Hypersonic Weapons: Background and Issues for Congress

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Hypersonic Weapons: ~~Background and Issues~~
~~April 26, 2021~~
July 9, 2021 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—
Analyst in Advanced Analyst in Advanced
maneuvering weapons that fly at speeds of at least Mach 5—as a part of its conventional maneuvering weapons that fly at speeds of at least Mach 5—as a part of its conventional
Technology and Global Technology and Global
prompt global strike program since the early 2000s. In recent years, the United States prompt global strike program since the early 2000s. In recent years, the United States
Security Security
has focused such efforts on developing hypersonic glide vehicles, which are launched has focused such efforts on developing hypersonic glide vehicles, which are launched

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

powered by high-speed, air-breathing engines during flight. As Vice Chairman of the powered by high-speed, air-breathing engines during flight. As Vice Chairman of the
Joint Chiefs of Staff and former Commander of U.S. Strategic Command General John Hyten has stated, these Joint Chiefs of Staff and former Commander of 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 systems. This is due, in part, to the ~~growing interest~~advances in these technologies in Russia and China, both of which have in these technologies in Russia and China, both of which have
a 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~~potential y armed with nuclear warheads. Most U.S. hypersonic weapons, in contrast to those in Russia and 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 China, are not being designed for use with a nuclear warhead. As a result, U.S. hypersonic weapons ~~will~~ wil likely likely
require greater accuracy and require greater accuracy and ~~will be more technically challenging~~wil be more technical y chal enging to develop than nuclear-armed Chinese and to develop than nuclear-armed Chinese and
Russian systems. Russian systems.
The Pentagon’s The Pentagon’s ~~FY2021~~FY2022 budget request for budget request for ~~all hypersonic-related~~hypersonic research is $3. research is $3.~~2 billion~~8 bil ion—up from $—up from $~~2.6 billion~~3.2 bil ion in in
~~the FY2020 request—including $206.8 million~~the FY2021 request. The Missile Defense Agency additional y requested $247.9 mil ion for hypersonic defense for hypersonic defense ~~programs~~. At present, the Department of . At present, the Department of
Defense (DOD) has not established any programs of record for hypersonic weapons, Defense (DOD) has not established any programs of record for hypersonic weapons, suggesting that it may not suggesting that it may not
have approved either have approved either mission requirements for the systems or long-term funding plans. Indeed, as requirements for the systems or long-term funding plans. Indeed, as ~~Assistant~~Principal Director for Director for
Hypersonics (Office of the Under Secretary of Defense for Research and Engineering) Mike White has stated, 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 instead developing prototypes to assist in 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. 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)  What mission(s) ~~will~~ wil hypersonic weapons be used for? Are hypersonic weapons the most cost-hypersonic weapons be used for? Are hypersonic weapons the most cost-
effective means of executing these potential missions? How effective means of executing these potential missions? How ~~will~~ wil they be incorporated into joint 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 funding requests for hypersonic weapons programs or the balance of funding requests evaluate 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 defense options both necessary and ~~technologically~~technological y feasible? feasible?
 How, if at  How, if at ~~all, will~~ al , wil the fielding of hypersonic weapons affect strategic stability? 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 to ~~the growing interest~~advances in these technologies in Russia and China, leading to a heightened focus in 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 the 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 indicates that both China and Russia have conducted numerous successful tests of hypersonic
glide glide vehicles and likelyvehicles and likely fielded an operational capability. 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,S. McCain National Defense Authorization Act for Fiscal Year 2019 (FY2019 NDAA, P.L. 115-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 hypersonic weapons ~~will likely~~ wil likely require greater accuracy and require greater accuracy and ~~will be more technically challenging~~
wil be more technical y chal enging 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~~Intel igence Agency, produce a classified assessment of U.S. and adversary hypersonic weapons 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) (4) An assessment of the technological progress of the United States and adversaries on 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 CRS1 For details, see CRS Report R41464, 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.2 U.S. Congress, Senate Committee on Armed Services,Congress, Senate Committee on Armed Services, ~~“Testimony~~ “T estimony of Michael Griffin,” Hearing on New of Michael Griffin,” Hearing on New
~~Technologies~~T echnologies to Meet Emerging to Meet Emerging ~~Threats~~T hreats, April 18, 2018, https://www.armed-services.senate.gov/imo/media/doc/18-, April 18, 2018, 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 3 Until recently, the United States was not believed to be considering the development of nuclear-armed hypersonic not believed to be considering the development of nuclear-armed hypersonic
weapons; however, a since-revoked Air Force solicitation sought ideas for a “weapons; however, a since-revoked Air Force solicitation sought ideas for a “ thermal protection system that can thermal protection system that can
support [a] hypersonic glide to ICBM ranges.” Seniorsupport [a] hypersonic glide to ICBM ranges.” Senior defense officials respondeddefense officials responded to news reports of the revocation, to news reports of the revocation,
stating that DOD “remains stating that DOD “remains ~~committed~~committ ed to non-nuclear role for hypersonics.” See Steve to non-nuclear role for hypersonics.” See Steve ~~Trimble~~T rimble, “USAF Errantly , “USAF Errantly
Reveals Research on ICBM-RangeReveals Research on ICBM-Range Hypersonic GlideHypersonic Glide Vehicle,”Vehicle,” Aviation Week, August 18, 2020, Aviation Week, August 18, 2020,
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 Unlike ~~ballistic~~ bal istic missiles, hypersonic weapons do not follow a missiles, hypersonic weapons do not follow a ~~ballistic~~bal istic trajectory and can trajectory and can
maneuver en route to their destination. As Vice Chairman of the Joint Chiefs of Staff and former maneuver en route to their destination. As Vice Chairman of the Joint Chiefs of Staff and former
Commander of U.S. Strategic Command General John Hyten has stated, hypersonic weapons 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 time-critical 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 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 derived from preferred.”8 Conventional hypersonic weapons use only kinetic energy—energy derived from
motion—to destroy unhardened targets or, motion—to destroy unhardened targets or, ~~potentially~~potential y, underground facilities.9, underground facilities.9
Hypersonic weapons could Hypersonic weapons could ~~challenge~~chal enge detection and defense due to their speed, maneuverability, 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.weapons until late in the weapon’s flight.1111 Figure 1 depicts the differences in terrestrial-based depicts the differences in terrestrial-based
radar detection timelines for radar detection timelines for ~~ballistic~~bal istic missiles versus hypersonic glide vehicles. missiles versus hypersonic glide vehicles.

4 P.L. 115-232, Section 2, Division A, 4 P.L. 115-232, Section 2, Division A, ~~Title~~T itle II, §247. II, §247.
5 P.L. 115-232, Section 2, Division A, 5 P.L. 115-232, Section 2, Division A, ~~Title~~T itle XVI, §1689. XVI, §1689.
6 At a minimum, the United States, Russia,6 At a minimum, the United States, Russia, China, Australia, India, France, China, Australia, India, France, Germany, and Japan~~and Germany~~ are developing hypersonic are developing hypersonic
weapons technology. See Richard H. Speierweapons technology. See Richard H. Speier et al., et al., Hypersonic Missile Proliferation: Hindering the Spread of a New
~~Class~~ Class of Weapons, RAND, RAND Corporation, 2017, https://www.rand.org/pubs/research_reports/RR2137.htmlCorporation, 2017, https://www.rand.org/pubs/research_reports/RR2137.html; and Mike Yeo, “Japan unveils its hypersonic weapons plans,” Defense News, March 14, 2020. .
7 When HGVs7 When HGVs are mated with their rocket booster, the resulting weapon system is often referred to as a hypersonic are mated with their rocket booster, the resulting weapon system is often referred to as a hypersonic
boostboost -glide weapon. -glide weapon.
8 U.S.8 U.S. Congress, Senate Committee on Armed Services,Congress, Senate Committee on Armed Services, ~~“Testimony~~ “T estimony of John E. Hyten,” Hearing on United States of John E. Hyten,” Hearing on United States
Strategic Command andStrategic Command and United States Northern Command, February 26, 2019, https://www.armed-services.senate.gov/United States Northern Command, February 26, 2019, https://www.armed-services.senate.gov/
imo/media/doc/Hyten_02-26-19.pdf. imo/media/doc/Hyten_02-26-19.pdf.
9 Richard H. Speier 9 Richard H. Speier et al., et al., Hypersonic Missile Proliferation: Hindering the Spread of a New Class of Weapons, p. 13. , p. 13.
10 See10 See Department of Defense, Department of Defense, 2019 Missile Defense Review, https://www.defense.gov/Portals/1/Interactive/2018/11-, https://www.defense.gov/Portals/1/Interactive/2018/11-
2019-Missile-Defense-Review/2019-Missile-Defense-Review/~~The~~T he%202019%20MDR_Executive%20Summary.pdf. %202019%20MDR_Executive%20Summary.pdf.
11 Richard H. Speier11 Richard H. Speier et al., et al., Hypersonic Missile Proliferation: Hindering the Spread of a New Class of Weapons. .
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Hypersonic Weapons: Background and Issues for Congress

Figure 1. Terrestrial-Based Detection of Ballistic Missiles vs.
Hypersonic Glide Vehicles

Source: CRS image based on an image in “Gliding missiles CRS image based on an image in “Gliding missiles that fly faster than Mach 5 are coming,”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—options and for a defensive system to intercept the attacking weapon—~~potentially~~potential y permitting only permitting only
a single intercept attempt.12a 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, sensor architectures are insufficient to detect and track hypersonic weapons, ~~with~~w ith former 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~~normal y tracks by tracks by ~~satellites~~satel ites in geostationary orbit.”13 Some analysts have suggested that space- 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 weapons—could interceptors or directed energy weapons—could ~~theoretically~~theoretical y present viable options for defending present viable options for defending
against hypersonic weapons in the future.14 Indeed, the against hypersonic weapons in the future.14 Indeed, the 2019 Missile Defense Review notes that notes that
“such sensors take advantage of the large area viewable from space for improved tracking and “such sensors take advantage of the large area viewable from space for improved tracking and
~~potentially~~ potential y targeting of advanced threats, including HGVs and hypersonic cruise missiles.”15 targeting of advanced threats, including HGVs and hypersonic cruise missiles.”15
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.16 As physicist and nuclear expert James Acton explains, “point-area hypersonic weapons defense.16 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 they can only defend ~~small~~ smal areas. To defend the whole of the continental United States, you areas. To defend the whole of the continental United States, you

12 Bradley Perrett et al., “U.S. Navy sees Chinese HGV12 Bradley Perrett et al., “U.S. Navy sees Chinese HGV as part of Wider as part of Wider ~~Threat~~T hreat,” ,” Aviation Week, January 27, 2014. , January 27, 2014.
13 David Vergun,13 David Vergun, “DOD Scaling“DOD Scaling Up Effort to Develop Hypersonics,” Up Effort to Develop Hypersonics,” DoD News, December, December 13, 2018, 13, 2018,
https://dod.defense.gov/News/Article/Article/1712954/dod-scaling-up-effort-to-develop-hypersonics/; see also https://dod.defense.gov/News/Article/Article/1712954/dod-scaling-up-effort-to-develop-hypersonics/; see also
““~~Testimony~~T estimony of Michael Griffin”; and “ of Michael Griffin”; and “~~Testimony~~T estimony of John E. Hyten.” of John E. Hyten.”
14 “14 “~~Testimony~~T estimony of Michael Griffin”; and “ of Michael Griffin”; and “~~Testimony~~T estimony of John E. Hyten.” of John E. Hyten.”
15 Department of Defense, 15 Department of Defense, 2019 Missile Defense Review, p. XVI,, p. XVI, https://www.defense.gov/Portals/1/Interactive/2018/https://www.defense.gov/Portals/1/Interactive/2018/
11-2019-Missile-Defense-Review/11-2019-Missile-Defense-Review/~~The~~T he%202019%20MDR_Executive%20Summary.pdf. %202019%20MDR_Executive%20Summary.pdf.
16 See 16 See James M. Acton, “Hypersonic Weapons Explainer,” Carnegie Endowment for International Peace, April 2, 2018, James M. Acton, “Hypersonic Weapons Explainer,” Carnegie Endowment for International Peace, April 2, 2018,
https://carnegieendowment.org/2018/04/02/hypersonic-weapons-explainer-pub-75957; and Margot van Loon, https://carnegieendowment.org/2018/04/02/hypersonic-weapons-explainer-pub-75957; and Margot van Loon,
“Hypersonic Weapons: A Primer.”“Hypersonic Weapons: A Primer.”
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would need an unaffordable number of THAAD batteries.”17 In addition, some analysts have would need an unaffordable number of THAAD batteries.”17 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.”18 “processing data quickly enough to respond to and neutralize an incoming hypersonic threat.”18
(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 , by ~~Kelley~~ Kel ey M. Sayler and Stephen M. M. Sayler and Stephen M. ~~McCall~~McCal .) .)
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
abilityability to strike hardened or time-sensitive targets with conventional warheads, as to strike hardened or time-sensitive targets with conventional warheads, as ~~well~~ wel as through as through
several Air Force, Army, and DARPA programs.19 Those who support these development efforts several Air Force, Army, and DARPA programs.19 Those who support these development efforts
argue that hypersonic weapons could enhance deterrence, as argue that hypersonic weapons could enhance deterrence, as ~~well~~ wel as provide the U.S. military as provide the U.S. military
with an abilitywith an ability to defeat capabilities such as advanced air and missile defense systems that form to defeat capabilities such as advanced air and missile defense systems that form
the foundation of U.S. competitors’ anti-access/area denial strategies.20 In recognition of this, the the foundation of U.S. competitors’ anti-access/area denial strategies.20 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] “[ensuring the United States] ~~will~~ wil be able to fight and win the wars of the future.”21 be able to fight and win the wars of the future.”21
Similarly, the House Armed Services Committee’s bipartisan Future of Defense Task Force Report notes that hypersonic weapons could present chal enges to the United States in the years to come.22 Programs Unlike ~~Programs~~
~~Unlike~~ programs in China and Russia, U.S. hypersonic weapons are to be programs in China and Russia, U.S. hypersonic weapons are to be ~~conventionally~~conventional y armed. armed.
As a result, U.S. hypersonic weapons As a result, U.S. hypersonic weapons ~~will~~ wil likely require greater accuracy and likely require greater accuracy and ~~will be more~~
~~technically challenging~~wil be more technical y chal enging to develop than nuclear-armed Chinese and Russian systems. Indeed, 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 times less accurate [than a ~~conventionally~~conventional y-armed glider]” due to nuclear blast effects.-armed glider]” due to nuclear blast effects.22
23 According to open-source reporting, the United States According to open-source reporting, the United States ~~has a number of major~~ is conducting research, development, test, and evaluation (RDT&E) on a number of offensive offensive
hypersonic weapons and hypersonic hypersonic weapons and hypersonic technology programstechnology programs ~~in development~~, including the , including the
following (following (~~see Table 1):~~
~~ U.S. Navy—Conventional Prompt Strike (CPS);~~
~~ U.S. Army—Long-Range Hypersonic Weapon (LRHW);~~
~~ U.S. Air Force—AGM-183 Air-Launched Rapid Response Weapon (ARRW,~~
~~pronounced “arrow”);~~

