hypersonic glide vehicle (SHEFEX II) in 2012; however, reports Germany successful y tested an experimental hypersonic glide vehicle (SHEFEX II) in 2012; however, reports
indicate that Germany may have pul ed funding for the program. German defense contractor DLR continues to indicate that Germany may have pul ed funding for the program. German defense contractor DLR continues to
research and test hypersonic vehicles as part of the European Union’s ATLLAS II project, which seeks to design a research and test hypersonic vehicles as part of the European Union’s ATLLAS II project, which seeks to design a
Mach 5-6 vehicle. Germany operates three hypersonic wind tunnels and is capable of testing speeds of up to Mach 5-6 vehicle. Germany operates three hypersonic wind tunnels and is capable of testing speeds of up to
Mach 11. Mach 11.
In addition, South Korea reportedly has been developing a ground-launched Mach 6+ hypersonic cruise missile, Hycore, since 2018 and plans to test the missile in 2022. According to Janes, South Korea is developing the missile “in response to growing concern about North Korea military modernization” and plans to eventually develop sea- and air-launched variants. Although North Korea tested the Hwasong-8—which it identifies as a hypersonic glide vehicle—in September 2021, reports indicate that the vehicle may have reached speeds of only Mach 3. Similarly, North Korea claims to have tested a second hypersonic weapon in January 2022; however, experts believe that that weapon may instead be a maneuvering reentry vehicle. Finally, Japan is developing the Hypersonic Cruise Missile (HCM) and the Hyper Velocity Gliding Projectile Finally, Japan is developing the Hypersonic Cruise Missile (HCM) and the Hyper Velocity Gliding Projectile
(HVGP). According to(HVGP). According to Jane’s, Japan invested $122 mil ion in HVGP in FY2019. It reportedly plans to field HVGPs , Japan invested $122 mil ion in HVGP in FY2019. It reportedly plans to field HVGPs
for area suppression and neutralizing aircraft carriers. HVGP is expected to enter service in 2026, with a more for area suppression and neutralizing aircraft carriers. HVGP is expected to enter service in 2026, with a more
advanced version available by 2030, while HCM is expected to enter service in 2030. The Japan Aerospace advanced version available by 2030, while HCM is expected to enter service in 2030. The Japan Aerospace
Exploration Agency operates three hypersonic wind tunnels, with two additional facilities at Mitsubishi Heavy Exploration Agency operates three hypersonic wind tunnels, with two additional facilities at Mitsubishi Heavy
Industries and the University of Tokyo. Industries and the University of Tokyo.
Other countries—including Iran, Israel, Other countries—including Iran, Israel, ~~South Korea,~~ and Brazil—have conducted foundational research on and Brazil—have conducted foundational research on
hypersonic airflows and propulsion systems, but may not be pursuing a hypersonic weapons capability at this time. hypersonic airflows and propulsion systems, but may not be pursuing a hypersonic weapons capability at this time.
In addition, a number of countriesIn addition, a number of countries~~—including North Korea—~~ are testing increasingly maneuverable systems that are testing increasingly maneuverable systems that
travel at hypersonic speeds but that do not qualify as “hypersonic weapons” as defined in this report. travel at hypersonic speeds but that do not qualify as “hypersonic weapons” as defined in this report.
Note: For ~~additional~~ information about ~~global~~South Korea’s hypersonic weapons programs, see ~~Richard H. Speier et al., Hypersonic~~
~~Missile Proliferation. For information about Japan’s hypersonic weapons research and development plans~~Jon Grevatt and Rahul Udoshi, “South Korea develops Hycore hypersonic cruise missile,” Janes (subscription required), January 25, 2022. For information about North Korea’s hypersonic weapons programs, see Choi Soo-hyang, “N. Korea's ‘hypersonic missile’ appears to be at early stage of development: JCS,” Yonhap News Agency, September 29, 2021; and Ankit Panda, “The real danger of North Korea’s new hypersonic missile is not its speed,” NK News, January 10, 2022. For information about Japan’s hypersonic weapons programs, see Mike Yeo,
“Japan unveils its hypersonic weapons plans,” Defense News, March 14, 2020.

For additional information about global hypersonic weapons programs, see Richard H. Speier et al., Hypersonic Missile Proliferation. Congressional Research Service 20 Hypersonic Weapons: Background and Issues for Congress Issues for Congress
As Congress reviews the Pentagon’s plans for U.S. hypersonic weapons programs during the As Congress reviews the Pentagon’s plans for U.S. hypersonic weapons programs during the
annual authorization and appropriations process, it might consider a number of questions about annual authorization and appropriations process, it might consider a number of questions about
the rationale for hypersonic weapons, their expected costs, budget and management, and their the rationale for hypersonic weapons, their expected costs, budget and management, and their
implications for strategic stability and arms control. This section provides an overview of some of implications for strategic stability and arms control. This section provides an overview of some of
these questions. these questions.
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~~Hypersonic Weapons: Background and Issues for Congress~~

