Defense Primer: Directed-Energy Weapons




November 23, 2021
Defense Primer: Directed-Energy Weapons
Both the 2018 National Defense Strategy and the House
U.S. Department of State personnel stationed abroad. While
Armed Services Committee’s bipartisan Future of Defense
a National Academies of Sciences (NAS) consensus study
Task Force Report have identified directed energy as a
report concluded that an HPM weapon provided the “most
technology that could have a significant impact on U.S.
plausible” explanation of these symptoms from those
national security in the years to come. As the Department of
studied, the NAS committee noted that it “cannot rule out
Defense (DOD) continues to invest in directed-energy (DE)
other possible mechanisms.” The U.S. government has
weapons, Congress may consider implications for defense
neither identified the source of the symptoms nor attributed
authorizations, appropriations, and oversight.
them to the actions of any particular government or
organization.
Overview
DOD defines DE weapons as those using concentrated
Directed-Energy Weapons Programs
electromagnetic energy, rather than kinetic energy, to
A number of countries are investing in directed-energy
“incapacitate, damage, disable, or destroy enemy
weapons programs. This In Focus discusses a selection of
equipment, facilities, and/or personnel.” DE weapons
unclassified DE weapons programs in three leading military
include high-energy lasers (HEL) and high-powered
powers: the United States, China, and Russia.
microwave (HPM) weapons; other DE weapons, such as
particle beam weapons, are outside the scope of this In
United States
Focus.
The DOD has a number of DE development programs
underway, requesting at least $578 million in FY2022 for
HELs might be used by ground forces in short-range air
unclassified DE research, development, test, and evaluation
defense (SHORAD), counter-unmanned aircraft systems
(RDT&E) and at least $331 million for unclassified DE
(C-UAS), or counter-rocket, artillery, and mortar (C-RAM)
weapons procurement. For additional information about
missions. The weapons might be used to “dazzle” (i.e.,
specific U.S. DE weapons programs, see CRS Report
temporarily disable) or damage satellites and sensors. This
R44175, Navy Lasers, Railgun, and Gun-Launched Guided
could in turn interfere with intelligence-gathering
Projectile: Background and Issues for Congress, by Ronald
operations; military communications; and positioning,
O'Rourke, and CRS Report R45098, U.S. Army Weapons-
navigation, and timing systems used for weapons targeting.
Related Directed Energy (DE) Programs: Background and
In addition, HELs could theoretically provide options for
Potential Issues for Congress, by Andrew Feickert.
boost-phase missile intercept, given their speed-of-light
travel time; however, experts disagree on the affordability,
Many of these programs are intended to support the Office
technological feasibility, and utility of this application.
of the Under Secretary of Defense for Research and
Engineering’s (OUSD[R&E]) Directed Energy Roadmap.
In general, HELs might offer lower costs per shot and—
According to a presentation in 2020 by DOD Principal
assuming access to a sufficient power supply—deeper
Director for Directed Energy Dr. Jim Trebes, who leads the
magazines compared with traditional munitions. (Although
department’s DE efforts, the roadmap articulates DOD’s
a number of different types of HELs exist, many of the
objective of “[achieving] dominance in DE military
United States’ current programs are solid state lasers, which
applications in every mission and domain where they give
are fueled by electrical power. As a result, the cost per shot
advantage.” The roadmap additionally outlines DOD’s plan
is equivalent to the cost of the electrical power required to
to increase power levels of DE weapons from around 150
fire the shot.) This could in turn produce a favorable cost-
kilowatts (kW—a unit of power), as is currently feasible, to
exchange ratio for the defender, whose marginal costs
around 300 kW by FY2022, 500 kW by FY2024, and 1
would be significantly lower than those of the aggressor.
megawatt (MW) by FY2030. For reference, although there
is no consensus regarding the precise power level that
Similarly, HPM weapons could provide a nonkinetic means
would be needed to neutralize different target sets, some
of disabling adversary electronics and communications
analysts believe that lasers of around 100 kW could engage
systems. These weapons could potentially generate effects
unmanned aircraft systems, small boats, rockets, artillery,
over wider areas than HELs, which emit a narrower beam
and mortars, whereas lasers of around 300 kW could
of energy. As a result, some analysts have noted that HPM
additionally engage cruise missiles flying in certain profiles
weapons might provide more effective area defense against
(i.e., flying across—rather than at—the laser). Lasers of 1
missile salvos and swarms of drones.
MW could potentially neutralize ballistic missiles and
hypersonic weapons.