see Table 1): 17 Acton, “Hypersonic Weapons Explainer.” 17 Acton, “Hypersonic Weapons Explainer.”
18 Margot van Loon, “Hypersonic Weapons: A Primer” in 18 Margot van Loon, “Hypersonic Weapons: A Primer” in Defense Technology Program Brief: Hypersonic Weapons, ,
American Foreign Policy Council, May 17, 2019. Some analysts have suggestedAmerican Foreign Policy Council, May 17, 2019. Some analysts have suggested that future command and control that future command and control
systems may require systems may require ~~autonomous~~aut onomous functionality to manage the speed and unpredictability of hypersonic weapons. See functionality to manage the speed and unpredictability of hypersonic weapons. See
John L. Dolan, Richard K. Gallagher,John L. Dolan, Richard K. Gallagher, and David L. Mann, “Hypersonic Weapons Are Literally Unstoppable (As in and David L. Mann, “Hypersonic Weapons Are Literally Unstoppable (As in
America Can’t Stop America Can’t Stop ~~Them~~T hem),” ),” Real Clear Defense, April 23, 2019, https://www.realcleardefense.com/articles/2019/04/, April 23, 2019, https://www.realcleardefense.com/articles/2019/04/
23/hypersonic_weapons__a_threat_to_national_security_114358.html. 23/hypersonic_weapons__a_threat_to_national_security_114358.html.
19 For a full history of U.S.19 For a full history of U.S. hypersonic weapons programs, see CRShypersonic weapons programs, see CRS Report R41464, Report R41464, Conventional Prompt Global
Strike and Long-Range Ballistic Missiles: Background and Issues, by Amy F. Woolf. , by Amy F. Woolf.
20 Roger Zakheim and 20 Roger Zakheim and ~~Tom~~T om Karako, “China’s Hypersonic Missile Advances and U.S. Karako, “China’s Hypersonic Missile Advances and U.S. Defense Responses,” Remarks at 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, Justification Book of Research, Development, ~~Test~~T est and Evaluation, Volume II, Budget and Evaluation, Volume II, Budget Activity 4, p. 580. Activity 4, p. 580.
21 Department of Defense, “Summary of the 2018 National Defense Strategy of 21 Department of Defense, “Summary of the 2018 National Defense Strategy of ~~The~~T he United States of America,” p. 3, United States of America,” p. 3,
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.
22 22 House Armed Services Committee, Future of Defense Task Force Report 2020, September 2020, https://armedservices.house.gov/_cache/files/2/6/26129500 -d208-47ba-a9f7-25a8f82828b0/424EB2008281A3C79BA8C7EA71890AE9.futur e-of-defense-task-force-report.pdf. 23 James M. Acton, “China’s Advanced Weapons,” James M. Acton, “China’s Advanced Weapons,” ~~Testimony~~T estimony to the U.S. China Economic and Security Review to the U.S. China Economic and Security Review
Commission, February 23, 2017, https://carnegieendowment.org/2017/02/23/china-s-advanced-weapons-pub-68095. Commission, February 23, 2017, https://carnegieendowment.org/2017/02/23/china-s-advanced-weapons-pub-68095.
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Hypersonic Weapons: Background and Issues for Congress  U.S. Navy—Conventional Prompt Strike (CPS);  U.S. Army—Long-Range Hypersonic Weapon (LRHW);  U.S. Air Force—AGM-183 Air-Launched Rapid Response Weapon (ARRW, pronounced “arrow”);  U.S. Air Force—Hypersonic Attack Cruise Missile (HACM);  ~~and Issues for Congress~~

 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.programs of record for hypersonic weapons.~~23 Accordingly, funding for U.S. hypersonic weapons~~
~~programs is found in the Research, Development, Test, and Evaluation accounts, rather than in~~
~~Procurement.~~
24 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.common glide vehicle for use across the services.2425 The common glide vehicle is being adapted 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.tested in 2011 and 2017.2526 Once development is complete, “Sandia National Laboratories, the Once development is complete, “Sandia National Laboratories, the
designer of the original concept, then designer of the original concept, then ~~will~~ wil build the common glide vehiclesbuild the common glide vehicles…. ... Booster systems . Booster systems
are being developed separately.”are being developed separately.”26
27 The Navy’s Conventional Prompt Strike (CPS) is expected to pair the common glide vehicle with a booster system to create a common Al Up Round (AUR) for use by both the Navy and Army. According to the Navy’s FY2022 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 FY2028.28 Although Navy officials have previously noted plans to achieve “limited operating capability” on Ohio-class submarines as early as 202529 and to eventual y field hypersonic weapons on Burke-class destroyers, such plans are not reflected in FY2022 budget 24 Steve T rimble, “New Long-T erm ~~The Navy’s Conventional Prompt Strike (CPS) is expected to pair the common glide vehicle with~~
~~a submarine-launched booster system, achieving initial operational capability (IOC) on a~~
~~Virginia-class submarine with Virginia Payload Module in FY2028 and “limited operating~~
~~capability” on Ohio-class submarines as early as 2025.27 Section 1697 of the FY2020 NDAA~~
~~(P.L. 116-92) requires that the Secretary of the Navy also “ensure that the technologies developed~~
~~for the conventional prompt global strike weapon system are transferrable to a surface-launched~~
~~platform,” while Section 1671 of the FY2021 NDAA (P.L. 116-283) directs the Secretary “to~~
~~initiate efforts to integrate [the technologies developed for CPS into Zumwalt-class] destroyers~~
~~during fiscal year 2021.’’ According to former National Security Advisor Robert O’Brien, the~~
~~Navy plans to eventually field hypersonic weapons on both Zumwalt- and Burke-class~~
~~destroyers.28 The Navy is requesting $1 billion for CPS in FY2021—an increase of $415 million~~

~~23 Steve Trimble, “New Long-Term~~ Pentagon Plan Boosts Hypersonics, But Only Prototypes,” Pentagon Plan Boosts Hypersonics, But Only Prototypes,” Aviation Week, March , March
15, 2019, https://aviationweek.com/defense/new-long-term-pentagon-plan-boosts-hypersonics-only-prototypes. 15, 2019, https://aviationweek.com/defense/new-long-term-pentagon-plan-boosts-hypersonics-only-prototypes.
~~24 The~~25 T he services coordinate efforts on a Common Hypersonic Glide services coordinate efforts on a Common Hypersonic Glide Body Board of Directors with rotating chairmanship. Body Board of Directors with rotating chairmanship.
SydneySydney J. Freedberg,J. Freedberg, Jr., “Army Ramps Up FundingJr., “Army Ramps Up Funding For Laser Shield,For Laser Shield, Hypersonic Sword,”Hypersonic Sword,” Breaking Defense, ,
February 28, 2020, https://breakingdefense.com/2020/02/army-ramps-up-funding-for-laser-shield-hypersonic-sword/. February 28, 2020, https://breakingdefense.com/2020/02/army-ramps-up-funding-for-laser-shield-hypersonic-sword/.
2526 Steve Steve ~~Trimble~~T rimble and Guy and Guy Norris, “Sandia’sNorris, “Sandia’s ~~Swerve Could~~ Swerve Could Lead to FirstLead to First -gen Hypersonic Production Line,” -gen Hypersonic Production Line,” Aviation
Week,, October 11, 2018, http://aviationweek.com/air-dominance/sandia-s-swerve-could-lead-first-gen-hypersonic-October 11, 2018, http://aviationweek.com/air-dominance/sandia-s-swerve-could-lead-first-gen-hypersonic-
production-line; and Sydneyproduction-line; and Sydney J. FreedbergJ. Freedberg Jr., “Jr., “ Army Warhead Is Key Army Warhead Is Key ToT o Joint Hypersonics,” Joint Hypersonics,” Breaking Defense, ,
AugustAugust 22, 2018, https://breakingdefense.com/2018/08/army-warhead-is-key-to-joint-hypersonics/. 22, 2018, https://breakingdefense.com/2018/08/army-warhead-is-key-to-joint-hypersonics/.
2627 Steve Steve ~~Trimble~~T rimble and Guy and Guy Norris, “Sandia’sNorris, “Sandia’s ~~Swerve Could~~ Swerve Could Lead to FirstLead to First -gen Hypersonic Production Line,” -gen Hypersonic Production Line,” Aviation
Week,, October 11, 2018, http://aviationweek.com/air-dominance/sandia-s-swerve-could-lead-first-gen-hypersonic-October 11, 2018, http://aviationweek.com/air-dominance/sandia-s-swerve-could-lead-first-gen-hypersonic-
production-line. production-line.
2728 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Navy Justification Book of Research, Development, T est and Evaluat ion, Volume II, Budget Activity 4, p. 1466, https://www.secnav.navy.mil/fmc/fmb/Documents/22pres/RDT EN_BA4_Book.pdf . 29 Department of the Navy, “Highlights of the Department of the Navy FY 2021 Budget,” February 10, 2020, Department of the Navy, “Highlights of the Department of the Navy FY 2021 Budget,” February 10, 2020,
https://www.secnav.navy.mil/fmc/fmb/Documents/21pres/Highlights_book.pdf; and Megan Eckstein, “https://www.secnav.navy.mil/fmc/fmb/Documents/21pres/Highlights_book.pdf; and Megan Eckstein, “ Navy Says Navy Says
Hypersonic Weapons Coming to SubsHypersonic Weapons Coming to Subs in 5 Years,” in 5 Years,” USNI News,, November 17, 2020, November 17, 2020,
https://news.usni.org/2020/11/17/navy-says-hypersonic-weapons-coming-to-subs-in-5-years. https://news.usni.org/2020/11/17/navy-says-hypersonic-weapons-coming-to-subs-in-5-years.
~~28 David B. Larter, “All US Navy destroyers will get hypersonic missiles, says Trump’s national security adviser,”~~
Defense News, October 21, 2020, https://www.defensenews.com/naval/2020/10/21/all-us-navy-destroyers-will-get-
~~hypersonic-missiles-trumps-national-security-advisor-says/.~~
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~~over the FY2020 request and $496 million over the FY2020 appropriation—and $5.3 billion~~
~~across the five-year Future Years Defense Program (FYDP).29~~
documents.30 The Navy is requesting $1.4 bil ion for CPS RDT&E in FY2022—an increase of $366 mil ion over the FY2021 request and $607 mil ion over the FY2021 appropriation.31 U.S. Army
The Army’s Long-Range Hypersonic Weapon program is expected to pair the common glide The Army’s Long-Range Hypersonic Weapon program is expected to pair the common glide
vehicle with the Navy’s booster system. The system is intended to have a range of vehicle with the Navy’s booster system. The system is intended to have a range of over 1,725 ~~1,400~~ miles miles
and “provide the Army with a prototype strategic attack weapon system to defeat A2/AD 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.”3032 The Army is requesting $ The Army is requesting $~~801 million~~301 mil ion in RDT&E for the program in for the program in ~~FY2021—$573 million over~~
~~the FY2020 request and $397 million over the FY2020 appropriation—and $3.3 billion across the~~
~~FYDP.31~~FY2022—$500 mil ion under the FY2021 request and $531 mil ion under the FY2021 appropriation.33 It plans to conduct flight tests for LRHW It plans to conduct flight tests for LRHW ~~from FY2021 to~~in FY2022 and FY2023, field FY2023, field ~~combat rounds~~
in an experimental prototype in FY2023, and transition to a program of record in the fourth quarter of FY2024.FY2023, and transition to a program of record in the fourth quarter of FY2024.32
34 U.S. Air Force
The AGM-183 Air-Launched Rapid Response Weapon is expected to leverage DARPA’s Tactical 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 Boost Glide technology to develop an air-launched hypersonic glide vehicle prototype capable of
~~travelling~~travel ing at average speeds of between Mach 6.5 and Mach 8 at a range of approximately 1,000 at average speeds of between Mach 6.5 and Mach 8 at a range of approximately 1,000
miles.miles.3335 Despite testing delays due to technical Despite testing delays due to technical ~~challenges~~chal enges, ARRW, ARRW successfully completed a successfully completed a
“captive carry” test flight in June 2019; its first free-flight test failed in April“captive carry” test flight in June 2019; its first free-flight test failed in April 2021.2021.3436 The Air Force has requested $238 mil ion for ARRW RDT&E in FY2022—$144 mil ion under the 30 David B. Larter, “All US Navy destroyers will get hypersonic missiles, says T rump’s national security adviser,” Defense News, October 21, 2020, https://www.defensenews.com/naval/2020/10/21/all-us-navy-destroyers-will-get-hypersonic-missiles-trumps-national-security-advisor-says/. 31 Department of Defense Fiscal Year (FY) 2022 ~~The Air~~
~~Force has requested $382 million for ARRW in FY2021—up from $286 million in the FY2020~~
~~request and appropriation—and $581 million across the FYDP, with no funds requested beyond~~
~~FY2022.35 ARRW is a project under the Air Force’s Hypersonics Prototyping Program Element,~~