Mission Requirements
Although the Department of Defense is funding a number of hypersonic weapons programs, it has Although the Department of Defense is funding a number of hypersonic weapons programs, it has
not established any programs of record, suggesting that it may not have approved requirements not established any programs of record, suggesting that it may not have approved requirements
for hypersonic weapons or long-term funding plans.for hypersonic weapons or long-term funding plans.~~116~~125 Indeed, as Principal Director for Indeed, as Principal Director for
Hypersonics (USD[R&E]) Mike White has stated, DOD has not yet made a decision to acquire Hypersonics (USD[R&E]) Mike White has stated, DOD has not yet made a decision to acquire
hypersonic weapons and is instead developing prototypes to “[identify] the most viable hypersonic weapons and is instead developing prototypes to “[identify] the most viable
overarching weapon system concepts to choose from and then make a decision based on success overarching weapon system concepts to choose from and then make a decision based on success
and challenges.”and challenges.”~~117~~126
Given the lack of mission requirements, DOD officials have expressed a number of competing Given the lack of mission requirements, DOD officials have expressed a number of competing
perspectives about the potential costs and intended quantities of U.S. hypersonic weapons. For perspectives about the potential costs and intended quantities of U.S. hypersonic weapons. For
example, Secretary of the Air Force Frank Kendall has stated that “hypersonics are not going to example, Secretary of the Air Force Frank Kendall has stated that “hypersonics are not going to
be cheap anytime soon ... [and thus] we’re more likely to have relatively small inventories of be cheap anytime soon ... [and thus] we’re more likely to have relatively small inventories of
[hypersonic missiles] than large ones.”[hypersonic missiles] than large ones.”~~118~~127 Conversely, a number of other senior defense officials Conversely, a number of other senior defense officials
have stated that DOD intends to buy large quantities of hypersonic weapons. Then-DOD Director have stated that DOD intends to buy large quantities of hypersonic weapons. Then-DOD Director
of Defense Research & Engineering Mark Lewis has noted that DOD wants “to deliver of Defense Research & Engineering Mark Lewis has noted that DOD wants “to deliver
hypersonics at scale.... That means hundreds of weapons in a short period of time in the hands of hypersonics at scale.... That means hundreds of weapons in a short period of time in the hands of
the warfighter.”the warfighter.”~~119~~128 Similarly, Principal Director for Hypersonics Mike White has stated that DOD Similarly, Principal Director for Hypersonics Mike White has stated that DOD
seeks to “[produce] hypersonics in mass, because you have to be able to deliver capability in seeks to “[produce] hypersonics in mass, because you have to be able to deliver capability in
meaningful numbers, even to defeat the high-end targets.”meaningful numbers, even to defeat the high-end targets.”~~120~~129 These perspectives appear to be These perspectives appear to be
grounded in differing assumptions about the affordability of hypersonic weapons. Likewise, they grounded in differing assumptions about the affordability of hypersonic weapons. Likewise, they
are likely to hold different implications for the unit cost of the weapons. are likely to hold different implications for the unit cost of the weapons.
As Congress conducts oversight of U.S. hypersonic weapons programs, it may seek to obtain As Congress conducts oversight of U.S. hypersonic weapons programs, it may seek to obtain
information about DOD’s evaluation of potential mission sets for hypersonic weapons, a cost information about DOD’s evaluation of potential mission sets for hypersonic weapons, a cost
analysis of hypersonic weapons and alternative means of executing potential mission sets, and an analysis of hypersonic weapons and alternative means of executing potential mission sets, and an
assessment of the enabling technologies—such as space-based sensors or autonomous command assessment of the enabling technologies—such as space-based sensors or autonomous command
and control systems—that may be required to employ or defend against hypersonic weapons. For and control systems—that may be required to employ or defend against hypersonic weapons. For
example, Section 1671 of the FY2021 NDAA (P.L. 116-283) directs the Chairman of the Joint example, Section 1671 of the FY2021 NDAA (P.L. 116-283) directs the Chairman of the Joint
~~Chiefs of Staff, in coordination with the Under Secretary of Defense for Policy, to submit to the~~
~~congressional defense committees a report on strategic hypersonic weapons, including “a~~
~~description of how the requirements for land and sea-based hypersonic weapons will be addressed~~
~~with the Joint Requirements Oversight Council, and how such requirements will be formally~~
~~provided to the military departments procuring such weapons.” This report is to additionally~~
~~include “the potential target sets for hypersonic weapons ... and the required mission planning to~~
~~support targeting by the United States Strategic Command and other combatant commands.”~~

~~116~~ 125 Steve Trimble, “New Long-Term Pentagon Plan Boosts Hypersonics.” Steve Trimble, “New Long-Term Pentagon Plan Boosts Hypersonics.”
~~117~~126 Steve Trimble, “New Long-Term Pentagon Plan Boosts Hypersonics.” Steve Trimble, “New Long-Term Pentagon Plan Boosts Hypersonics.”
~~118~~127 John A. Tirpak, “Only Small Inventories of Hypersonic Missiles in USAF’s Future, Due to Cost,” John A. Tirpak, “Only Small Inventories of Hypersonic Missiles in USAF’s Future, Due to Cost,” Air Force
Magazine, February 15, 2022, at https://www.airforcemag.com/only-small-inventories-of-hypersonic-missiles-in-usafs-, February 15, 2022, at https://www.airforcemag.com/only-small-inventories-of-hypersonic-missiles-in-usafs-
future-due-to-cost/. future-due-to-cost/.
~~119~~128 Sydney J. Freedberg Sydney J. Freedberg, Jr., “Hypersonics: DoD Wants ‘Hundreds of Weapons’ ASAP,” Jr., “Hypersonics: DoD Wants ‘Hundreds of Weapons’ ASAP,” Breaking Defense, April 24, , April 24,
2020, at https://breakingdefense.com/2020/04/hypersonics-dod-wants-hundreds-of-weapons-asap/. 2020, at https://breakingdefense.com/2020/04/hypersonics-dod-wants-hundreds-of-weapons-asap/.
~~120~~129 “Hypersonic Strike and Defense: A Conversation with Mike White,” Center for Strategic and International Studies, “Hypersonic Strike and Defense: A Conversation with Mike White,” Center for Strategic and International Studies,
June 10, 2021, at https://www.csis.org/analysis/hypersonic-strike-and-defense-conversation-mike-white. See also Jon June 10, 2021, at https://www.csis.org/analysis/hypersonic-strike-and-defense-conversation-mike-white. See also Jon
Harper, “Just In: Pentagon to Spend Billions Mass-Producing Hypersonic Weapons,” Harper, “Just In: Pentagon to Spend Billions Mass-Producing Hypersonic Weapons,” National Defense Magazine, ,
March 4, 2020, at https://www.nationaldefensemagazine.org/articles/2020/3/4/pentagon-to-spend-billions-mass-March 4, 2020, at https://www.nationaldefensemagazine.org/articles/2020/3/4/pentagon-to-spend-billions-mass-
producing-hypersonic-weapons. producing-hypersonic-weapons.
Congressional Research Service Congressional Research Service

2021 Hypersonic Weapons: Background and Issues for Congress Chiefs of Staff, in coordination with the Under Secretary of Defense for Policy, to submit to the congressional defense committees a report on strategic hypersonic weapons, including “a description of how the requirements for land and sea-based hypersonic weapons will be addressed with the Joint Requirements Oversight Council, and how such requirements will be formally provided to the military departments procuring such weapons.” This report is to additionally include “the potential target sets for hypersonic weapons ... and the required mission planning to support targeting by the United States Strategic Command and other combatant commands.”