~~29 Department of Defense Fiscal Year (FY) 2021~~ Budget Estimates, Navy Justification Book of Research, Budget Estimates, Navy Justification Book of Research,
Development, Development, ~~Test~~T est and Evaluation, Volume II, Budget and Evaluation, Volume II, Budget Activity 4, p. Activity 4, p. ~~1419,~~ 1466, https://www.secnav.navy.mil/fmc/fmb/https://www.secnav.navy.mil/fmc/fmb/
~~Documents/21pres/RDTEN_BA4_Book.pdf; see also CRS In Focus IF10831,~~ ~~Defense Primer: Future Years Defense~~
~~Program (FYDP), by Brendan W. McGarry and Heidi M. Peters.~~
~~30 Department of Defense Fiscal Year (FY) 2020 Budget~~ Documents/22p res/RDT EN_BA4_Book.pdf. 32 Sydney J. Freedberg Jr., “Army Discloses Hypersonic LRHW Range Of 1,725 Miles; Watch Out China,” Breaking Defense, May, 12 2021, https://breakingdefense.com/2021/05/army-discloses-hypersonic-lrhw-range-of-1725-miles-watch-out-china/; and 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, Estimates, Army Justification Book of Research,
Development, Development, ~~Test~~T est and Evaluation, Volume II, Budget and Evaluation, Volume II, Budget Activity 4, Activity 4, ~~pp. 579-584,~~ p. 639, https://www.asafm.army.mil/Portals/72/Documents/BudgetMaterial/2022/Base%20Budget/rdte/RDT E_BA_4_FY_2022_PB.pdf. 33 Department of Defense Fiscal Year (FY) 2022~~https://www.asafm.army.mil/~~
~~documents/BudgetMaterial/fy2020/rdte_ba4.pdf; and Sydney J. Freedberg Jr., “Army Sets 2023 Hypersonic Flight~~
~~Test; Strategic Cannon Advances,” Breaking Defense, March 19, 2019, https://breakingdefense.com/2019/03/army-~~
~~sets-2023-hypersonic-flight-test-strategic-cannon-advances/.~~
~~31 Department of Defense Fiscal Year (FY) 2021~~ Budget Estimates, Army Justification Book of Research, Budget Estimates, Army Justification Book of Research,
Development, Development, ~~Test~~T est and Evaluation, Volume II, Budget and Evaluation, Volume II, Budget Activity 4, p. Activity 4, p. ~~613,~~ 639, https://www.asafm.army.mil/Portals/72/https://www.asafm.army.mil/Portals/72/
Documents/BudgetMaterial/Documents/BudgetMaterial/~~2021~~2022/Base%20Budget/rdte//Base%20Budget/rdte/
~~RDTE_BA_4_FY_2021_PB_RDTE_Vol%202_Budget_Activity_4.pdf.~~
~~32 Department of the Army, “FY 2021: President’s Budget Highlights,” February 2020, p. 18~~RDT E_BA_4_FY_2022_PB.pdf. 34 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Army Justification Book of Research , Development, T est and Evaluation, Volume II, Budget Activity 4, ,
https://www.asafm.army.mil/Portals/72/Documents/BudgetMaterial/https://www.asafm.army.mil/Portals/72/Documents/BudgetMaterial/~~2021/pbr/Overview%20and%20Highlights/~~
~~Army_FY_2021_Budget_Highlights.pdf.~~
~~33 ARRW is~~ 2022/Base%20Budget/rdte/RDT E_BA_4_FY_2022_PB.pdf. 35 ARRW is expected to be launchedexpected to be launched initially from the B-52H strategic bomber. initially from the B-52H strategic bomber. ~~Thomas~~T homas Newdick, Newdick, “Air Force Says “Air Force Says
NewNew Hypersonic MissileHypersonic Missile Will Hit Will Hit ~~Targets~~T argets 1,000 Miles Away In Under 12 Minutes,” 1,000 Miles Away In Under 12 Minutes,” The Drive, October 13, 2020, , October 13, 2020,
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-
away-in-under-12-minutes. away-in-under-12-minutes.
3436 Oriana Pawlyk, “Air Force’s Hypersonic ARRW Missile Oriana Pawlyk, “Air Force’s Hypersonic ARRW Missile ~~Fails~~ Fails First Flight First Flight ~~Test~~T est,” ,” Military.com , April 6, 2021, , April 6, 2021,
https://www.military.com/daily-news/2021/04/06/air-forces-hypersonic-arrw-missile-fails-first-flighthttps://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. test.html#:~:text=In%20June%202019%2C%20the%20service,early%202020s%2C%20the%20release%20states.
~~35 Department of Defense Fiscal Year (FY) 2021 Budget Estimates, Air Force Justification Book of Research,~~
~~Development, Test and Evaluation, Volume II, p. 121, https://www.saffm.hq.af.mil/Portals/84/documents/FY21/~~
~~RDTE_/FY21%20Air%20Force%20Research%20Development%20Test%20and%20Evaluation%20Vol%20II.pdf?~~
~~ver=2020-02-12-145218-377.~~
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~~which is intended to demonstrate concepts “to [enable] leadership to make informed strategy and~~
~~resource decisions … for future programs.”36~~
FY2021 request and $148 mil ion under the FY2021 appropriation.37 In addition, the Air Force has requested $161 mil ion in FY2022 for the procurement of an estimated 12 ARRW missiles.38 In February 2020, the Air Force announced that it had In February 2020, the Air Force announced that it had ~~cancelled~~cancel ed its second hypersonic weapon 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 vehiclethe common glide vehicle and booster system, due to budget pressures that forced it to choose between ARRW and , due to budget pressures that forced it to choose between ARRW and
HCSW.HCSW.3739 Then-Air Force acquisition chief Then-Air Force acquisition chief ~~Will~~ Wil Roper explained that ARRW was selected Roper explained that ARRW was selected
because it was more advanced and gave the Air Force additional options. “[ARRW] because it was more advanced and gave the Air Force additional options. “[ARRW] is smal er~~is smaller~~; we ; we
~~can carry twice as many on the B-52, and it’s possible it could be on the F-15,” he explained.38~~
~~The Air Force was to continue its technical review of HCSW through March 2020.39~~
~~Finally, the Air Force is reportedly seeking information from industry on the Expendable~~
~~Hypersonic Air-Breathing Multi-Mission Demonstrator Program, also known as “Mayhem.”~~
~~Mayhem is reported to be larger than ARRW and capable of carrying multiple payloads for~~
~~different mission sets.40~~
~~DARPA~~
~~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~~
~~technologies to enable future air-launched, tactical-range hypersonic boost glide systems.”41 TBG~~
~~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~~
~~$117 million—down from the $162 million FY2020 request and the $152 million FY2020~~
~~appropriation—for TBG in FY2021.42~~
~~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~~
~~defenses and rapidly and precisely engage critical time sensitive targets.” DARPA has requested~~

~~36 Ibid., p. 121.~~
~~37 Valerie Insinna, “US Air Force kills one of its hypersonic weapons programs,” Defense News, February 10, 2020,~~
~~https://www.defensenews.com/smr/federal-budget/2020/02/10/the-air-force-just-canceled-one-of-its-hypersonic-~~
~~weapons-programs/.~~
~~38 John A. Tirpak, “Roper: The ARRW Hypersonic Missile Better Option for USAF,” March 2, 2020,~~
~~https://www.airforcemag.com/arrw-beat-hcsw-because-its-smaller-better-for-usaf/. Tirpak~~can carry twice as many on the B-52, and it’s possible it could be on the F-15,” he explained.40 A senior Air Force official has since noted that a B-52 could potential y carry four ARRWs.41 Final y, 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 technologies. Some reports indicate that HACM is intended to be launched from both bombers and fighter aircraft, with a senior Air Force official noting that a B-52 could potential y carry 20 HACMs or more.42 According to the Air Force, “the ability to execute HACM development is contingent upon fully funded and successful predecessor capability development efforts.”43 The Air Force requested $200 mil ion for HACM in FY2022.44 The Air Force is also seeking information from industry on the Expendable Hypersonic Air-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 next step in what the opportunity space al ows relative to hypersonic cruise missile systems” and is intended to be capable of flying “significantly longer ranges than what we’re doing today.”45 37 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Air Force Justification Book of Research, Development, T est and Evaluation, Volume II, p. 139, https://www.saffm.hq.af.mil/Portals/84/documents/FY22/RDT E_/FY22%20DAF%20J-Book%20-%203600%20-%20AF%20RDT %20and%20E%20Vol%20II.pdf?ver=KpJJbVq68o32dSvkjuv_Iw%3d%3d. 38 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Air Force Justification Book of Missile Procurement, Volume I, p. 19, 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. 39 Valerie Insinna, “US Air Force kills one of its hypersonic weapons programs,” Defense News, February 10, 2020, https://www.defensenews.com/smr/federal-budget/2020/02/10/the-air-force-just-canceled-one-of-its-hypersonic-weapons-programs/. 40 John A. T irpak, “Roper: T he ARRW Hypersonic Missile Better Option for USAF,” Air Force Magazine, March 2, 2020, https://www.airforcemag.com/arrw-beat-hcsw-because-its-smaller-better-for-usaf/. T irpak additionally notes that ~~additionally notes that~~ “the “the
F-15 could accelerate the ARRW to Mach 3 before launch, potentially reducing the size of the booster needed to get 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.” weapon to hypersonic speed.”
~~39 Ibid.~~
~~40 See, for example, Rachel S. Cohen, “Hypersonic Attack Cruise Missile Becomes High-Priority USAF Project,”~~ ~~Air~~
~~Force Magazine, October 13, 2020, https://www.airforcemag.com/hypersonic-attack-cruise-missile-becomes-high-~~
~~priority-usaf-project/.~~
~~41 “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,” Aviation Week, July 27, 2017,~~
~~https://aviationweek.com/defense/us-air-force-plans-road-map-operational-hypersonics.~~
~~42 DARPA states that the decline in the budget request “reflects completion of full-scale testing and final program~~
~~reporting.” Department of Defense Fiscal Year (FY) 2021 Budget Estimates, Defense Advanced Research Projects~~
~~Agency, Defense-Wide Justification Book 1 of 5, pp. 162-164, https://comptroller.defense.gov/Portals/45/Documents/~~
~~defbudget/fy2021/budget_justification/pdfs/03_RDT_and_E/~~
~~RDTE_Vol1_DARPA_MasterJustificationBook_PB_2021.pdf.~~
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~~Hypersonic Weapons: Background and Issues for Congress~~

~~$40 million for OpFires in FY2021—down from the $50 million FY2020 request and~~
~~appropriation—and intends to transition the program to the Army.43~~
~~In the longer term, DARPA, with Air Force support, is continuing work on the Hypersonic Air-~~
~~breathing Weapon Concept, which “seeks to develop and demonstrate critical technologies to~~
~~enable an effective and affordable air-launched hypersonic cruise missile.”44 Principal Director~~
~~for Hypersonics Mike White has stated that such a missile would be smaller than DOD’s~~
~~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~~
~~integrate seekers more easily than hypersonic glide vehicles.45 DARPA requested $7 million to~~
~~develop HAWC in FY2021—down from the $10 million FY2020 request and $20 million~~
~~FY2020 appropriation.46~~
~~Table 1. Summary of U.S. Hypersonic Weapons Programs~~
~~FY2020~~
~~PB2021~~
~~Title~~
~~($ in millions)~~
~~($ in millions)~~
~~Schedule~~
~~Conventional Prompt~~
~~512~~
~~1,008~~
~~IOC in FY2028~~
~~Strike (CPS)~~
~~Long-Range Hypersonic~~
~~404~~
~~801~~
~~Flight tests through 2023~~
~~Weapon (LRHW)~~
~~AGM-183 Air-Launched~~
~~286~~
~~382~~
~~Flight tests through 2022~~
~~Rapid Response Weapon~~
~~(ARRW)~~
~~Hypersonic Conventional~~
~~290~~
0
~~Cancelled in 2020~~
~~Strike Weapon (HCSW)~~
~~Tactical Boost Glide~~
~~152~~
~~117~~
~~Testing through at least~~
~~(TBG)~~
~~2021~~
~~Operational Fires~~
50
40
~~Testing through at least~~
~~(OpFires)~~
~~2021; transitions to~~
~~weapon system~~
~~integration planning and~~
~~design in 2021~~
~~Hypersonic Air-breathing~~
20
7
~~Complete flight tests in~~
~~Weapon Concept~~
~~2020; final program~~
~~(HAWC)~~
~~reviews in 2021~~
Source: Program information taken from U.S. Navy, Army, Air Force, and DARPA FY2021 Justification Books,
~~available at https://comptroller.defense.gov/Budget-Materials/.~~

~~43 Department of Defense Fiscal Year (FY) 2021 Budget Estimates, Defense Advanced Research Projects Agency,~~
~~Defense-Wide Justification Book 1 of 5, p. 165,~~ 41 John A. T irpak, “Air Force Will T ry Again to Launch ARRW Hypersonic Missile in July,” Air Force Magazine, June 3, 2021, https://www.airforcemag.com/air-force-july-launch-arrw-hypersonic-missile/. 42 John A. T irpak, “Air Force Will T ry Again to Launch ARRW Hypersonic Missile in July,” Air Force Magazine, June 3, 2021, https://www.airforcemag.com/air-force-july-launch-arrw-hypersonic-missile/. 43 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Air Force Justification Book of Research, Development, T est and Evaluation, Volume II, p. 148, https://www.saffm.hq.af.mil/Portals/84/documents/FY22/RDT E_/FY22%20DAF%20J-Book%20-%203600%20-%20AF%20RDT %20and%20E%20Vol%20II.pdf?ver=KpJJbVq68o32dSvkjuv_Iw%3d%3d. 44 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Air Force Justification Book of Research, Development, T est and Evaluation, Volume II, p. 139, https://www.saffm.hq.af.mil/Portals/84/documents/FY22/RDT E_/FY22%20DAF%20J-Book%20-%203600%20-%20AF%20RDT %20and%20E%20Vol%20II.pdf?ver=KpJJbVq68o32dSvkjuv_Iw%3d%3d. 45 Mike White, Remarks at the Center for Strategic and International Studies, “Hypersonic Strike and Defense: A Congressional Research Service 7 Hypersonic Weapons: Background and Issues for Congress Mayhem is reported to be larger than ARRW and capable of carrying multiple payloads for different mission sets.46 DARPA 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 technologies to enable future air-launched, tactical-range hypersonic boost glide systems.”47 TBG wil “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 $50 mil ion for TBG in FY2022—$67 mil ion under the FY2021 request and $32 mil ion under the FY2021 appropriation.48 DARPA’s Operational Fires reportedly seeks to leverage TBG technologies to develop a ground-launched system that wil enable “advanced tactical weapons to penetrate modern enemy air defenses and rapidly and precisely engage critical time sensitive targets.” DARPA has requested $45 mil ion for OpFires in FY2022—$5 mil ion over the FY2021 request and $3 mil ion under the FY2022 appropriation.49 In the longer term, DARPA, with Air Force support, is continuing work on the Hypersonic Air- breathing Weapon Concept, which “seeks to develop and demonstrate critical technologies to enable an effective and affordable air-launched hypersonic cruise missile.”50 Principal Director for Hypersonics Mike White has stated that such a missile would be smal er than DOD’s hypersonic glide vehicles and could therefore launch from a wider range of platforms. Principal Director White has additional y noted that HAWC and other hypersonic cruise missiles could integrate seekers more easily than hypersonic glide vehicles.51 DARPA requested $10 mil ion to develop HAWC in FY2022—$10 mil ion under the FY2021 request and $21 mil ion under the FY2021 appropriation.52 Conversation with Mike White,” June 10, 2021, https://www.csis.org/analysis/hypersonic-strike-and-defense-conversation-mike-white. 46 See, for example, Rachel S. Cohen, “Hypersonic Attack Cruise Missile Becomes High -Priority USAF Project,” Air Force Magazine, October 13, 2020, https://www.airforcemag.com/hypersonic-attack-cruise-missile-becomes-highpriority-usaf-project/. 47 “T actical Boost Glide (T BG) Program Information,” DARPA, https://www.darpa.mil/program/tactical-boost-glide; and Guy Norris, “U.S. Air Force Plans Road Map to Operational Hypersonics,” Aviation Week, July 27, 2017, https://aviationweek.com/defense/us-air-force-plans-road-map-operational-hypersonics. 48 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Defense Advanced Research Projects Agency, Defense-Wide Justification Book 1 of 5, p. 158, https://comptroller.defense.gov/Portals/45/Documents/defbudget/fy2022/budget_justification/pdfs/03_RDT _and_E/RDT E_Vol1_DARPA_MasterJustificationBook_PB_2022.pdf . 49 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Defense Advanced Research Projects Agency, Defense-Wide Justification Book 1 of 5, p. 159, https://comptroller.defense.gov/Portals/45/Documents/defbudget/fy2022~~https://comptroller.defense.gov/Portals/45/Documents/defbudget/~~
~~fy2021~~/budget_justification/pdfs//budget_justification/pdfs/~~03_RDT_and_E/RDTE_Vol1_DARPA_MasterJustificationBook_PB_2021.pdf.~~
4403_RDT _and_E/RDT E_Vol1_DARPA_MasterJustificationBook_PB_2022.pdf . 50 “Hypersonic Air-breathing Weapon Concept (HAWC) Program Information,” DARPA, https://www.darpa.mil/ “Hypersonic Air-breathing Weapon Concept (HAWC) Program Information,” DARPA, https://www.darpa.mil/
program/hypersonic-air-breathing-weapon-concept. program/hypersonic-air-breathing-weapon-concept.
4551 “Department of Defense Press Briefing on Hypersonics,” March 2, 2020, https://www.defense.gov/Newsroom/ “Department of Defense Press Briefing on Hypersonics,” March 2, 2020, https://www.defense.gov/Newsroom/
~~Transcripts/Transcript~~T ranscripts/T ranscript/Article/2101062/department/Article/2101062/department -of-defense-press-briefing-on-hypersonics/. -of-defense-press-briefing-on-hypersonics/.
4652 Department of Defense Fiscal Year (FY) Department of Defense Fiscal Year (FY) ~~2021~~2022 Budget Estimates, Defense Advanced Budget Estimates, Defense Advanced Research Projects Agency, Research Projects Agency,
Defense-Wide Justification Book 1 of 5, p. Defense-Wide Justification Book 1 of 5, p. ~~165,~~ 161, https://comptroller.defense.gov/Portals/45/Documents/defbudget/https://comptroller.defense.gov/Portals/45/Documents/defbudget/
~~fy2021~~fy2022/budget_justification/pdfs//budget_justification/pdfs/~~03_RDT_and_E/RDTE_Vol1_DARPA_MasterJustificationBook_PB_2021~~03_RDT _and_E/RDT E_Vol1_DARPA_MasterJustificationBook_PB_2022.pdf. .pdf.
Congressional Research Service Congressional Research Service