~~Hypersonic Weapons: Background and Issues for Congress~~

Funding and Management Considerations
Principal Director for Hypersonics Mike White has noted that DOD is prioritizing offensive Principal Director for Hypersonics Mike White has noted that DOD is prioritizing offensive
programs while it determines “the path forward to get a robust defensive strategy.”programs while it determines “the path forward to get a robust defensive strategy.”~~121~~130 This This
approach is reflected in DOD’s recent budget requests. For example, DOD requested $approach is reflected in DOD’s recent budget requests. For example, DOD requested $~~247.9~~225.5
million for hypersonic defense programs and $million for hypersonic defense programs and $~~3.8~~4.7 billion for hypersonic weapons programs in billion for hypersonic weapons programs in
~~FY2022.122~~FY2023.131 Similarly, in Similarly, in ~~FY2021~~FY2022, DOD requested $, DOD requested $~~206.8~~247.9 million for hypersonic defense million for hypersonic defense
programs and $3.programs and $3.28 billion for hypersonic weapons programs. billion for hypersonic weapons programs.~~123~~132
Although the Defense Subcommittees of the Appropriations Committees increased FY2020 Although the Defense Subcommittees of the Appropriations Committees increased FY2020
appropriations for both hypersonic offense and defense above the FY2020 request, they expressed appropriations for both hypersonic offense and defense above the FY2020 request, they expressed
concerns, noting in their joint explanatory statement of H.R. 1158 “that the rapid growth in concerns, noting in their joint explanatory statement of H.R. 1158 “that the rapid growth in
hypersonic research has the potential to result in stove-piped, proprietary systems that duplicate hypersonic research has the potential to result in stove-piped, proprietary systems that duplicate
capabilities and increase costs.”capabilities and increase costs.”~~124~~133 To mitigate this concern, they appropriated $100 million for To mitigate this concern, they appropriated $100 million for
DOD to establish a Joint Hypersonics Transition Office (JHTO) to “develop and implement an DOD to establish a Joint Hypersonics Transition Office (JHTO) to “develop and implement an
integrated science and technology roadmap for hypersonics” and “establish a university integrated science and technology roadmap for hypersonics” and “establish a university
consortium for hypersonic research and workforce development” in support of DOD efforts.consortium for hypersonic research and workforce development” in support of DOD efforts.~~125~~
~~DOD established the JHTO in April 2020 and announced on October 26, 2020, that it awarded~~
~~Texas A&M University with a $20 million contract—renewable for up to $100 million—to~~
~~manage a University Consortium for Applied Hypersonics (UCAH).126 UCAH is to be overseen~~
~~by a group of academic researchers from Texas A&M University, the Massachusetts Institute of~~
~~Technology, the University of Minnesota, the University of Illinois at Urbana-Champaign, the~~
~~University of Arizona, the University of Tennessee Space Institute, Morgan State University, the~~
~~California Institute of Technology, Purdue University, the University of California-Los Angeles,~~
~~and the Georgia Institute of Technology.127 The consortium is to “facilitate transitioning academic~~
134
~~121~~130 Aaron Mehta, “Is the Pentagon Moving Quickly Enough on Hypersonic Defense?” Aaron Mehta, “Is the Pentagon Moving Quickly Enough on Hypersonic Defense?” Defense News, March 21, 2019, , March 21, 2019,
at https://www.defensenews.com/pentagon/2019/03/21/is-the-pentagon-moving-quickly-enough-on-hypersonic-at https://www.defensenews.com/pentagon/2019/03/21/is-the-pentagon-moving-quickly-enough-on-hypersonic-
defense/. defense/.
~~122~~131 Department of Defense Fiscal Year (FY) Department of Defense Fiscal Year (FY) ~~2022~~2023 Budget Estimates, Missile Defense Agency Defense-Wide Budget Estimates, Missile Defense Agency Defense-Wide
Justification Book Volume 2a of 5, p. Justification Book Volume 2a of 5, p. ~~569~~631, at , at
https://comptroller.defense.gov/Portals/45/Documents/defbudget/https://comptroller.defense.gov/Portals/45/Documents/defbudget/~~fy2022/~~fy2023/budget_justification/pdfs/03_RDT_and_E/budget_justification/pdfs/03_RDT_and_E/RD
~~TE_Vol2_MDA_RDTE_PB22_Justification_Book.pdf.~~
~~123 Department of Defense Fiscal Year (FY) 2021~~RDTE_Vol2_MDA_RDTE_PB23_Justification_Book.pdf; and Defense Budget Overview: United States Department of Defense Fiscal Year 2023 Budget Request, Office of the Under Secretary of Defense (Comptroller)/Chief Financial Officer, April 2022, p. 2-16, at https://comptroller.defense.gov/Portals/45/Documents/defbudget/FY2023/FY2023_Budget_Request_Overview_Book.pdf. 132 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Missile Defense Agency Defense-Wide Budget Estimates, Missile Defense Agency Defense-Wide
Justification Book Volume 2a of 5, p. Justification Book Volume 2a of 5, p. 10569, at https://comptroller.defense.gov/Portals/45/Documents/defbudget/, at https://comptroller.defense.gov/Portals/45/Documents/defbudget/~~fy2021~~fy2022//
budget_justification/pdfs/03_RDT_and_E/budget_justification/pdfs/03_RDT_and_E/~~RDTE_Vol2_MDA_RDTE_PB21_Justification_Book.pdf.~~
~~124~~RDTE_Vol2_MDA_RDTE_PB22_Justification_Book.pdf; and Defense Budget Overview: United States Department of Defense Fiscal Year 2022 Budget Request, Office of the Under Secretary of Defense (Comptroller)/Chief Financial Officer, May 2021, p. 3-2, at https://comptroller.defense.gov/Portals/45/Documents/defbudget/FY2022/FY2022_Budget_Request_Overview_Book.pdf. 133 “Department of Defense Appropriations Act, 2020: Joint Explanatory Statement,” Defense Subcommittees of the “Department of Defense Appropriations Act, 2020: Joint Explanatory Statement,” Defense Subcommittees of the
Appropriations Committees, December 16, 2019, at https://appropriations.house.gov/sites/Appropriations Committees, December 16, 2019, at https://appropriations.house.gov/sites/
democrats.appropriations.house.gov/files/HR%201158%20-%20Division%20A%20-democrats.appropriations.house.gov/files/HR%201158%20-%20Division%20A%20-
%20Defense%20SOM%20FY20.pdf. %20Defense%20SOM%20FY20.pdf.
~~125~~134 Ibid. The Joint Hypersonic Transition Office, then called the Joint Technology Office on Hypersonics, was Ibid. The Joint Hypersonic Transition Office, then called the Joint Technology Office on Hypersonics, was
originally mandated by Section 218 of the FY2007 NDAA (P.L. 109-364). The office was redesignated as the Joint originally mandated by Section 218 of the FY2007 NDAA (P.L. 109-364). The office was redesignated as the Joint
Hypersonics Transition Office and given additional authorities in Section 214 of the FY2018 NDAA (P.L. 115-91). Hypersonics Transition Office and given additional authorities in Section 214 of the FY2018 NDAA (P.L. 115-91).