8 8

Hypersonic Weapons: Background and Issues for Congress

~~Hypersonic Missile Defenses47~~
Table 1. Summary of U.S. Hypersonic Weapons RDT&E Funding FY2021 Request FY2021 Enacted PB2022 Title ($ in millions) ($ in millions) ($ in millions) Schedule Conventional 1,008 767 1,374 Platform Prompt Strike (CPS) deployment in FY2025 and FY2028 Long-Range 801 832 301 Prototype Hypersonic deployment in Weapon (LRHW) FY2023 AGM-183 Air- 382 386 238 Early operational Launched Rapid capability in FY2022 Response Weapon (ARRW) Hypersonic Attack 0 0 200 Complete critical Cruise Missile design review in (HACM) FY2023 Tactical Boost Glide 117 82 50 Continue tests in (TBG) FY2022 Operational Fires 40 48 45 Complete critical (OpFires) design review in FY2022 Hypersonic Air- 20 31 10 Complete final breathing Weapon program review in Concept (HAWC) FY2022 Source: Program information taken from U.S. Navy, Army, Air Force, and DARPA FY202 2 Justification Books, available at https://comptrol er.defense.gov/Budget-Materials/. Hypersonic Missile Defenses53 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 Michael Griffin has stated that the United States ~~will~~ wil not have a defensive capability against not have a defensive capability against
hypersonic weapons until the mid-2020s, at the earliest.hypersonic weapons until the mid-2020s, at the earliest.4854 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.4955 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 interceptor. This proposals for a Hypersonic Defense Regional Glide Phase Weapons System interceptor. This
effort is intended to “reduce interceptor key technology and integration risks, anchor modeling effort is intended to “reduce interceptor key technology and integration risks, anchor modeling
and simulation in areas of large uncertainty, and to increase the interceptor technology readiness 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).levels (TRL) to level 5” (validating components in a relevant environment).5056 MDA has also 53 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. 54 “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, https://dod.defense.gov/News/T ranscripts/T ranscript -View/Article/1713396/media-availability-with-deputy-secretary-shanahan-and-under-secretary-of-defens/. 55 P.L. 114-840, Section 2, Division A, T itle XVI, §1687; and Hudson and T rimble, “T op U.S. Hypersonic Weapon Program”; Steve T rimble, “A Hypersonic Sputnik?,” p. 21. 56 Missile Defense Agency, “Draft Request for Prototype Proposal: Hypersonic Defense Regional Glide Phase Weapon Congressional Research Service 9 Hypersonic Weapons: Background and Issues for Congress ~~MDA has also~~
awarded four companies—Northrop Grumman, Raytheon, Leidos, and L3Harris—with $20 awarded four companies—Northrop Grumman, Raytheon, Leidos, and L3Harris—with $20
~~million~~ mil ion contracts to design prototype space-based (low-Earth orbit) sensors by October 31, contracts to design prototype space-based (low-Earth orbit) sensors by October 31,
2020.2020.5157 Such sensors could Such sensors could ~~theoretically~~theoretical y extend the range at which incoming missiles could be extend the range at which incoming missiles could be
detected and tracked—a critical requirement for hypersonic missile defense, according to then-detected and tracked—a critical requirement for hypersonic missile defense, according to then-
USD(R&E) Griffin.USD(R&E) Griffin.5258 MDA requested $ MDA requested $~~206.8 million~~248 mil ion for hypersonic defense in for hypersonic defense in ~~FY2021~~FY2022—up —up
from from its $207 mil ion FY2021 request and down from the $273 mil ion FY2021 appropriation.59 In ~~its $157.4 million FY2020 request—and $659 million across the FYDP.53 In~~ addition, addition,
DARPA is working on a program DARPA is working on a program ~~called~~cal ed Glide Breaker, which “ Glide Breaker, which “~~will~~ wil develop critical component develop critical component
technology to support a lightweight vehicle designed for precise engagement of hypersonic technology to support a lightweight vehicle designed for precise engagement of hypersonic
threats at very long range.”threats at very long range.”5460 DARPA requested $ DARPA requested $~~3 million~~7 mil ion for Glide Breaker in for Glide Breaker in ~~FY2021—down~~
~~from $10 million in FY2020.55~~
FY2022, matching the $7 mil ion appropriation in FY2021.61 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),5662 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

~~47 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.~~
~~48 “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, https://dod.defense.gov/News/Transcripts/~~
~~Transcript-View/Article/1713396/media-availability-with-deputy-secretary-shanahan-and-under-secretary-of-defens/.~~
~~49 P.L. 114-840, Section 2, Division A, Title XVI, §1687; and Hudson and Trimble, “Top U.S. Hypersonic Weapon~~
~~Program”; Steve Trimble, “A Hypersonic Sputnik?,” p. 21.~~
~~50 Missile Defense Agency, “Draft Request for Prototype Proposal: Hypersonic Defense Regional Glide Phase Weapon~~
~~System,” 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, https://techlinkcenter.org/technology-readiness-level-dod/.~~
51 Sandra Erwin, “Missile Defense Agency selects four companies to develop space sensors,” Space News, hypersonic technologies for defense systems development through 2030.63 These specialized facilities, which simulate the unique conditions experienced in hypersonic flight (e.g., speed, pressure, heating),64 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 industry or academic facilities.65 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, System,” January 30, 2020, p. 8. T RL measures a technology’s level of maturity; T RL 5 requires validation in a relevant environment. For information about specific T RLs, see T roy Carter, “ The 9 T echnology Readiness Levels of the DOD,” T echLink, https://techlinkcenter.org/technology-readiness-level-dod/. 57 Sandra Erwin, “Missile Defense Agency selects four compan ies to develop space sensors,” Space News, October 30, October 30,
2019, https://spacenews.com/missile-defense-agency-selects-four-companies-to-develop-space-sensors/. Experts 2019, https://spacenews.com/missile-defense-agency-selects-four-companies-to-develop-space-sensors/. Experts
disagreedisagree on the cost and technological feasibility of space-basedon the cost and technological feasibility of space-based ~~missile~~ missile defense. defense.
5258 Media Availability With Deputy Secretary Shanahan and Under Secretary of Defense Griffin.” Media Availability With Deputy Secretary Shanahan and Under Secretary of Defense Griffin.”
~~53 Missile Defense Agency, Budget Estimates Overview: Fiscal Year 2021, p. 12, https://www.mda.mil/global/~~
~~documents/pdf/budgetfy21.pdf.~~
54 59 Department of Defense Fiscal Year (FY) 2022 Budget Est imates, Missile Defense Agency, Defense-Wide Justification Book 2a of 5, p. 569, https://comptroller.defense.gov/Portals/45/Documents/defbudget/fy2022/budget_justification/pdfs/03_RDT _and_E/RDT E_Vol2_MDA_RDT E_PB22_Justification_Book.pdf. 60 Department of Defense Fiscal Year (FY) 2021 Budget Estimates, Defense Advanced Department of Defense Fiscal Year (FY) 2021 Budget Estimates, Defense Advanced ~~Research Projects Agency,~~
~~Defense-Wide Justification Book 1 of 5, p. 164.~~
~~55 Ibid.~~
~~56 P.L. 112-239, Section 2, Division A, Title X, §1071.~~
~~Congressional Research Service~~

9

~~link to page 25~~ ~~Hypersonic Weapons: Background and Issues for Congress~~

~~hypersonic technologies for defense systems development through 2030.57 These specialized~~
~~facilities, which simulate the unique conditions experienced in hypersonic flight (e.g., speed,~~
~~pressure, heating),58 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~~
~~industry or academic facilities.59 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,~~
~~coupled aerodynamic and thermal-loading environments for flight durations necessary to evaluate~~
~~these characteristics above Mach 8.”~~
~~Since the 2014 study report was published~~ Research Projects Agency, Defense-Wide Justification Book 1 of 5, p. 164. 61 Department of Defense Fiscal Year (FY) 2022 Budget Estimates, Defense Advanced Research Projects Agency, Defense-Wide Justification Book 1 of 5, p. 160, https://comptroller.defense.gov/Portals/45/Documents/defbudget/fy2022/budget_justification/pdfs/03_RDT _and_E/RDT E_Vol1_DARPA_MasterJustificationBook_PB_2022.pdf. 62 P.L. 112-239, Section 2, Division A, T itle X, §1071. 63 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, Hypersonic Weapons: DOD Should Clarify Roles and Responsibilities to Ensure Coordination across Developm ent Efforts, GAO-21-378, March 22, 2021, p. 15, https://www.gao.gov/products/gao-21-378. 64 T hese conditions additionally require the development of specialized materials such as metals and ceramics. 65 T his 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) Study on the Ability of the U.S. Test and Evaluation Infrastructure to Effectively and Efficiently Mature Hypersonic Technologies for Defense System s Developm ent: Sum mary Analysis and Assessm ent, Institute for Defense Analyses, September 2014. Permission to use this material has been granted by the Office of Science and T echnology Policy. Congressional Research Service 10 link to page 25 Hypersonic Weapons: Background and Issues for Congress coupled aerodynamic and thermal-loading environments for flight durations necessary to evaluate these characteristics above Mach 8.” 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 , 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.6066 In addition, the University of Arizona In addition, the University of Arizona ~~plans to modify~~
modified one of its wind tunnels to enable Mach 5 testingone of its wind tunnels to enable Mach 5 testing ~~by early 2021~~, while Texas A&M University—in , while Texas A&M University—in
partnership with Army partnership with Army Futures Command—Futures Command—~~plans to complete construction of~~is constructing a kilometer-long a kilometer-long
Mach 10 wind tunnelMach 10 wind tunnel ~~by 2021.61~~.67 (For a (For a partial list of U.S. hypersonic test assets and their capabilities, list of U.S. hypersonic test assets and their capabilities,
see see thethe Appendix.) The United States also uses the Royal Australian Air Force Woomera Test ) 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.Range in Australia and the Andøya Rocket Range in Norway for flight testing.6268 In January 2019, In January 2019,
the Navy announced plans to reactivate its Launch Test Complex at China Lake, CAthe Navy announced plans to reactivate its Launch Test Complex at China Lake, CA, to improve to improve
air launch and underwater testing capabilities for the conventional prompt strike program.air launch and underwater testing capabilities for the conventional prompt strike program.63
69 According to an assessment conducted by the Government According to an assessment conducted by the Government Accountability Office, DOD has Accountability Office, DOD has
dedicated approximately $1 dedicated approximately $1 ~~billion~~ bil ion to hypersonic facility to hypersonic facility modernization from FY2015 to modernization from FY2015 to
FY2024.FY2024.6470
In April In April 2020, DOD’s Office of Inspector General announced that it would be evaluating current 2020, DOD’s Office of Inspector General announced that it would be evaluating current
ground test and evaluation facilities to determine if the capability and capacity would be ground test and evaluation facilities to determine if the capability and capacity would be

~~57 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,~~
~~Hypersonic Weapons: DOD Should Clarify Roles and Responsibilities to Ensure Coordination across Development~~
~~Efforts, GAO-21-378, March 22, 2021, p. 15, https://www.gao.gov/products/gao-21-378.~~
~~58 These conditions additionally require the development of specialized materials such as metals and ceramics.~~
~~59 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) 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~~
~~Office of Science and Technology Policy.~~
~~60 Oriana Pawlyk, “Air Force Expanding Hypersonic Technology Testing at Two~~sufficient to execute DOD’s planned test schedule.71 Similarly, Section 222 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 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 testing capabilities and infrastructure that may be required to support in-flight and ground-based testing for such weapons.” In addition, 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 66 Oriana Pawlyk, “Air Force Expanding Hypersonic T echnology T esting at T wo Indiana Universities,” Military.com, Indiana Universities,” Military.com,
April 23, 2019, https://www.military.com/daily-news/2019/04/23/air-force-expanding-hypersonic-technology-testing-April 23, 2019, https://www.military.com/daily-news/2019/04/23/air-force-expanding-hypersonic-technology-testing-
two-indiana-universities.html. two-indiana-universities.html.
6167 University of Arizona, “Mach 5 Quiet Ludwieg University of Arizona, “Mach 5 Quiet Ludwieg ~~Tube~~ T ube,” https://transition.arizona.edu/facilities/qlt5?_ga=,” https://transition.arizona.edu/facilities/qlt5?_ga=
2.62515882.768526379.15828431922.62515882.768526379.1582843192 -983632914.1582843192; and Ashley -983632914.1582843192; and Ashley ~~Tressel, “~~T ressel, “ Army to open hypersonic testing Army to open hypersonic testing
facility at facility at ~~Texas~~T exas A&M,” Inside Defense, October 13, 2019, https://insidedefense.com/daily-news/army-open- 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 Institute of ~~Technology~~T echnology, the Georgia Institute of , the Georgia Institute of ~~Technology~~T echnology, the Air Force Academy, the University of , the Air Force Academy, the University of ~~Tennessee~~T ennessee, and , and
VirginiaVirginia Polytechnic Institute and State University also maintain experimental hypersonic facilities or conduct Polytechnic Institute and State University also maintain experimental hypersonic facilities or conduct
hypersonic research. hypersonic research.
6268 (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.
6369 “Update: US Navy to develop China Lake to support CPS weapon testing,” “Update: US Navy to develop China Lake to support CPS weapon testing,” Jane’s (subscription required),(subscription required), February February
12, 2019, https://janes.ihs.com/Janes/Display/FG_1644858-JMR. 12, 2019, https://janes.ihs.com/Janes/Display/FG_1644858-JMR.
6470 Government Accountability Office, Government Accountability Office, Hypersonic Weapons: DOD Should Clarify Roles and Responsibilities to Ensure
Coordination across ~~Development~~Developm ent Efforts, GAO-21-378, March 22, 2021, p. 27, https://www.gao.gov/products/gao-21-378. 71 See Department of Defense Office of Inspector General, “Memorandum for Distribution: Evaluation of the Gro und T est and Evaluation Infrastructure Supporting Hypersonic Capabilities (Project No. D2020 -DEV0SN-0106.000),” April 13, 2020, https://media.defense.gov/2020/Apr/14/2002280826/-1/-1/1/D2020-DEV0SN-0106.000.PDF. Congressional Research Service 11 link to page 16 Hypersonic Weapons: Background and Issues for Congress chain.72 DOD has also amended its “5000 series” acquisition policy in order to enhance supply chain resiliency and reduce sustainment costs.73 ~~Efforts, GAO-21-378, March 22, 2021, p. 27, https://www.gao.gov/products/gao-21-~~
~~378.~~
~~Congressional Research Service~~

10

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

~~sufficient to execute DOD’s planned test schedule.65 Similarly, Section 222 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 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 testing capabilities~~
~~and infrastructure that may be required to support in-flight and ground-based testing for such~~
~~weapons.”~~
~~In addition, 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~~
~~chain.66 DOD has also amended its “5000 series” acquisition policy in order to enhance supply~~
~~chain resiliency and reduce sustainment costs.67~~
Russia
Although Russia has conducted research on hypersonic weapons technology since the 1980s, it 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 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-and Europe, and in response to the U.S. withdrawal from the Anti-~~Ballistic~~Bal istic Missile Treaty in Missile Treaty in
2001.2001.6874 Detailing Russia’s concerns, President Putin stated that “the US is permitting constant, Detailing Russia’s concerns, President Putin stated that “the US is permitting constant,
uncontrolled growth of the number of anti-uncontrolled growth of the number of anti-~~ballistic~~bal istic missiles, improving their quality, and creating missiles, improving their quality, and creating
new missile launching areas. If we do not do something, new missile launching areas. If we do not do something, ~~eventually this will~~ eventual y this wil result in the result in the
complete devaluation of Russia’s nuclear potential. Meaning that complete devaluation of Russia’s nuclear potential. Meaning that ~~all~~ al of our missiles could simply of our missiles could simply
be intercepted.”be intercepted.”6975 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.70
76 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 KinzhalZircon)—and has reportedly fielded the Kinzhal (“Dagger”), a maneuvering air-launched (“Dagger”), a maneuvering air-launched ~~ballistic~~
bal istic missile.missile.71

~~65 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),”~~
~~April 13, 2020, https://media.defense.gov/2020/Apr/14/2002280826/-1/-1/1/D2020-DEV0SN-0106.000.PDF.~~
6677 Avangard (Figure 2) is a hypersonic glide vehicle launched from an intercontinental bal istic missile (ICBM), giving it “effectively ‘unlimited’ range.”78 Reports indicate that Avangard is currently deployed on the SS-19 Stiletto ICBM, though Russia plans to eventual y launch the vehicle from the Sarmat ICBM. Sarmat is stil in development, although it is scheduled to be deployed by the end of 2022.79 Avangard features onboard countermeasures and wil reportedly 72 Aaron Mehta, “Pentagon launches hypersonic industrial base study,” Aaron Mehta, “Pentagon launches hypersonic industrial base study,” Defense News,, March 3, 2020, March 3, 2020,
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/.
~~67 C. Todd~~73 C. T odd Lopez, “Rewrite of Acquisition Regulation Helps U.S. Lopez, “Rewrite of Acquisition Regulation Helps U.S. ~~Build~~ Build Hypersonic Arsenal More Quickly,”Hypersonic Arsenal More Quickly,” DOD
News,, October 30, 2020, https://www.defense.gov/Explore/News/Article/Article/2400205/rewrite-of-acquisition-October 30, 2020, 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/.
6874 United Nations Office of Disarmament Affairs, United Nations Office of Disarmament Affairs, Hypersonic Weapons: A Challenge and Opportunity for Strategic
~~Arms~~Arm s Control, February, February 2019, https://www.un.org/disarmament/publications/more/hypersonic-weapons-a-challenge-2019, https://www.un.org/disarmament/publications/more/hypersonic-weapons-a-challenge-
and-opportunity-for-strategic-arms-control/. and-opportunity-for-strategic-arms-control/.
6975 Vladimir Vladimir Putin, “Presidential Address to the Federal Assembly,”Putin, “Presidential Address to the Federal Assembly,” March 1, 2018, http://en.kremlin.ru/events/March 1, 2018, http://en.kremlin.ru/events/
president/news/56957. president/news/56957.
7076 In this instance, “strategic stability” refers to a “bilateral nuclear relationship of mutual vulnerability.” See In this instance, “strategic stability” refers to a “bilateral nuclear relationship of mutual vulnerability.” See ~~Tong~~ T ong
Zhao, “Conventional Challenges to Strategic Stability: Chinese Perceptions of Hypersonic Zhao, “Conventional Challenges to Strategic Stability: Chinese Perceptions of Hypersonic ~~Technology~~T echnology and the Security and the Security
Dilemma,” Carnegie-Dilemma,” Carnegie-~~Tsinghua~~ T singhua Center for GlobalCenter for Global Policy, July 23, 2018, https://carnegietsinghua.org/2018/07/23/Policy, July 23, 2018, 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.
7177 Although the Kinzhal is a maneuvering air-launched ballistic missile 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 —and because it poses defensive challenges that are similar to other hypersonic weapons—it is included here for reference. 78 Steve T rimble, “A Hypersonic Sputnik?,” Aviation Week, January 14-27, 2019, p. 20. 79 Nicholas Fiorenza, “Putin outlines development of Russia’s nuclear triad,” Jane’s Defence Weekly (subscription required), April 22, 2021, 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 systems,” Jane’s (subscription required), https://janes.ihs.com/Janes/Display/FG_899127-JIR. Congressional Research Service 12 Hypersonic Weapons: Background and Issues for Congress ~~rather than a hypersonic glide vehicle or~~
~~Congressional Research Service~~

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~~link to page 15~~

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

~~Avangard (Figure 2) is a hypersonic glide vehicle launched from an intercontinental ballistic~~
~~missile (ICBM), giving it “effectively ‘unlimited’ range.”72 Reports indicate that Avangard is~~
~~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 is scheduled to be~~
~~deployed by the end of 2022.73 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 2019.7480
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.7581 These sources assert that Tsirkon was successfully launched from a Project 22350 frigate in January and October 2020.82 U.S. intel igence reports indicate that the missile wil become operational in 2023.83 In addition, Russia has reportedly fielded Kinzhal, a maneuvering air-launched bal istic missile modified from the Iskander missile. According to U.S. intel igence 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.84 Russia plans to deploy the missile on both the MiG-31 and the Su-34 long-range strike 80 “First regiment of Avangard hypersonic missile systems goes on combat duty in Russia,” TASS, December 27, 2019, https://tass.com/defense/1104297. 81 “Russia makes over 10 test launches of T sirkon ~~These sources assert~~

~~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~~
~~reference.~~
~~72 Steve Trimble, “A Hypersonic Sputnik?,” Aviation Week, January 14-27, 2019, p. 20.~~
~~73 Nicholas Fiorenza, “Putin outlines development of Russia’s nuclear triad,” Jane’s Defence Weekly (subscription~~
~~required), April 22, 2021, 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~~
~~systems,” Jane’s (subscription required), https://janes.ihs.com/Janes/Display/FG_899127-JIR.~~
~~74 “First regiment of Avangard hypersonic missile systems goes on combat duty in Russia,” TASS, December 27, 2019,~~
~~https://tass.com/defense/1104297.~~
~~75 “Russia makes over 10 test launches of Tsirkon~~ seaborne hypersonic missile,” seaborne hypersonic missile,” TASS, December 21, 2018, , December 21, 2018,
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, https://www.dia.mil/portals/27/documents/news/, Defense Intelligence Agency, 2017, p. 79, 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.
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~~Hypersonic Weapons: Background and Issues for Congress~~

~~that Tsirkon was successfully launched from a Project 22350 frigate in January and October~~
~~2020.76 U.S. intelligence reports indicate that the missile will become operational in 2023.77~~
~~In addition, Russia has reportedly fielded Kinzhal, a maneuvering air-launched ballistic 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.78 Russia plans to deploy the missile on both the MiG-31 and the Su-34 long-range strike~~
~~fighter.79~~82 “T ASS: Russia Conducts First Ship-Based Hypersonic Missile T est,” Reuters, February 27, 2020, https://www.voanews.com/europe/tass-russia-conducts-first-ship-based-hypersonic-missile-test; and Associated Press, “Russia reports successful test launch of hypersonic missile,” October 7, 2020, https://apnews.com/article/vladimir-putin-archive-russia-20688205e30f19a8d76fcd77cb9d45a4. 83 Amanda Macias, “Russia again successfully tests ship-based hypersonic missile—which will likely be ready for combat by 2022,” CNBC, December 20, 2018, 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 T sirkon hypersonic missile for service in 2023—source,” TASS, March 20, 2019, http://tass.com/defense/1049572. 84 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, https://www.cnbc.com/2018/07/13/russia-new-hypersonic-missile-likely-ready-for-war-by-2020.html. Congressional Research Service 13 Hypersonic Weapons: Background and Issues for Congress fighter.85 Russia is working to mount the missile on the Tu-22M3 strategic bomber (NATO code Russia is working to mount the missile on the Tu-22M3 strategic bomber (NATO code
name: Backfire), although the slower-moving bomber may face name: Backfire), although the slower-moving bomber may face ~~challenges~~chal enges in “accelerating the in “accelerating the
weapon into the correct launch parameters.”weapon into the correct launch parameters.”80
86 Russian media has reported Kinzhal’s top speed as Mach 10, with a range of up to 1,200 miles 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-31. The Kinzhal is reportedly capable of maneuverable flight, as when launched from the MiG-31. The Kinzhal is reportedly capable of maneuverable flight, as
~~well~~ wel as of striking both ground and naval targets, and could as of striking both ground and naval targets, and could ~~eventually~~eventual y be fitted with a nuclear 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. publicly verified by U.S. ~~intelligence~~intel igence agencies, and have been met with skepticism by a number agencies, and have been met with skepticism by a number
of analysts.of analysts.8187
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.82

~~76 “TASS: Russia Conducts First Ship-Based Hypersonic Missile Test,” Reuters, February 27, 2020,~~
~~https://www.voanews.com/europe/tass-russia-conducts-first-ship-based-hypersonic-missile-test; and Associated Press,~~
~~“Russia reports successful test launch of hypersonic missile,” October 7, 2020, https://apnews.com/article/vladimir-~~
~~putin-archive-russia-20688205e30f19a8d76fcd77cb9d45a4.~~
~~77 Amanda Macias, “Russia again successfully tests ship-based hypersonic missile—which will likely be ready for~~
~~combat by 2022,” CNBC, December 20, 2018, 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 in~~
~~2023—source,” TASS, March 20, 2019, http://tass.com/defense/1049572.~~
~~78 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, https://www.cnbc.com/2018/07/13/russia-new-hypersonic-missile-likely-~~
~~ready-for-war-by-2020.html.~~
~~79 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.~~
~~80 Dave Majumdar, “Russia: New Kinzhal Aero-Ballistic Missile~~ 88 China According to Tong Zhao, a fel ow at the Carnegie-Tsinghua Center for Global Policy, “most 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. military technology,” such as U.S. regional missile defenses.89 In particular, China’s pursuit of hypersonic 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 infrastructure. U.S. missile defense deployments could then limit China’s ability to conduct a retaliatory strike against the United States.90 China has demonstrated a growing interest in Russian advances in hypersonic weapons technology, conducting flight tests of a hypersonic-glide vehicle (HGV) only days after Russia tested its own system.91 Furthermore, a January 2017 report found that over half of open-source 85 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. 86 Dave Majumdar, “Russia: New Kinzhal Aero-Ballistic Missile Has 3,000 km Range if Fired from Supersonic Has 3,000 km Range if Fired from Supersonic
Bomber,” Bomber,” The National Interest, July 18, 2018, https://nationalinterest.org/blog/buzz/russia-new-kinzhal-aero-ballistic-, July 18, 2018, https://nationalinterest.org/blog/buzz/russia-new-kinzhal-aero-ballistic-
missile-has-3000-km-range-if-fired-supersonic-bomber. missile-has-3000-km-range-if-fired-supersonic-bomber.
8187 David Axe, “Is Kinzhal, Russia’s David Axe, “Is Kinzhal, Russia’s ~~New~~ New Hypersonic Missile, a GameHypersonic Missile, a Game Changer?,” Changer?,” The Daily Beast, March 15, 2018, , March 15, 2018,
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.
8288 “Aerodynamics,” Central Aerohydrodynamic Institute, http://tsagi.com/research/aerodynamics/; “Russia announces “Aerodynamics,” Central Aerohydrodynamic Institute, http://tsagi.com/research/aerodynamics/; “Russia announces
successfulsuccessful flight test of Avangard hypersonic glideflight test of Avangard hypersonic glide vehicle,” vehicle,” Jane’s (subscription required),(subscription required), January 3, 2019, January 3, 2019,
https://janes.ihs.com/Janes/Display/FG_1451630-JMR; and “https://janes.ihs.com/Janes/Display/FG_1451630-JMR; and “ Avangard system isAvangard system is tested, saidtested, said to be fully ready for to be fully ready for
deployment,” Russian Strategic Nuclear Forces, December 26, 2018, http://russianforces.org/blog/2018/12/deployment,” Russian Strategic Nuclear Forces, December 26, 2018, http://russianforces.org/blog/2018/12/
avangard_system_is_tested_said.shtml. avangard_system_is_tested_said.shtml.
~~Congressional Research Service~~

13

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

~~China~~
~~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~~
~~China] is the necessity to counter specific security threats from increasingly sophisticated U.S.~~
~~military technology,” such as U.S. regional missile defenses.83 In particular, China’s pursuit of~~
~~hypersonic 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 infrastructure. U.S. missile defense deployments could then limit China’s ability to~~
~~conduct a retaliatory strike against the United States.84~~
~~China has demonstrated a growing interest in Russian advances in hypersonic weapons~~
~~technology, conducting flight tests of a hypersonic-glide vehicle (HGV) only days after Russia~~
~~tested its own system.85 Furthermore, a January 2017 report found that over half of open-source~~
89 T ong Zhao, “Conventional Challenges to Strategic Stability: Chinese Perceptions of Hypersonic T echnology and the Security Dilemma.” 90 T ong Zhao, “Conventional Challenges to Strategic Stability”; and Lora Saalman, “China’s Calculus on Hypersonic Glide,” August 15, 2017, Stockholm International Peace Research Institute, https://www.sipri.org/commentary/topical-backgrounder/2017/chinas-calculus-hypersonic-glide. 91 Lora Saalman, “China’s Calculus on Hypersonic Glide.” Congressional Research Service 14 Hypersonic Weapons: Background and Issues for Congress Chinese papers on hypersonic weapons include references to Russian weapons programs.Chinese papers on hypersonic weapons include references to Russian weapons programs.8692 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 context. Indeed, some analysts believe that China may be planning to mate ~~conventionally~~conventional y armed armed
HGVs with the DF-21 and DF-26 HGVs with the DF-21 and DF-26 ~~ballistic~~bal istic missiles in support of an anti-access/area denial missiles in support of an anti-access/area denial
strategy.strategy.8793 China has reportedly not made a final determination as to whether its hypersonic China has reportedly not made a final determination as to whether its hypersonic
weapons weapons ~~will~~ wil be nuclear- or be nuclear- or ~~conventionally~~conventional y-armed—or dual-capable.-armed—or dual-capable.
Programs
China has conducted a number of successful tests of the DF-17, a medium-range China has conducted a number of successful tests of the DF-17, a medium-range ~~ballistic~~bal istic missile missile
~~specifically~~specifical y designed to launch HGVs. U.S. designed to launch HGVs. U.S. ~~intelligence~~ intel igence analysts assess that the missile has a 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.8894 China has also tested China has also tested
the DF-41 intercontinental the DF-41 intercontinental ~~ballistic~~bal istic missile, which could be modified to carry a conventional or 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.89
95 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