Section 216 of the FY2020 NDAA (P.L. 116-92) further amended the office’s authorities to include the ability to enter Section 216 of the FY2020 NDAA (P.L. 116-92) further amended the office’s authorities to include the ability to enter
into agreements with institutions of higher learning. The office went unfunded until FY2020 and was not established into agreements with institutions of higher learning. The office went unfunded until FY2020 and was not established
until April 2020. until April 2020.
~~126 David Vergun, “DOD Awards Applied Hypersonics Contract to Texas A&M University,” DOD News, October 26,~~
~~2020, at https://www.defense.gov/Explore/News/Article/Article/2394438/dod-awards-applied-hypersonics-contract-to-~~
~~texas-am-university/.~~
~~127 Ibid.~~
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Congressional Research Service 22 Hypersonic Weapons: Background and Issues for Congress DOD established the JHTO in April 2020 and announced on October 26, 2020, that it awarded Texas A&M University with a $20 million contract—renewable for up to $100 million—to manage a University Consortium for Applied Hypersonics (UCAH).135 UCAH is to be overseen by a group of academic researchers from Texas A&M University, the Massachusetts Institute of Technology, the University of Minnesota, the University of Illinois at Urbana-Champaign, the University of Arizona, the University of Tennessee Space Institute, Morgan State University, the California Institute of Technology, Purdue University, the University of California-Los Angeles, and the Georgia Institute of Technology.136 The consortium is to “facilitate transitioning academic research into developing systems [as well as] work with the department to reduce system research into developing systems [as well as] work with the department to reduce system
development timelines while maintaining quality control standards.”development timelines while maintaining quality control standards.”~~128~~137
In addition, Section 1671 of the FY2021 NDAA (P.L. 116-283) directs the Secretary of the Army In addition, Section 1671 of the FY2021 NDAA (P.L. 116-283) directs the Secretary of the Army
and the Secretary of the Navy to jointly submit to the congressional defense committees a report and the Secretary of the Navy to jointly submit to the congressional defense committees a report
on LRHW and CPS, including total costs of the programs, “the strategy for such programs with on LRHW and CPS, including total costs of the programs, “the strategy for such programs with
respect to manning, training, and equipping, including cost estimates, [and] a testing strategy and respect to manning, training, and equipping, including cost estimates, [and] a testing strategy and
schedule for such programs.” It directs the Director of Cost Assessment and Program Evaluation schedule for such programs.” It directs the Director of Cost Assessment and Program Evaluation
to submit to the congressional defense committees an independent cost estimate of these to submit to the congressional defense committees an independent cost estimate of these
programs.programs.~~129~~138
Given the lack of defined mission requirements for hypersonic weapons, however, it may be Given the lack of defined mission requirements for hypersonic weapons, however, it may be
challenging for Congress to evaluate the balance of funding for hypersonic weapons programs, challenging for Congress to evaluate the balance of funding for hypersonic weapons programs,
enabling technologies, supporting test infrastructure, and hypersonic missile defense. enabling technologies, supporting test infrastructure, and hypersonic missile defense.
Strategic Stability
Analysts disagree about the strategic implications of hypersonic weapons. Some have identified Analysts disagree about the strategic implications of hypersonic weapons. Some have identified
two factors that could hold significant implications for strategic stability: the weapon’s short two factors that could hold significant implications for strategic stability: the weapon’s short
time-of-flight—which, in turn, compresses the timeline for response—and its unpredictable flight time-of-flight—which, in turn, compresses the timeline for response—and its unpredictable flight
path—which could generate uncertainty about the weapon’s intended target and therefore path—which could generate uncertainty about the weapon’s intended target and therefore
heighten the risk of miscalculation or unintended escalation in the event of a conflict. This risk heighten the risk of miscalculation or unintended escalation in the event of a conflict. This risk
could be further compounded in countries that co-locate nuclear and conventional capabilities or could be further compounded in countries that co-locate nuclear and conventional capabilities or
facilities. facilities.
Some analysts argue that unintended escalation could occur as a result of warhead ambiguity, or Some analysts argue that unintended escalation could occur as a result of warhead ambiguity, or
from the inability to distinguish between a conventionally armed hypersonic weapon and a from the inability to distinguish between a conventionally armed hypersonic weapon and a
nuclear-armed one. However, as a United Nations report notes, “even if a State did know that an nuclear-armed one. However, as a United Nations report notes, “even if a State did know that an
HGV launched toward it was conventionally armed, it may still view such a weapon as strategic HGV launched toward it was conventionally armed, it may still view such a weapon as strategic
in nature, regardless of how it was perceived by the State firing the weapon, and decide that a in nature, regardless of how it was perceived by the State firing the weapon, and decide that a
strategic response was warranted.”strategic response was warranted.”~~130~~139 Differences in threat perception and escalation ladders 135 David Vergun, “DOD Awards Applied Hypersonics Contract to Texas A&M University,” DOD News, October 26, 2020, at https://www.defense.gov/Explore/News/Article/Article/2394438/dod-awards-applied-hypersonics-contract-to-texas-am-university/. 136 Ibid. 137 Ibid. 138 ~~Differences in threat perception and escalation ladders~~
~~could thus result in unintended escalation. Such concerns have previously led Congress to restrict~~
~~funding for conventional prompt strike programs.131~~
~~Other analysts have argued that the strategic implications of hypersonic weapons are minimal.~~
~~Pavel Podvig, a senior research fellow at the United Nations Institute for Disarmament Research,~~
~~has noted that the weapons “don’t … change much in terms of strategic balance and military~~
~~capability.”132 This, some analysts argue, is because U.S. competitors such as China and Russia~~
~~already possess the ability to strike the United States with intercontinental ballistic missiles,~~

~~128 Ibid.~~
~~129~~ The Government Accountability Office notes DOD’s difficulty in developing accurate cost estimates for hypersonic The Government Accountability Office notes DOD’s difficulty in developing accurate cost estimates for hypersonic
weapons programs. For example, between FY2019 and FY2020, estimates for CPS “almost doubled.” Government weapons programs. For example, between FY2019 and FY2020, estimates for CPS “almost doubled.” Government
Accountability Office, Accountability Office, Hypersonic Weapons: DOD Should Clarify Roles and Responsibilities to Ensure Coordination
across Development Efforts, GAO-21-378, March 22, 2021, p. 21, at https://www.gao.gov/products/gao-21-378. , GAO-21-378, March 22, 2021, p. 21, at https://www.gao.gov/products/gao-21-378.
~~130~~139 United Nations Office of Disarmament Affairs, United Nations Office of Disarmament Affairs, Hypersonic Weapons.
~~131 For a history of legislative activity on conventional prompt global strike, see CRS Report R41464,~~ ~~Conventional~~
~~Prompt Global Strike and Long-Range Ballistic Missiles: Background and Issues, by Amy F. Woolf.~~
~~132 Amy Mackinnon, “Russia’s New Missiles Are Aimed at the U.S.,” Foreign Policy, March 5, 2019, at~~
~~https://foreignpolicy.com/2019/03/05/russias-new-missiles-are-aimed-at-you-weapons-hypersonic-putin-united-states-~~
~~inf/.~~
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~~Hypersonic Weapons: Background and Issues for Congress~~