~~83 Tong Zhao, “Conventional Challenges to Strategic Stability: Chinese Perceptions of Hypersonic Technology and the~~
~~Security Dilemma.”~~
~~84 Tong Zhao, “Conventional Challenges to Strategic Stability”; and Lora Saalman, “China’s Calculus on Hypersonic~~
~~Glide,” August 15, 2017, Stockholm International Peace Research Institute, https://www.sipri.org/commentary/topical-~~
~~backgrounder/2017/chinas-calculus-hypersonic-glide.~~
~~85 Lora Saalman, “China’s Calculus on Hypersonic Glide.”~~
~~86 Lora Saalman, “Factoring Russia into the US-China Equation on Hypersonic Glide Vehicles,”~~ 1,200 miles and have stated that the vehicle may be capable of performing “extreme maneuvers” during flight.96 Although unconfirmed by intel igence agencies, some analysts believe the DF-ZF could have become operational as early as 2020.97 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 2018.98 China claims the vehicle reached top speeds of Mach 6 and executed a series of in-flight maneuvers before landing.99 Unlike the DF-ZF, Starry Sky-2 is a “waverider” that uses powered flight after launch and derives 92 Lora Saalman, “Factoring Russia into the US-China Equation on Hypersonic Glide Vehicles,” SIPRI, January 2017, SIPRI, January 2017,
https://www.sipri.org/sites/default/files/Factoring-Russia-into-US-Chinese-equation-hypersonic-glide-vehicles.pdf. https://www.sipri.org/sites/default/files/Factoring-Russia-into-US-Chinese-equation-hypersonic-glide-vehicles.pdf.
8793 Lora Saalman, “China’s Calculus Lora Saalman, “China’s Calculus on Hypersonic Glide”;on Hypersonic Glide”; and Malcolm Clausand Malcolm Claus and Andrewand Andrew ~~Tate~~ T ate, “Chinese hypersonic , “Chinese hypersonic
programme reflects regional priorities,” programme reflects regional priorities,” Jane’s (subscription required), (subscription required), March 12, 2019, https://janes.ihs.com/Janes/March 12, 2019, https://janes.ihs.com/Janes/
Display/FG_1731069-JIR. Display/FG_1731069-JIR.
8894 Ankit Panda, “Introducing the DF-17: China’s Newly Ankit Panda, “Introducing the DF-17: China’s Newly ~~Tested~~ T ested Ballistic Missile Ballistic Missile Armed with a Hypersonic Glide Armed with a Hypersonic Glide
Vehicle,”Vehicle,” The National Interest, December, December 28, 2017, https://thediplomat.com/2017/12/introducing-the-df-17-chinas-28, 2017, https://thediplomat.com/2017/12/introducing-the-df-17-chinas-
newly-tested-ballistic-missile-armed-with-a-hypersonic-glide-vehicle/; and Bill Gertz, “newly-tested-ballistic-missile-armed-with-a-hypersonic-glide-vehicle/; and Bill Gertz, “ China’s new hypersonic China’s new hypersonic
missile,” missile,” Washington Times, October 2, 2019, https://www.washingtontimes.com/news/2019/oct/2/china-shows-df-17-, October 2, 2019, https://www.washingtontimes.com/news/2019/oct/2/china-shows-df-17-
hypersonic-missile/. hypersonic-missile/.
8995 U.S.-China Economic and Security Review Commission 2018 Annual Report, p. 235, https://www.uscc.gov/sites/, p. 235, 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.
~~Congressional Research Service~~

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~~link to page 19~~ ~~Hypersonic Weapons: Background and Issues for Congress~~

~~1,200 miles and have stated that the vehicle may be capable of performing “extreme maneuvers”~~
~~during flight.90 Although unconfirmed by intelligence agencies, some analysts believe the DF-ZF~~
~~could have become operational as early as 2020.91~~
~~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 2018.92 China claims the vehicle~~
~~reached top speeds of Mach 6 and executed a series of in-flight maneuvers before landing.93~~
~~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~~
~~2025.94 U.S. officials have declined to comment on the program.95~~
~~Infrastructure~~
~~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~~
~~many hypersonic tests as the United States.96 China tested three hypersonic vehicle models (D18-~~
~~1S, D18-2S, and D18-3S)—each with different aerodynamic properties—in September 2018.97~~
~~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 6+~~
~~high-speed engine, or “scramjet,” test bed (Figure 3) to research thermal resistant components~~
~~and hypersonic cruise missile technologies.98~~

~~90 “Gliding missiles~~ 96 “Gliding missiles that fly faster than Mach 5 are coming,” that fly faster than Mach 5 are coming,” The Economist, April 6, 2019, , April 6, 2019,
https://www.economist.com/science-and-technology/2019/04/06/gliding-missiles-thathttps://www.economist.com/science-and-technology/2019/04/06/gliding-missiles-that -fly-faster-than-mach-5-are--fly-faster-than-mach-5-are-
coming; and Franz-Stefan Gady,coming; and Franz-Stefan Gady, ~~“China Tests~~ “ China T ests New Weapon Capable of Breaching US New Weapon Capable of Breaching US ~~Missile~~ Missile Defense Systems,”Defense Systems,” The
~~Diplomat~~Diplom at, April 28, 2016, https://thediplomat.com/2016/04/china-tests-new-weapon-capable-of-breaching-u-s-missile-, April 28, 2016, https://thediplomat.com/2016/04/china-tests-new-weapon-capable-of-breaching-u-s-missile-
defense-systems/. defense-systems/.
9197 U.S.-China Economic and Security Review Commission 2015 Annual Report, p. 20, https://www.uscc.gov/sites/, p. 20, https://www.uscc.gov/sites/
default/files/annual_reports/2015%20Annual%20Report%20to%20Congress.PDF. default/files/annual_reports/2015%20Annual%20Report%20to%20Congress.PDF.
9298 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, https://media.defense.gov/2019/May/02/2002127082/-1/-1/1/May 2, 2019, p. 44, https://media.defense.gov/2019/May/02/2002127082/-1/-1/1/
~~2019_CHINA_MILITARY_POWER_REPORT.pdf.~~
~~93 Jessie~~ 2019_CHINA_MILIT ARY_POWER_REPORT.pdf . 99 Jessie Yeung, “China claims to have successfullyYeung, “China claims to have successfully tested its first hypersonic aircraft, tested its first hypersonic aircraft, CNN, August, August 7, 2018, 7, 2018,
https://www.cnn.com/2018/08/07/china/china-hypersonic-aircrafthttps://www.cnn.com/2018/08/07/china/china-hypersonic-aircraft -intl/index.html. Congressional Research Service 15 link to page 19 Hypersonic Weapons: Background and Issues for Congress lift from its own shockwaves. Some reports indicate that the Starry Sky-2 could be operational by 2025.100 U.S. officials have declined to comment on the program.101 Infrastructure 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 many hypersonic tests as the United States.102 China tested three hypersonic vehicle models (D18-1S, D18-2S, and D18-3S)—each with different aerodynamic properties—in September 2018.103 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 6+ high-speed engine, or “scramjet,” test bed (Figure 3) to research thermal resistant components and hypersonic cruise missile technologies.104 Figure 3. Lingyun-1 Hypersonic Cruise Missile Prototype Source: Photo accompanying Drake Long, “China reveals Lingyun-1 hypersonic missile ~~-intl/index.html.~~
~~94 U.S.-China Economic and Security Review Commission Report 2015, p. 20.~~
~~95 Bill Gertz, “China Reveals Test of New Hypersonic Missile,” The Washington Free Beacon, August 10, 2018,~~
~~https://freebeacon.com/national-security/chinas-reveals-test-new-hypersonic-missile/.~~
~~96 U.S.-China Economic and Security Review Commission Report 2015, p. 20.~~
~~97 Malcolm Claus and Andrew Tate, “Chinese hypersonic programme reflects regional priorities,” Jane’s (subscription~~
~~required), March 12, 2019, https://janes.ihs.com/Janes/Display/FG_1731069-JIR.~~
~~98 Jeffrey Lin and P.W. Singer, “China’s hypersonic military projects include spaceplanes and rail guns,”~~ ~~Popular~~
~~Mechanics, June 26, 2018, https://www.popsci.com/chinas-hypersonic-work-speeds-up.~~
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~~Hypersonic Weapons: Background and Issues for Congress~~

~~Figure 3. Lingyun-1 Hypersonic Cruise Missile Prototype~~

~~Source:~~ ~~Photo accompanying Drake Long, “China reveals Lingyun-1 hypersonic missile~~ at National Science and 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.”99105 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.~~100~~106 China also operates the JF-12 100 U.S.-China Economic and Security Review Commission Report 2015, p. 20. 101 Bill Gertz, “China Reveals T est of New Hypersonic Missile,” The Washington Free Beacon, August 10, 2018, https://freebeacon.com/national-security/chinas-reveals-test-new-hypersonic-missile/. 102 U.S.-China Economic and Security Review Commission Report 2015 , p. 20. 103 Malcolm Claus and Andrew T ate, “Chinese hypersonic programme reflects regional priorities ~~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 10 and Mach 15101; it is~~
~~reportedly in the process of building a wind tunnel capable of reaching speeds of Mach 25.102~~
~~China is known to have tested hypersonic weapons at the Jiuquan Satellite Launch Center and the~~
~~Taiyuan Satellite Launch Center.~~

~~99 Andrew Tate, “China conducts further tests with hypersonic vehicles,” Janes Defence Weekly (subscription~~
~~required), October 2, 2018, https://customer.janes.com/DefenceWeekly/Display/FG_1120806-JDW.~~
~~100 Kelvin Wong, “China claims successful test of hypersonic waverider~~,” ,” Jane’s (subscription required),(subscription required), ~~August 10,~~
~~2018~~ March 12, 2019, https://janes.ihs.com/Janes/Display/, https://janes.ihs.com/Janes/Display/~~FG_1002295-JDW; and Ellen Nakashima and Gerry Shih, “China builds~~
~~advanced weapons systems using American chip technology,” Washington Post, April 9, 2021.~~
~~101~~FG_1731069-JIR. 104 Jeffrey Lin and P.W. Singer, Jeffrey Lin and P.W. Singer, ~~“A look at China’s most exciting hypersonic aerospace programs,” Popular Science,~~
~~April 18, 2017~~ “China’s hypersonic military projects include spaceplanes and rail guns,” Popular Mechanics, June 26, 2018, https://www.popsci.com/chinas-hypersonic-, https://www.popsci.com/chinas-hypersonic-~~technology.~~
~~102 Andrew Tate~~work-speeds-up. 105 Andrew T ate, “China conducts further tests with hypersonic vehicles,” , “China conducts further tests with hypersonic vehicles,” ~~Janes~~Jane’s Defence Weekly (subscription (subscription
required),required), October 2, 2018, https://customer.janes.com/DefenceWeekly/Display/FG_1120806-JDW.October 2, 2018, https://customer.janes.com/DefenceWeekly/Display/FG_1120806-JDW.
106 Kelvin Wong, “China claims successful test of hypersonic waverider,” Jane’s (subscription required), August 10, Congressional Research Service Congressional Research Service

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Hypersonic Weapons: Background and Issues for Congress 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 15107; it is reportedly in the process of building a wind tunnel capable of reaching speeds of Mach 25.108 China is known to have tested hypersonic weapons at the Jiuquan Satel ite Launch Center and the Taiyuan Satel ite Launch Center. ~~and Issues for Congress~~