~~which, when launched in salvos, could overwhelm U.S. missile defenses.133~~ Congressional Research Service 23 Hypersonic Weapons: Background and Issues for Congress could thus result in unintended escalation. Such concerns have previously led Congress to restrict funding for conventional prompt strike programs.140 Other analysts have argued that the strategic implications of hypersonic weapons are minimal. Pavel Podvig, a senior research fellow at the United Nations Institute for Disarmament Research, has noted that the weapons “don’t … change much in terms of strategic balance and military capability.”141 This, some analysts argue, is because U.S. competitors such as China and Russia already possess the ability to strike the United States with intercontinental ballistic missiles, which, when launched in salvos, could overwhelm U.S. missile defenses.142 Furthermore, these Furthermore, these
analysts note that in the case of hypersonic weapons, traditional principles of deterrence hold: “it analysts note that in the case of hypersonic weapons, traditional principles of deterrence hold: “it
is really a stretch to try to imagine any regime in the world that would be so suicidal that it would is really a stretch to try to imagine any regime in the world that would be so suicidal that it would
even think threating to use—not to mention to actually use—hypersonic weapons against the even think threating to use—not to mention to actually use—hypersonic weapons against the
United States ... would end well.”United States ... would end well.”~~134~~143
Section 1671 of the FY2021 NDAA (P.L. 116-283) directs the Chairman of the Joint Chiefs of Section 1671 of the FY2021 NDAA (P.L. 116-283) directs the Chairman of the Joint Chiefs of
Staff, in coordination with the Under Secretary of Defense for Policy, to submit to the Staff, in coordination with the Under Secretary of Defense for Policy, to submit to the
congressional defense committees a report that examines congressional defense committees a report that examines
How escalation risks will be addressed with regards to the use of strategic hypersonic How escalation risks will be addressed with regards to the use of strategic hypersonic
weapons, including whether any risk escalation exercises have been conducted or are weapons, including whether any risk escalation exercises have been conducted or are
planned for the potential use of hypersonic weapons, and an analysis of the escalation risks planned for the potential use of hypersonic weapons, and an analysis of the escalation risks
posed by foreign hypersonic systems that are potentially nuclear and conventional dual-posed by foreign hypersonic systems that are potentially nuclear and conventional dual-
use capable weapons. use capable weapons.
Arms Control
Some analysts who believe that hypersonic weapons could present a threat to strategic stability or Some analysts who believe that hypersonic weapons could present a threat to strategic stability or
inspire an arms race have argued that the United States should take measures to mitigate risks or inspire an arms race have argued that the United States should take measures to mitigate risks or
limit the weapons’ proliferation. Proposed measures include expanding New START, negotiating limit the weapons’ proliferation. Proposed measures include expanding New START, negotiating
new multilateral arms control agreements, and undertaking transparency and confidence-building new multilateral arms control agreements, and undertaking transparency and confidence-building
measures.measures.~~135~~144
The New START Treaty, a strategic offensive arms treaty between the United States and Russia, The New START Treaty, a strategic offensive arms treaty between the United States and Russia,
does not currently cover weapons that fly on a ballistic trajectory for less than 50% of their flight, does not currently cover weapons that fly on a ballistic trajectory for less than 50% of their flight,
as do hypersonic glide vehicles and hypersonic cruise missiles.as do hypersonic glide vehicles and hypersonic cruise missiles.~~136~~145 However, Article V of the treaty However, Article V of the treaty
states that “when a Party believes that a new kind of strategic offensive arm is emerging, that states that “when a Party believes that a new kind of strategic offensive arm is emerging, that
Party shall have the right to raise the question of such a strategic offensive arm for consideration Party shall have the right to raise the question of such a strategic offensive arm for consideration
~~in the Bilateral Consultative Commission (BCC).” Accordingly, some legal experts hold that the~~
~~United States could raise the issue in the BCC of negotiating to include hypersonic weapons in~~
~~the New START limits.137 However, because New START is due to expire in 2026, this may be a~~
~~short-term solution.138~~
~~As an alternative, some analysts have proposed negotiating a new international arms control~~
~~agreement that would institute a moratorium or ban on hypersonic weapon testing. These analysts~~