Global Hypersonic Weapons Programs
Although the United States, Russia, and China possess Although the United States, Russia, and China possess the most advanced hypersonic weapons programs,the most advanced hypersonic weapons programs, a a
number of other countries—including Australia,number of other countries—including Australia, India, France, Germany,India, France, Germany, and Japan—are also developing and Japan—are also developing
hypersonic weapons technology. Since 2007, the United States has hypersonic weapons technology. Since 2007, the United States has ~~collaborated~~col aborated with Australia with Australia on the Hypersonic on the Hypersonic
International Flight Research Experimentation (HIFiRE) programInternational Flight Research Experimentation (HIFiRE) program to develop hypersonic technologies.to develop hypersonic technologies. The most The most
recent HIFiRE test, recent HIFiRE test, ~~successfully~~successful y conducted in July 2017, explored the flight dynamics of a Mach 8 hypersonic glide conducted in July 2017, explored the flight dynamics of a Mach 8 hypersonic glide
vehicle,vehicle, while previous tests explored scramjetwhile previous tests explored scramjet engine technologies.engine technologies. HIFiRE’s successor,HIFiRE’s successor, the Southern Cross the Southern Cross
Integrated Flight Research Experiment (SCIFiRE) program,Integrated Flight Research Experiment (SCIFiRE) program, is to further develop hypersonic air-breathing is to further develop hypersonic air-breathing
technologies.technologies. SCIFiRE demonstration tests are expected by the mid-2020s. In addition to the WoomeraSCIFiRE demonstration tests are expected by the mid-2020s. In addition to the Woomera Test Test
Range facilities—oneRange facilities—one of the largest weapons test facilitiesof the largest weapons test facilities in the world—Australiain the world—Australia ~~reportedly~~ reportedly operates seven 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 similarlyIndia has similarly ~~collaborated~~ col aborated with Russia on the development of BrahMos II, a Mach 7 hypersonic cruise missile. with Russia on the development of BrahMos II, a Mach 7 hypersonic cruise missile.
Although BrahMos II was Although BrahMos II was ~~initially~~ initial y intended to be fielded in 2017, news reports indicate that the program intended to be fielded in 2017, news reports indicate that the program ~~faces~~fa ces
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 cruiseIndia is also developing an indigenous, dual-capable hypersonic cruise ~~missile~~ missile as part of its Hypersonic Technology as part of its Hypersonic Technology
DemonstratorDemonstrator Vehicle programVehicle program ~~and successfully~~ and successful y tested a Mach 6 scramjet tested a Mach 6 scramjet in June 2019 and Septemberin June 2019 and September 2020. India 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 France also has ~~collaborated~~col aborated and contracted with Russia on the development of hypersonic technology. Although and contracted with Russia on the development of hypersonic technology. Although
France has been investing in hypersonic technology researchFrance has been investing in hypersonic technology research since the 1990s, it has only recently announced its since the 1990s, it has only recently announced its
intent to weaponize the technology. Under the V-max (Experimental Maneuvering Vehicle) program,intent to weaponize the technology. Under the V-max (Experimental Maneuvering Vehicle) program, France plans France plans
to modify its air-to-surface ASN4G supersonic missileto modify its air-to-surface ASN4G supersonic missile for hypersonic flight by 2022. Somefor hypersonic flight by 2022. Some analysts believeanalysts believe that the that the
V-max program is intended to provide France with a strategic nuclear weapon.V-max program is intended to provide France with a strategic nuclear weapon. France operates five hypersonic 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 Germany ~~successfully~~ successful y tested an experimental hypersonic glide vehicle (SHEFEX II) in 2012; however, reports tested an experimental hypersonic glide vehicle (SHEFEX II) in 2012; however, reports
indicate that Germanyindicate that Germany may have may have ~~pulled~~pul ed funding for the program. German funding for the program. German defense contractor DLR continues to defense contractor DLR continues to
research and test hypersonic vehicles as part of the European Union’s ATLLASresearch and test hypersonic vehicles as part of the European Union’s ATLLAS II project, which seeksII project, which seeks to design a to design a
Mach 5-6 vehicle.Mach 5-6 vehicle. Germany operates three hypersonic wind tunnels and is capable of testing speeds of up to Germany operates three hypersonic wind tunnels and is capable of testing speeds of up to
Mach 11. Mach 11.
~~Finally,~~ Final y, Japan is developing the Hypersonic CruiseJapan is developing the Hypersonic Cruise ~~Missile~~ Missile (HCM) and the Hyper Velocity Gliding Projectile (HCM) and the Hyper Velocity Gliding Projectile
(HVGP). According to(HVGP). According to Jane’s, Japan invested $122 , Japan invested $122 ~~million~~ mil ion in HVGP in FY2019. It reportedlyin HVGP in FY2019. It reportedly plans to field plans to field ~~one~~
~~HVGP warhead for neutralizing aircraft carriers and one for area suppression—both in the 2024 to 2028~~
~~timeframe. The warheads are expected to enter service~~ HVGPs 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 Exploration Agency in 2030. The Japan Aerospace Exploration Agency
operates three hypersonic wind tunnels, with two additional facilitiesoperates three hypersonic wind tunnels, with two additional facilities at Mitsubishi Heavy Industries and the at Mitsubishi Heavy Industries and the
University of Tokyo. University of Tokyo.
Other countries—including Iran, Israel,Other countries—including Iran, Israel, and South Korea—haveand South Korea—have conducted foundational researchconducted foundational research on hypersonic on hypersonic
airflowsairflows and propulsion systems,and propulsion systems, but may not bebut may not be pursuing a hypersonic weapons capability at this time. pursuing a hypersonic weapons capability at this time.
Note: For additional ~~information~~ information about global hypersonic weapons programs, see Richard H. Speier et al., Hypersonic
Missile Proliferation. For information about Japan’s hypersonic weapons research and development plans, see Mike Yeo,
“Japan unveils its hypersonic weapons plans,” Defense News, March 14, 2020. 2018, https://janes.ihs.com/Janes/Display/FG_1002295-JDW; and Ellen Nakashima and Gerry Shih, “ China builds advanced weapons systems using American chip techno logy,” Washington Post, April 9, 2021. 107 Jeffrey Lin and P.W. Singer, “A look at China’s most exciting hypersonic aerospace programs,” Popular Science, April 18, 2017, https://www.popsci.com/chinas-hypersonic-technology. 108 Andrew T ate, “China conducts further tests with hypersonic vehicles,” Janes Defence Weekly (subscription required), October 2, 2018, https://customer.janes.com/DefenceWeekly/Display/FG_1120806-JDW. Congressional Research Service 17 Hypersonic Weapons: Background and Issues for Congress ~~14, 2020.~~
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, and their implications for strategic the rationale for hypersonic weapons, their expected costs, and their implications for strategic
stability and arms control. This section provides an overview of some of these questions. stability and arms control. This section provides an overview of some of these questions.
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
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for hypersonic weapons or long-term funding plans.for hypersonic weapons or long-term funding plans.~~103~~109 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 chal enges.”110 ~~and challenges.”104~~
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 alternative means of executing these mission sets, and an assessment of the enabling analysis of alternative means of executing these mission sets, and an assessment of the enabling
technologies—such as space-based sensors or autonomous command and control systems—that technologies—such as space-based sensors or autonomous command and control systems—that
may be required to employ or defend against hypersonic weapons. For example, Section 1671 of 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 Chiefs of Staff, in 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 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 defense committees a report on strategic hypersonic weapons, including “a description of how the
requirements for land and sea-based hypersonic weapons requirements for land and sea-based hypersonic weapons ~~will~~ wil be addressed with the Joint be addressed with the Joint
Requirements Oversight Council, and how such requirements Requirements Oversight Council, and how such requirements ~~will be formally~~wil be formal y provided to the provided to the
military departments procuring such weapons.” This report is to military departments procuring such weapons.” This report is to ~~additionally~~additional y include “the include “the
potential target sets for hypersonic weapons ... and the required mission planning to support potential target sets for hypersonic weapons ... and the required mission planning to support
targeting by the United States Strategic Command and other combatant commands.”targeting by the United States Strategic Command and other combatant commands.”
Funding and Management Considerations
Principal Director for Hypersonics (USD[R&E]) Mike White has noted that DOD is prioritizing Principal Director for Hypersonics (USD[R&E]) Mike White has noted that DOD is prioritizing
offensive programs while it determines “the path forward to get a robust defensive strategy.”offensive programs while it determines “the path forward to get a robust defensive strategy.”~~105~~111
This approach is reflected in DOD’s This approach is reflected in DOD’s ~~FY2021 request, which allocates $206.8 million for~~
recent budget requests. For example, DOD requested $247.9 mil ion for hypersonic defense programs and $3.8 bil ion for hypersonic weapons programs in FY2022.112 Similarly, in FY2021, DOD requested $206.8 mil ion for hypersonic defense programs and $3.2 bil ion for hypersonic weapons programs.113 109 Steve T rimble, “New Long-T erm Pentagon Plan Boosts Hypersonics.” 110 Steve T rimble, “New Long-T erm Pentagon Plan Boosts Hypersonics.” 111 Aaron Mehta, “Is the Pentagon Moving Quickly Enough on Hypersonic Defense?” Defense News, ~~hypersonic defense programs—of a total $3.2 billion request for all hypersonic-related~~
~~research.106 Similarly, in FY2020, DOD requested $157.4 million for hypersonic defense~~
~~programs—of a total $2.6 billion for all hypersonic-related research.~~
~~Although the Defense Subcommittees of the Appropriations Committees increased FY2020~~
~~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~~
~~hypersonic research has the potential to result in stove-piped, proprietary systems that duplicate~~
~~capabilities and increase costs.”107 To mitigate this concern, they appropriated $100 million for~~
~~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~~
~~consortium for hypersonic research and workforce development” in support of DOD efforts.108~~

~~103 Steve Trimble, “New Long-Term Pentagon Plan Boosts Hypersonics.”~~
~~104 Steve Trimble, “New Long-Term Pentagon Plan Boosts Hypersonics.”~~
105 Aaron Mehta, “Is the Pentagon Moving Quickly Enough on Hypersonic Defense?” Defense News, March 21, 2019, March 21, 2019,
https://www.defensenews.com/pentagon/2019/03/21/is-the-pentagon-moving-quickly-enough-on-hypersonic-defense/. https://www.defensenews.com/pentagon/2019/03/21/is-the-pentagon-moving-quickly-enough-on-hypersonic-defense/.
~~106Department~~112 Department of Defense Fiscal Year (FY) of Defense Fiscal Year (FY) ~~2021~~2022 Budget Estimates, Missile Budget Estimates, Missile Defense Agency DefenseDefense Agency Defense -Wide -Wide
Justification Book VolumeJustification Book Volume 2a of 5, p. 2a of 5, p. ~~10,~~ 569, https://comptroller.defense.gov/Portals/45/Documents/defbudget/https://comptroller.defense.gov/Portals/45/Documents/defbudget/~~fy2021/~~
~~budget_justification/pdfs/03_RDT_and_E/RDTE_Vol2_MDA_RDTE_PB21_Justification_Book.pdf.~~
~~107 “Department of Defense Appropriations Act, 2020: Joint Explanatory Statement,” Defense Subcommittees of the~~
~~Appropriations Committees, December 16, 2019, https://appropriations.house.gov/sites/~~
~~democrats.appropriations.house.gov/files/HR%201158%20-%20Division%20A%20-~~
~~%20Defense%20SOM%20FY20.pdf.~~
~~108 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~~
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~~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).109 UCAH~~ fy2022/budget_ justification/pdfs/03_RDT _and_E/RDT E_Vol2_MDA_RDT E_PB22_Justification_Book.pdf. 113 Department of Defense Fiscal Year (FY) 2021 Budget Estimates, Missile Defense Agency Defense -Wide Justification Book Volume 2a of 5, p. 10, https://comptroller.defense.gov/Portals/45/Documents/defbudget/fy2021/ Congressional Research Service 18 Hypersonic Weapons: Background and Issues for Congress Although the Defense Subcommittees of the Appropriations Committees increased FY2020 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 hypersonic research has the potential to result in stove-piped, proprietary systems that duplicate capabilities and increase costs.”114 To mitigate this concern, they appropriated $100 mil ion for 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 consortium for hypersonic research and workforce development” in support of DOD efforts.115 DOD established the JHTO in April 2020 and announced on October 26, 2020, that it awarded Texas A&M University with a $20 mil ion contract—renewable for up to $100 mil ion—to manage a University Consortium for Applied Hypersonics (UCAH).116 UCAH is to be overseen is to be overseen
by a group of academic researchers from Texas A&M University, the Massachusetts Institute of by a group of academic researchers from Texas A&M University, the Massachusetts Institute of
Technology, the University of Minnesota, the University of Technology, the University of Minnesota, the University of ~~Illinois~~Il inois at Urbana-Champaign, the at Urbana-Champaign, the
University of Arizona, the University of Tennessee Space Institute, Morgan State University, 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, California Institute of Technology, Purdue University, the University of California-Los Angeles,
and the Georgia Institute of Technology.and the Georgia Institute of Technology.~~110~~117 The consortium is to “facilitate transitioning academic The consortium is to “facilitate transitioning academic
research into developing systems [as research into developing systems [as ~~well~~ wel as] work with the department to reduce system as] work with the department to reduce system
development timelines while maintaining quality control standards.”development timelines while maintaining quality control standards.”~~111~~
118 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.~~112~~119
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~~chal enging for Congress to evaluate the balance of funding for hypersonic weapons programs, for Congress to evaluate the balance of funding for hypersonic weapons programs,
enabling technologies, supporting test infrastructure, and hypersonic missile defense. budget_justification/pdfs/03_RDT _and_E/RDT E_Vol2_MDA_RDT E_PB21_Justification_Book.pdf . 114 “Department of Defense Appropriations Act, 2020: Joint Explanatory Statement,” Defense Subcommittees of the Appropriations Committees, December 16, 2019, https://appropriations.house.gov/sites/democrats.appropriations.house.gov/files/HR%201158%20-%20Division%20A%20-%20Defense%20SOM%20FY20.pdf. 115 Ibid. T he Joint Hypersonic T ransition Office, then called the Joint T echnology Office on Hypersonics, was originally mandated by Section 218 of the FY2007 NDAA ( P.L. 109-364). The office was redesignated as the Joint Hypersonics T ransition Office and given additional authorities in Section 214 of the FY2018 NDAA ( ~~enabling technologies, supporting test infrastructure, and hypersonic missile defense.~~
~~Strategic Stability~~
~~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~~
~~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~~
~~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~~
~~facilities.~~
~~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~~
~~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~~
~~in nature, regardless of how it was perceived by the State firing the weapon, and decide that a~~

~~Hypersonics Transition Office and given additional authorities in Section 214 of the FY2018 NDAA (~~P.L. 115-91). 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. into agreements with institutions of higher learning. ~~The~~T he office went unfunded office went unfunded until FY2020 and wasuntil FY2020 and was not established not established
until April 2020. until April 2020.
~~109~~116 David Vergun, David Vergun, “DOD Awards“DOD Awards ~~Applied~~ Applied Hypersonics Contract to Hypersonics Contract to ~~Texas~~T exas A&M University,” A&M University,” DOD News, October 26, , October 26,
2020, https://www.defense.gov/Explore/News/Article/Article/2394438/dod-awards-applied-hypersonics-contract-to-2020, https://www.defense.gov/Explore/News/Article/Article/2394438/dod-awards-applied-hypersonics-contract-to-
texas-am-university/. texas-am-university/.
~~110~~117 Ibid. Ibid.
~~111~~118 Ibid. Ibid.
~~112 The~~119 T he Government Accountability Office notes DOD’s difficulty in developing accurate cost estimates for hypersonic 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.”weapons programs. For example, between FY2019 and FY2020, estimates for CPS “almost doubled.” Government Government
Accountability Office, Accountability Office, Hypersonic Weapons: DOD Should Clarify Roles and Responsibilities to Ensure Coordination
across ~~Development~~Developm ent Efforts, GAO-21-378, March 22, 2021, p. 21, https://www.gao.gov/products/gao-21-378. , GAO-21-378, March 22, 2021, p. 21, https://www.gao.gov/products/gao-21-378.
Congressional Research Service Congressional Research Service

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Hypersonic Weapons: Background and Issues for Congress Strategic Stability 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 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 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 facilities. Some analysts argue that unintended escalation could occur as a result of warhead ambiguity, or from the inability to distinguish between a conventional y armed hypersonic weapon and a nuclear-armed one. However, as a United Nations report notes, “even if a State did know that an HGV launched toward it was conventional y armed, it may stil view such a weapon as strategic in nature, regardless of how it was perceived by the State firing the weapon, and decide that a ~~and Issues for Congress~~

strategic response was warranted.”strategic response was warranted.”~~113~~120 Differences in threat perception and escalation ladders Differences in threat perception and escalation ladders
could thus result in unintended escalation. Such concerns have previously led Congress to restrict could thus result in unintended escalation. Such concerns have previously led Congress to restrict
funding for conventional prompt strike programs.funding for conventional prompt strike programs.~~114~~121
Other analysts have argued that the strategic implications of hypersonic weapons are minimal. Other analysts have argued that the strategic implications of hypersonic weapons are minimal.
Pavel Podvig, a senior research Pavel Podvig, a senior research ~~fellow~~fel ow at the United Nations Institute for Disarmament Research, at the United Nations Institute for Disarmament Research,
has noted that the weapons “don’t … change much in terms of strategic balance and military has noted that the weapons “don’t … change much in terms of strategic balance and military
capability.”capability.”~~115~~122 This, some analysts argue, is because U.S. competitors such as China and Russia This, some analysts argue, is because U.S. competitors such as China and Russia
already possess the ability to strike the Unitedalready possess the ability to strike the United States with intercontinental States with intercontinental ~~ballistic~~bal istic missiles, missiles,
which, when launched in salvos, could overwhelm U.S. missile defenses.which, when launched in salvos, could overwhelm U.S. missile defenses.~~116~~123 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 real y~~is really~~ a stretch to try to imagine any regime in the world that would be so suicidal that it would 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 even think threating to use—not to mention to ~~actually~~actual y use—hypersonic weapons against the use—hypersonic weapons against the
United States ... would end United States ... would end ~~well.”117~~wel .”124
Section 1671 of the FY2021 NDAA Section 1671 of the FY2021 NDAA (P.L. 116-283) directs the Chairman of the Joint Chiefs of (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 How ~~escalation risks will be addressed with regards to the use of strategic~~ escalation risks will be addressed with regards to the use of strategic hypersonic hypersonic
weapons,weapons, including whetherincluding whether ~~any risk escalation exercises have been conducted or~~ any risk escalation exercises have been conducted or are 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~~
~~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~~
~~new multilateral arms control agreements, and undertaking transparency and confidence-building~~
~~measures.118~~
~~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,~~
~~as do hypersonic glide vehicles and hypersonic cruise missiles.119 However, Article V of the treaty~~

~~113~~ 120 United Nations Office of Disarmament Affairs, United Nations Office of Disarmament Affairs, Hypersonic Weapons.
~~114~~121 For a history of legislative activity on conventional prompt global strike, see CRS For a history of legislative activity on conventional prompt global strike, see CRS Report R41464, Report R41464, Conventional
~~Prompt~~Prom pt Global Strike and Long-Range Ballistic Missiles: Background and Issues, by Amy F. Woolf. , by Amy F. Woolf.
~~115~~122 Amy Mackinnon, “Russia’s New Amy Mackinnon, “Russia’s New ~~Missiles~~ Missiles Are Aimed at the U.S.,”Are Aimed at the U.S.,” Foreign Policy, March 5, 2019, , March 5, 2019,
https://foreignpolicy.com/2019/03/05/russias-new-missiles-are-aimed-at-you-weapons-hypersonic-putin-united-states-https://foreignpolicy.com/2019/03/05/russias-new-missiles-are-aimed-at-you-weapons-hypersonic-putin-united-states-
inf/. inf/.
~~116~~123 David Axe, “How the U.S. David Axe, “How the U.S. Is Quietly Winning the Hypersonic Arms Race,”Is Quietly Winning the Hypersonic Arms Race,” The Daily Beast, January 16, 2019, , January 16, 2019,
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.
~~117~~124 Jyri Raitasalo, “Hypersonic Weapons are No Game-Changer,” Jyri Raitasalo, “Hypersonic Weapons are No Game-Changer,” The National Interest, January 5, 2019, , January 5, 2019,
https://nationalinterest.org/blog/buzz/hypersonic-weapons-are-no-game-changer-40632. https://nationalinterest.org/blog/buzz/hypersonic-weapons-are-no-game-changer-40632.
~~118 See United Nations Office of Disarmament Affairs, Hypersonic Weapon; and Richard H. Speier et al.,~~ ~~Hypersonic~~
~~Missile Proliferation.~~
~~119 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,~~
~~“Hypersonic Weapons: Strategic Asset or Tactical Tool?”~~
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Congressional Research Service 20 Hypersonic Weapons: Background and Issues for Congress Arms Control 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 limit the weapons’ proliferation. Proposed measures include expanding New START, negotiating new multilateral arms control agreements, and undertaking transparency and confidence-building measures.125 The New START Treaty, a strategic offensive arms treaty between the United States and Russia, does not currently cover weapons that fly on a bal istic trajectory for less than 50% of their flight, as do hypersonic glide vehicles and hypersonic cruise missiles.126 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 Party ~~shall~~ shal have the right to raise the question of such a strategic offensive arm for consideration have the right to raise the question of such a strategic offensive arm for consideration
in the Bilateralin the Bilateral Consultative Commission (BCC).” Accordingly, some legal experts hold that the 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 United States could raise the issue in the BCC of negotiating to include hypersonic weapons in
the New START limits.the New START limits.~~120~~127 However, because New START is due to expire in 2026, this may be a However, because New START is due to expire in 2026, this may be a
short-term solution.short-term solution.~~121~~
128 As an alternative, some analysts have proposed negotiating a new international As an alternative, some analysts have proposed negotiating a new international arms control arms control
agreement that would institute a moratorium or ban on hypersonic weapon testing. These analysts 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.~~122~~129 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.”~~123~~130 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.”131 125 See United Nations Office of Disarmament Affairs, Hypersonic Weapon; and Richard H. Speier et al., Hypersonic Missile Proliferation. 126 In some cases, hypersonic glide vehicles may be launched from intercontinental ballistic missiles that are already covered by New ST ART , as is reported to be the case with Russia’s Avangard HGV. See Rachel S. Cohen, “Hypersonic Weapons: Strategic Asset or T actical T ool?” 127~~tests.”124~~

~~120~~ James Acton notes: “during [New James Acton notes: “during [New ST ART ~~START~~] negotiations, Russia] negotiations, Russia ~~argued~~ argued that boostthat boost -glide weapons might constitute ‘a -glide weapons might constitute ‘a
newnew kind of strategic offensive arm,’ in which case they wouldkind of strategic offensive arm,’ in which case they would trigger bilateral discussionstrigger bilateral discussions about whether and how about whether and how
they wouldthey would be be regulated by the treaty—a position [then] rejected by the United States.” James M. Acton, regulated by the treaty—a position [then] rejected by the United States.” James M. Acton, Silver Bullet?:
Asking the Right Questions about Conventional ~~Prompt~~Prom pt Global Strike, Carnegie Endowment for International Peace, , Carnegie Endowment for International Peace,
2013, p. 139, https://carnegieendowment.org/files/cpgs.pdf. 2013, p. 139, https://carnegieendowment.org/files/cpgs.pdf.
~~121~~128 CRS CRS Report R41219, Report R41219, The New START Treaty: Central Limits and Key Provisions, by Amy F. Woolf. , by Amy F. Woolf.
~~122~~129 Mark Gubrud, Mark Gubrud, ~~“Test~~ “T est Ban for Hypersonic Missiles?” Bulletin of the Atomic Scientists, August Ban for Hypersonic Missiles?” Bulletin of the Atomic Scientists, August 6, 2015, 6, 2015,
https://thebulletin.org/roundtable/test-ban-for-hypersonic-missiles/. https://thebulletin.org/roundtable/test-ban-for-hypersonic-missiles/.
~~123 Tong~~130 T ong Zhao, “ Zhao, “~~Test~~T est Ban for Hypersonic Missiles?” Ban for Hypersonic Missiles?”
~~124~~131 Rajaram Nagappa, “ Rajaram Nagappa, “~~Test~~T est Ban for Hypersonic Missiles?”; see Ban for Hypersonic Missiles?”; see also James M. Acton, also James M. Acton, Silver Bullet?, pp. 134-138. , pp. 134-138.
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Appendix. U.S. Hypersonic Testing ~~Infrastructure125~~Infrastructure132
Table A-1. DOD Hypersonic Ground Test Facilities
Facility
Capability
Location
Air Air Force Arnold Engineering and 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, Arnold AFB, TN TN
Development Development Complex (AEDC) von Complex (AEDC) von
to 290 °F to 290 °F
Karman Gas Dynamics Karman Gas Dynamics Facility 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 Air Force AEDC High-Enthalpy Force AEDC High-Enthalpy
Simulate thermal Simulate thermal and pressure and pressure
Arnold AFB, Arnold AFB, TN TN
Aerothermal Aerothermal Test Arc-Heated Test Arc-Heated
environments environments at speeds of up to at speeds of up to
Facilities Facilities H1, H2, H3 H1, H2, H3
Mach 8 Mach 8
Air Air Force AEDC Tunnel 9 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 Air Force AEDC Aerodynamic and Force AEDC Aerodynamic and
Mach 3.1-7.2; up to 1300 °F Mach 3.1-7.2; up to 1300 °F
Arnold AFB, Arnold AFB, TN TN
Propulsion Test Unit Propulsion Test Unit
Air Air Force AEDC Force AEDC ~~Aeroballistic~~ Aerobal istic Range Range
Launches projectiles Launches projectiles of up to 8 of up to 8
Arnold AFB, Arnold AFB, TN TN
G G
inches in diameter at speeds of up inches in diameter at speeds of up
to Mach 20 to Mach 20
~~Holloman~~ Hol oman High Speed Test Track High Speed Test Track
59,971 ft. track; launches 59,971 ft. track; launches
~~Holloman~~ Hol oman AFB, NM AFB, NM
projectiles projectiles at speeds of up to Mach at speeds of up to Mach
8 8
Air Air Force Research Laboratory Force Research Laboratory
Mach 3-7 Mach 3-7
Wright-Patterson AFB, OH Wright-Patterson AFB, OH
(AFRL) (AFRL) ~~Cells~~ Cel s 18, 22 18, 22
AFRL Laser AFRL Laser Hardened Materials Hardened Materials
High-temperature materials High-temperature materials testing 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 Test Resource Management Center Management Center
Up to Mach 8; up to 4040 °F Up to Mach 8; up to 4040 °F
Arnold AFB, Arnold AFB, TN TN
Hypersonic Aeropropulsion Hypersonic Aeropropulsion Clean Clean
AirAir Test-bed Facility Test-bed Facility
Source: (U//FOUO) Paul F. Piscopo et al. Air Force (U//FOUO) Paul F. Piscopo et al. Air Force AEDC Tunnel 9 was upgraded in 2019 to enable Mach 18 AEDC Tunnel 9 was upgraded in 2019 to enable Mach 18
testing. See “Department of Defense Presstesting. See “Department of Defense Press Briefing on Hypersonics,”Briefing on Hypersonics,” March 2, 2020, https://www.defense.gov/March 2, 2020, 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/.

~~125 The~~ 132 T he following information is derived from the 2014 report (U//FOUO) Paul F. Piscopo et al., 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 Sciencehas been granted by the Office of Science ~~and Technology Policy.~~
and T echnology Policy. Congressional Research Service Congressional Research Service

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Table A-2. DOD Open-Air Ranges
Range
Location
Ronald Reagan Ronald Reagan ~~Ballistic~~ Bal istic Missile Missile
Kwajalein Kwajalein ~~Atoll,~~ Atol , Republic of the Republic of the
Defense Test Site Defense Test Site
~~Marshall~~ Marshal Islands Islands
Pacific Missile Pacific Missile Range Facility (PMRF) Range Facility (PMRF)
Kauai, HI Kauai, HI
Western Western Range, 30th Space Wing Range, 30th Space Wing
Vandenberg AFB, Vandenberg AFB, CA CA
Naval Air Warfare Naval Air Warfare Center Weapons Center Weapons
Point Mugu and China Lake, Point Mugu and China Lake, CA CA
(NAWC) Division (NAWC) Division
White Sands Missile White Sands Missile Range (WSMR) Range (WSMR)
New Mexico New Mexico
Eastern Range, 45th Space Wing Eastern Range, 45th Space Wing
Cape Canaveral Air Cape Canaveral Air Force Force
Station/Patrick AFB/Kennedy Station/Patrick AFB/Kennedy
Space Center, FL Space Center, FL
NASA NASA ~~Wallops~~ Wal ops Flight Facility Flight Facility
~~Wallops~~ Wal ops Island, VA 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 NAWC Weapons Division R-2508 R-2508
Edwards AFB, Edwards AFB, CA 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 PMRF Mobile At-sea Sensor System System
MDA Mobile Instrumentation MDA Mobile Instrumentation
System System Pacific ~~Collector~~ Col ector
MDA Mobile Instrumentation MDA Mobile Instrumentation
System System Pacific Tracker
Kwajalein Kwajalein Mobile Range Safety Mobile Range Safety
System 2 System 2
United States Navy Ship United States Navy Ship Lorenzen
missilemissile range instrumentation ship 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 Transportable Telemetry System 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 Ames Research Center (ARC) High-temperature Research Center (ARC) High-temperature

Mountain View, CA Mountain View, CA
Arc Jet Complex Arc Jet Complex
materials materials testing testing
ARC Hypervelocity ARC Hypervelocity Free Free
Launches projectiles Launches projectiles at 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 LaRC Scramjet Test Complex 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 Mach 5, 6, and 7 and up to
Sandusky, OH Sandusky, OH
(GRC) Plumbrook (GRC) Plumbrook ~~Hypersonic~~ Hypersonic 3830 °F 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 discrete airspeeds) and up 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 Sandia National Laboratories Solar Solar
High-temperature materials High-temperature materials testing 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: AtmosphericLENS XX: Atmospheric ~~re-entry~~ reentry
simulation simulation
~~ATK-GASL Test Bay 4~~

Boeing Polysonic Wind TunnelBoeing Polysonic Wind Tunnel
48-inch up to Mach 5 48-inch up to Mach 5
St. Louis, St. Louis, MO
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~~Hypersonic Weapons: Background and Issues for Congress~~
MO
Lockheed Martin High Speed Wind Lockheed Martin High Speed Wind
48-inch Mach .3-5 48-inch Mach .3-5
~~Dallas,~~ Dal as, TX TX
Tunnel Tunnel
Boeing/Air Boeing/Air Force Office of ScientificForce Office of Scientific 9.5-inch Mach 6 9.5-inch Mach 6
West Lafayette, IN West Lafayette, IN
Research (AFOSR) Quiet Tunnel at Research (AFOSR) Quiet Tunnel at
Purdue UniversityPurdue University Congressional Research Service 24 Hypersonic Weapons: Background and Issues for Congress AFOSR-University
~~AFOSR-University~~ of Notre Dame of Notre Dame
24-inch Mach 6 24-inch Mach 6
Notre Dame, Notre Dame, IN Quiet Tunnel Stratolaunch Carrier Aircraft Reusable Mach 6 test bed N/AIN
~~Quiet Tunnel~~
Sources: (U//FOUO) Paul F. Piscopo et al.; Oriana Pawlyk, “Air Force (U//FOUO) Paul F. Piscopo et al.; Oriana Pawlyk, “Air Force Expanding Hypersonic Technology Expanding Hypersonic Technology
Testing”; University of Arizona,Testing”; University of Arizona, “Mach 5 Quiet Ludwieg Tube”; and Ashley Tressel,“Mach 5 Quiet Ludwieg Tube”; and Ashley Tressel, “Army“Army to open hypersonic to open hypersonic
testing facility.” testing facility.”
Notes: Hypersonic wind tunnels are under construction at the Hypersonic wind tunnels are under construction at the ~~following~~ fol owing universities:universities: Texas A&M University Texas A&M University
(Mach 10 quiet tunnel expected to be complete(Mach 10 quiet tunnel expected to be complete in 2021), the Universityin 2021), the University of Arizona (Mach 5 quiet tunnel of Arizona (Mach 5 quiet tunnel
expected to be completeexpected to be complete in 2021), Purdue Universityin 2021), Purdue University (Mach 8 quiet tunnel expected to be complete(Mach 8 quiet tunnel expected to be complete in 2022), in 2022),
and the Universityand the University of Notre Dameof Notre Dame (Mach 10 quiet tunnel expected to be complete in 2023). Additional (Mach 10 quiet tunnel expected to be complete in 2023). Additional
universities,universities, such as the University of Maryland, the California Institute of Technology, the Georgia Institute of such as the University of Maryland, the California Institute of Technology, the Georgia Institute of
Technology, the AirTechnology, the Air Force Academy,Force Academy, the University of Tennesseethe University of Tennessee Space Institute, and Virginia Polytechnic Space Institute, and Virginia Polytechnic
Institute and State University,Institute and State University, also maintain experimentalalso maintain experimental hypersonic facilitieshypersonic facilities or conduct hypersonic research. 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
This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan
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