~~133~~ 140 For a history of legislative activity on conventional prompt global strike, see CRS Report R41464, Conventional Prompt Global Strike and Long-Range Ballistic Missiles: Background and Issues, by Amy F. Woolf. 141 Amy Mackinnon, “Russia’s New Missiles Are Aimed at the U.S.,” Foreign Policy, March 5, 2019, at https://foreignpolicy.com/2019/03/05/russias-new-missiles-are-aimed-at-you-weapons-hypersonic-putin-united-states-inf/. 142 David Axe, “How the U.S. Is Quietly Winning the Hypersonic Arms Race,” David Axe, “How the U.S. Is Quietly Winning the Hypersonic Arms Race,” The Daily Beast, January 16, 2019, at , January 16, 2019, at
https://www.thedailybeast.com/how-the-us-is-quietly-winning-the-hypersonic-arms-race. See also Mark B. Schneider, https://www.thedailybeast.com/how-the-us-is-quietly-winning-the-hypersonic-arms-race. See also Mark B. Schneider,
“Moscow’s Development of Hypersonic Missiles,” p. 14. “Moscow’s Development of Hypersonic Missiles,” p. 14.
~~134~~143 Jyri Raitasalo, “Hypersonic Weapons are No Game-Changer,” Jyri Raitasalo, “Hypersonic Weapons are No Game-Changer,” The National Interest, January 5, 2019, at , January 5, 2019, at
https://nationalinterest.org/blog/buzz/hypersonic-weapons-are-no-game-changer-40632. https://nationalinterest.org/blog/buzz/hypersonic-weapons-are-no-game-changer-40632.
~~135~~144 See United Nations Office of Disarmament Affairs, See United Nations Office of Disarmament Affairs, Hypersonic Weapon; and; and Richard H. Speier et al., Richard H. Speier et al., Hypersonic
Missile Proliferation.
~~136~~145 In some cases, hypersonic glide vehicles may be launched from intercontinental ballistic missiles that are already In some cases, hypersonic glide vehicles may be launched from intercontinental ballistic missiles that are already
covered by New START, as is reported to be the case with Russia’s Avangard HGV. See Rachel S. Cohen, covered by New START, as is reported to be the case with Russia’s Avangard HGV. See Rachel S. Cohen,
“Hypersonic Weapons: Strategic Asset or Tactical Tool?” “Hypersonic Weapons: Strategic Asset or Tactical Tool?”
~~137 James Acton notes: “during [New START] negotiations, Russia argued that boost-glide weapons might constitute ‘a~~
~~new kind of strategic offensive arm,’ in which case they would trigger bilateral discussions about whether and how~~
~~they would be regulated by the treaty—a position [then] rejected by the United States.” James M. Acton,~~ ~~Silver Bullet?:~~
~~Asking the Right Questions about Conventional Prompt Global Strike, Carnegie Endowment for International Peace,~~
~~2013, p. 139, at https://carnegieendowment.org/files/cpgs.pdf.~~
~~138 CRS Report R41219, The New START Treaty: Central Limits and Key Provisions, by Amy F. Woolf.~~
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Congressional Research Service 24 Hypersonic Weapons: Background and Issues for Congress in the Bilateral Consultative Commission (BCC).” Accordingly, some legal experts hold that the United States could raise the issue in the BCC of negotiating to include hypersonic weapons in the New START limits.146 However, because New START is due to expire in 2026, this may be a short-term solution.147 As an alternative, some analysts have proposed negotiating a new international arms control agreement that would institute a moratorium or ban on hypersonic weapon testing. These analysts argue that a test ban would be a “highly verifiable” and “highly effective” means of preventing a argue that a test ban would be a “highly verifiable” and “highly effective” means of preventing a
potential arms race and preserving strategic stability.potential arms race and preserving strategic stability.~~139~~148 Other analysts have countered that a test Other analysts have countered that a test
ban would be infeasible, as “no clear technical distinction can be made between hypersonic ban would be infeasible, as “no clear technical distinction can be made between hypersonic
missiles and other conventional capabilities that are less prompt, have shorter ranges, and also missiles and other conventional capabilities that are less prompt, have shorter ranges, and also
have the potential to undermine nuclear deterrence.”have the potential to undermine nuclear deterrence.”~~140~~149 These analysts have instead proposed These analysts have instead proposed
international transparency and confidence-building measures, such as exchanging weapons data; international transparency and confidence-building measures, such as exchanging weapons data;
conducting joint technical studies; “providing advance notices of tests; choosing separate, conducting joint technical studies; “providing advance notices of tests; choosing separate,
distinctive launch locations for tests of hypersonic missiles; and placing restraints on sea-based distinctive launch locations for tests of hypersonic missiles; and placing restraints on sea-based
tests.”tests.”~~141~~150

~~139~~146 James Acton notes: “during [New START] negotiations, Russia argued that boost-glide weapons might constitute ‘a new kind of strategic offensive arm,’ in which case they would trigger bilateral discussions about whether and how they would be regulated by the treaty—a position [then] rejected by the United States.” James M. Acton, Silver Bullet?: Asking the Right Questions about Conventional Prompt Global Strike, Carnegie Endowment for International Peace, 2013, p. 139, at https://carnegieendowment.org/files/cpgs.pdf. 147 CRS Report R41219, The New START Treaty: Central Limits and Key Provisions, by Amy F. Woolf. 148 Mark Gubrud, “Test Ban for Hypersonic Missiles?” Bulletin of the Atomic Scientists, August 6, 2015, at Mark Gubrud, “Test Ban for Hypersonic Missiles?” Bulletin of the Atomic Scientists, August 6, 2015, at
https://thebulletin.org/roundtable/test-ban-for-hypersonic-missiles/. https://thebulletin.org/roundtable/test-ban-for-hypersonic-missiles/.
~~140~~149 Tong Zhao, “Test Ban for Hypersonic Missiles?” Tong Zhao, “Test Ban for Hypersonic Missiles?”
~~141~~150 Rajaram Nagappa, “Test Ban for Hypersonic Missiles?”; see also James M. Acton, Rajaram Nagappa, “Test Ban for Hypersonic Missiles?”; see also James M. Acton, Silver Bullet?, pp. 134-138. , pp. 134-138.
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Appendix. U.S. Hypersonic Testing ~~Infrastructure142~~Infrastructure151
Table A-1. DOD Hypersonic Ground Test Facilities
Facility
Capability
Location
Air Force Arnold Engineering and Air Force Arnold Engineering and
Tunnel A: 40-inch Mach 1.5-5.5; up Tunnel A: 40-inch Mach 1.5-5.5; up
Arnold AFB, TN Arnold AFB, TN
Development Complex (AEDC) von Development Complex (AEDC) von
to 290 °F to 290 °F
Karman Gas Dynamics Facility Karman Gas Dynamics Facility
Tunnel B: 50-inch Mach 6 and 8; up Tunnel B: 50-inch Mach 6 and 8; up
Tunnels A/B/C Tunnels A/B/C
to 900 °F to 900 °F
Tunnel C: 50-inch Mach 10; up to Tunnel C: 50-inch Mach 10; up to
1700 °F 1700 °F
Air Force AEDC High-Enthalpy Air Force AEDC High-Enthalpy
Simulate thermal and pressure Simulate thermal and pressure
Arnold AFB, TN Arnold AFB, TN
Aerothermal Test Arc-Heated Aerothermal Test Arc-Heated
environments at speeds of up to environments at speeds of up to
Facilities H1, H2, H3 Facilities H1, H2, H3
Mach 8 Mach 8
Air Force AEDC Tunnel 9 Air Force AEDC Tunnel 9
59-inch Mach 7, 8,10, 14, and18; up White Oak, MD 59-inch Mach 7, 8,10, 14, and18; up White Oak, MD
to 2900 °F to 2900 °F
Air Force AEDC Aerodynamic and Air Force AEDC Aerodynamic and
Mach 3.1-7.2; up to 1300 °F Mach 3.1-7.2; up to 1300 °F
Arnold AFB, TN Arnold AFB, TN
Propulsion Test Unit Propulsion Test Unit
Air Force AEDC Aeroballistic Range Air Force AEDC Aeroballistic Range
Launches projectiles of up to 8 Launches projectiles of up to 8
Arnold AFB, TN Arnold AFB, TN
G G
inches in diameter at speeds of up inches in diameter at speeds of up
to Mach 20 to Mach 20
Hol oman High Speed Test Track Hol oman High Speed Test Track
59,971 ft. track; launches 59,971 ft. track; launches
Hol oman AFB, NM Hol oman AFB, NM
projectiles at speeds of up to Mach projectiles at speeds of up to Mach
8 8
Air Force Research Laboratory Air Force Research Laboratory
Mach 3-7 Mach 3-7
Wright-Patterson AFB, OH Wright-Patterson AFB, OH
(AFRL) Cells 18, 22 (AFRL) Cells 18, 22
AFRL Laser Hardened Materials AFRL Laser Hardened Materials
High-temperature materials testing High-temperature materials testing
Wright-Patterson AFB, OH Wright-Patterson AFB, OH
Evaluation Laboratory (LHMEL) Evaluation Laboratory (LHMEL)
AFRL Mach 6 High Reynolds AFRL Mach 6 High Reynolds
10-inch Mach 6 10-inch Mach 6
Wright-Patterson AFB, OH Wright-Patterson AFB, OH
Number (Re) Facility Number (Re) Facility
Test Resource Management Center Test Resource Management Center
Up to Mach 8; up to 4040 °F Up to Mach 8; up to 4040 °F
Arnold AFB, TN Arnold AFB, TN
Hypersonic Aeropropulsion Clean Hypersonic Aeropropulsion Clean
Air Test-bed Facility Air Test-bed Facility
Source: (U//FOUO) Paul F. Piscopo et al. Air Force AEDC Tunnel 9 was upgraded in 2019 to enable Mach 18 (U//FOUO) Paul F. Piscopo et al. Air Force AEDC Tunnel 9 was upgraded in 2019 to enable Mach 18
testing. See “Department of Defense Press Briefing on Hypersonics,” March 2, 2020, at https://www.defense.gov/testing. See “Department of Defense Press Briefing on Hypersonics,” March 2, 2020, at https://www.defense.gov/
Newsroom/Transcripts/Transcript/Article/2101062/department-of-defense-press-briefing-on-hypersonics/. Newsroom/Transcripts/Transcript/Article/2101062/department-of-defense-press-briefing-on-hypersonics/.

~~142~~151 The following information is derived from the 2014 report (U//FOUO) Paul F. Piscopo et al., The following information is derived from the 2014 report (U//FOUO) Paul F. Piscopo et al., (U) Study on the
Ability of the U.S. Test and Evaluation Infrastructure, and therefore, may not be current. Permission to use this material , and therefore, may not be current. Permission to use this material
has been granted by the Office of Science and Technology Policy. has been granted by the Office of Science and Technology Policy.
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Table A-2. DOD Open-Air Ranges
Range
Location
Ronald Reagan Ballistic Missile Ronald Reagan Ballistic Missile
Kwajalein Atol , Republic of the Kwajalein Atol , Republic of the
Defense Test Site Defense Test Site
Marshall Islands Marshall Islands
Pacific Missile Range Facility (PMRF) Pacific Missile Range Facility (PMRF)
Kauai, HI Kauai, HI
Western Range, 30th Space Wing Western Range, 30th Space Wing
Vandenberg AFB, CA Vandenberg AFB, CA
Naval Air Warfare Center Weapons Naval Air Warfare Center Weapons
Point Mugu and China Lake, CA Point Mugu and China Lake, CA
(NAWC) Division (NAWC) Division
White Sands Missile Range (WSMR) White Sands Missile Range (WSMR)
New Mexico New Mexico
Eastern Range, 45th Space Wing Eastern Range, 45th Space Wing
Cape Canaveral Air Force Cape Canaveral Air Force
Station/Patrick AFB/Kennedy Station/Patrick AFB/Kennedy
Space Center, FL Space Center, FL
NASA Wallops Flight Facility NASA Wallops Flight Facility
Wallops Island, VA Wallops Island, VA
Pacific Spaceport Complex (formerly Pacific Spaceport Complex (formerly
Kodiak Island, AK Kodiak Island, AK
Kodiak Launch Complex) Kodiak Launch Complex)
NAWC Weapons Division R-2508 NAWC Weapons Division R-2508
Edwards AFB, CA Edwards AFB, CA
Complex Complex
Utah Test and Training Range Utah Test and Training Range
Utah Utah
Nevada Test and Training Range Nevada Test and Training Range
Nevada Nevada
Source: (U//FOUO) Paul F. Piscopo et al. (U//FOUO) Paul F. Piscopo et al.
Table A-3. DOD Mobile Assets
Asset
Navy Mobile Instrumentation Navy Mobile Instrumentation
System System
PMRF Mobile At-sea Sensor System PMRF Mobile At-sea Sensor System
MDA Mobile Instrumentation MDA Mobile Instrumentation
System System Pacific Collector
MDA Mobile Instrumentation MDA Mobile Instrumentation
System System Pacific Tracker
Kwajalein Mobile Range Safety Kwajalein Mobile Range Safety
System 2 System 2
United States Navy Ship United States Navy Ship Lorenzen
missile range instrumentation ship missile range instrumentation ship
Sea-based X-band Radar Sea-based X-band Radar
Aircraft Mobile Instrumentation Aircraft Mobile Instrumentation
Systems Systems
Transportable Range Augmentation Transportable Range Augmentation
and Control System and Control System
Re-locatable MPS-36 Radar Re-locatable MPS-36 Radar
Transportable Telemetry System Transportable Telemetry System
Source: (U//FOUO) Paul F. Piscopo et al. (U//FOUO) Paul F. Piscopo et al.
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Table A-4. NASA Research-Related Facilities
Facility
Capability
Location
Ames Research Center (ARC) High-temperature Ames Research Center (ARC) High-temperature
Mountain View, CA Mountain View, CA
Arc Jet Complex Arc Jet Complex
materials testing materials testing
ARC Hypervelocity Free ARC Hypervelocity Free
Launches projectiles at Launches projectiles at
Mountain View, CA Mountain View, CA
Flight Facilities Flight Facilities
speeds of up to Mach 23 speeds of up to Mach 23
Langley Research Center Langley Research Center
31-inch Mach 10, 20-inch 31-inch Mach 10, 20-inch
Hampton, VA Hampton, VA
(LaRC) Aerothermodynamics (LaRC) Aerothermodynamics
Mach 6, and 15-inch Mach Mach 6, and 15-inch Mach
Laboratory Laboratory
6 6
LaRC 8-foot High LaRC 8-foot High
96-inch Mach 5 and Mach 96-inch Mach 5 and Mach
Hampton, VA Hampton, VA
Temperature Tunnel Temperature Tunnel
6.5 6.5
LaRC Scramjet Test Complex LaRC Scramjet Test Complex
Up to Mach 8 and up to Up to Mach 8 and up to
Hampton, VA Hampton, VA
4740 °F 4740 °F
LaRC HyPulse Facility LaRC HyPulse Facility
Currently inactive Currently inactive
Long Island, NY Long Island, NY
Glenn Research Center Glenn Research Center
Mach 5, 6, and 7 and up to Sandusky, OH Mach 5, 6, and 7 and up to Sandusky, OH
(GRC) Plumbrook Hypersonic 3830 °F (GRC) Plumbrook Hypersonic 3830 °F
Tunnel Facility Arc Jet Facility Tunnel Facility Arc Jet Facility
GRC Propulsion Systems GRC Propulsion Systems
Mach 6 Mach 6
Cleveland, OH Cleveland, OH
Laboratory 4 Laboratory 4
GRC 1’ x 1’ Supersonic Wind GRC 1’ x 1’ Supersonic Wind
12-inch Mach 1.3-6 (10 12-inch Mach 1.3-6 (10
Cleveland, OH Cleveland, OH
Tunnel Tunnel
discrete airspeeds) and up discrete airspeeds) and up
to 640 °F to 640 °F
Source: (U//FOUO) Paul F. Piscopo et al. (U//FOUO) Paul F. Piscopo et al.
Table A-5. Department of Energy Research-Related Facilities
Facility
Capability
Location
Sandia National Laboratories Solar Sandia National Laboratories Solar
High-temperature materials testing High-temperature materials testing
Albuquerque, NM Albuquerque, NM
Thermal Test Facility Thermal Test Facility
and aerodynamic heating simulation and aerodynamic heating simulation
Sandia National Laboratories Sandia National Laboratories
18-inch Mach 5, 8, and 14 18-inch Mach 5, 8, and 14
Albuquerque, NM Albuquerque, NM
Hypersonic Wind Tunnel Hypersonic Wind Tunnel
Source: (U//FOUO) Paul F. Piscopo et al. (U//FOUO) Paul F. Piscopo et al.
Table A-6. Industry/Academic Research-Related Facilities
Facility
Capability
Location
CUBRC Large Energy National CUBRC Large Energy National
LENS 1: Mach 6-22 LENS 1: Mach 6-22
Buffalo, NY Buffalo, NY
Shock (LENS)-1/-II/-XX Tunnels Shock (LENS)-1/-II/-XX Tunnels
LENS II: Mach 2-12 LENS II: Mach 2-12
LENS XX: Atmospheric reentry LENS XX: Atmospheric reentry
simulation simulation
Boeing Polysonic Wind Tunnel Boeing Polysonic Wind Tunnel
48-inch up to Mach 5 48-inch up to Mach 5
St. Louis, MO St. Louis, MO
Lockheed Martin High Speed Wind Lockheed Martin High Speed Wind
48-inch Mach .3-5 48-inch Mach .3-5
Dallas, TX Dallas, TX
Tunnel Tunnel
Boeing/Air Force Office of Scientific 9.5-inch Mach 6 Boeing/Air Force Office of Scientific 9.5-inch Mach 6
West Lafayette, IN West Lafayette, IN
Research (AFOSR) Quiet Tunnel at Research (AFOSR) Quiet Tunnel at
Purdue University Purdue University
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AFOSR-University of Notre Dame AFOSR-University of Notre Dame
24-inch Mach 6 24-inch Mach 6
Notre Dame, IN Notre Dame, IN
Quiet Tunnel Quiet Tunnel
Stratolaunch Carrier Aircraft Stratolaunch Carrier Aircraft
Reusable Mach 6 test bed Reusable Mach 6 test bed
N/A N/A
Sources: (U//FOUO) Paul F. Piscopo et al.; Oriana Pawlyk, “Air Force Expanding Hypersonic Technology (U//FOUO) Paul F. Piscopo et al.; Oriana Pawlyk, “Air Force Expanding Hypersonic Technology
Testing”; University of Arizona, “Mach 5 Quiet Ludwieg Tube”; and Ashley Tressel, “Army to open hypersonic Testing”; University of Arizona, “Mach 5 Quiet Ludwieg Tube”; and Ashley Tressel, “Army to open hypersonic
testing facility.” testing facility.”
Notes: Hypersonic wind tunnels are under construction at the fol owing universities: Texas A&M University Hypersonic wind tunnels are under construction at the fol owing universities: Texas A&M University
(Mach 10 quiet tunnel), the University of Arizona (Mach 5 quiet tunnel), Purdue University (Mach 8 quiet tunnel), (Mach 10 quiet tunnel), the University of Arizona (Mach 5 quiet tunnel), Purdue University (Mach 8 quiet tunnel),
and the University of Notre Dame (Mach 10 quiet tunnel). Additional universities, such as the University of and the University of Notre Dame (Mach 10 quiet tunnel). Additional universities, such as the University of
Maryland, the California Institute of Technology, the Georgia Institute of Technology, the Air Force Academy, Maryland, the California Institute of Technology, the Georgia Institute of Technology, the Air Force Academy,
the University of Tennessee Space Institute, and Virginia Polytechnic Institute and State University, also maintain the University of Tennessee Space Institute, and Virginia Polytechnic Institute and State University, also maintain
experimental hypersonic facilities or conduct hypersonic research. experimental hypersonic facilities or conduct hypersonic research.

Author Information

Kelley M. Sayler Kelley M. Sayler

Analyst in Advanced Technology and Global Analyst in Advanced Technology and Global
Security Security

Disclaimer
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