In addition, some reports posit that an HPM weapon might
be responsible for Havana Syndrome—the term used by
In addition to the DE roadmap, OUSD(R&E) manages the
some to describe a collection of symptoms experienced by
High Energy Laser Scaling Initiative (HELSI), which
https://crsreports.congress.gov

Defense Primer: Directed-Energy Weapons
Principal Director Trebes notes is “to demonstrate laser
technology maturation efforts reducing the SWaP and
output power scaling while maintaining or improving beam
cooling requirements of DE systems?
quality and efficiency.” HELSI is intended to strengthen the
defense industrial base for potential future directed energy
Weapons Characteristics
weapons by providing near-term prototyping opportunities
Although HELs may offer a lower cost per shot than
for industry partners. Dr. Trebes additionally notes that
traditional weapons such as missiles, they are also subject
OUSD(R&E) has completed a DOD-wide Laser Lethality
to a number of limitations. For example, atmospheric
Analysis Process Review to identify future needs for the
conditions (e.g., rain, fog, obscurants) and SWaP and
Department and best practices for DE development and use
cooling requirements can limit the range and beam quality
and plans to establish a Directed Energy Lethality Database
of HELs, in turn reducing their effectiveness. Traditional
that is to serve as a searchable repository for DOD’s DE
weapons, in contrast, are not affected by these factors.
analyses.
How, if at all, might HEL limitations be mitigated by
technological developments, concepts of operation, or other
China
methods? What impact might a failure to mitigate these
According to the US-China Economic and Security Review
limitations have on future military operations?
Commission, China has been developing DE weapons since
at least the 1980s and has made steady progress in
Mission Utility
developing HPM and increasingly powerful HELs. China
Given the strengths and weaknesses of DE weapons, DOD
has reportedly developed a 30-kilowatt road-mobile HEL,
is continuing to examine their role within the military. DOD
LW-30, designed to engage unmanned aircraft systems and
is additionally conducting multiple utility studies to analyze
precision-guided weapons. Reports indicate that China is
potential concepts of operation for DE weapons and to
also developing an airborne HEL pod.
assess the scenarios in which they might be militarily
useful. How might Congress draw upon the conclusions of
According to the Defense Intelligence Agency, China is
these analyses as it conducts oversight of DE weapons
additionally pursuing DE weapons
programs? What is the appropriate balance between DE
weapons and traditional munitions within the military’s
to disrupt, degrade, or damage satellites and their
portfolio of capabilities?
sensors and possibly already has a limited
capability to employ laser systems against satellite
Defense Industrial Base
sensors. China [has likely fielded] a ground-based
Some analysts have expressed concerns that, in the past,
laser weapon that can counter low-orbit space-
DOD did not provide stable funding for DE weapons
based sensors ... and by the mid-to-late 2020s, it
programs or sufficient opportunities for the DE workforce.
may field higher power systems that extend the
According to OUSD(R&E), HELSI is intended to address
threat to the structures of non-optical satellites.
these concerns by providing industry with assured
prototyping opportunities. In what ways, if any, has HELSI
Russia
strengthened the defense industrial base for DE weapons?
Russia has been conducting DE weapons research since the
What, if any, challenges does the base continue to face and
1960s, with a particular emphasis on HELs. Russia has
how might they be mitigated?
reportedly deployed the Peresvet ground-based HEL with
Intelligence Requirements
several mobile intercontinental ballistic missile units.
Although little is publicly known about Peresvet, including
Some analysts have questioned whether DOD has sufficient
its power level, some analysts assert it is to dazzle satellites
knowledge of adversary DE weapons systems and materials
and provide point defense against unmanned aircraft
to develop its weapons requirements. DOD is currently
systems. Russia’s deputy defense minister Alexei
attempting to further define its DE collection requirements
Krivoruchko has stated that efforts are underway to increase
for the intelligence community (IC) through the Directed
Peresvet’s power level and to deploy it on military aircraft.
Energy Lethality Intelligence initiative. To what extent, if at
Reports suggest that Russia may also be developing HPMs
all, is this initiative improving connectivity between DOD’s
as well as additional HELs capable of performing anti-
DE community and the IC? What collection requirements,
satellite missions.
if any, remain?
Potential Issues and Questions for
Coordination within DOD
Congress
Pursuant to Section 219 of the FY2017 National Defense
Authorization Act (P.L. 114-328), OUSD(R&E)’s Principal
Technological Maturity
Director for directed energy is tasked with coordinating DE
Directed-energy weapons programs continue to face
efforts across DOD and with developing DOD’s Directed
questions about their technological maturity, including the
Energy Roadmap, which is to guide development efforts.
ability to improve beam quality and control to militarily
To what extent are the military departments and defense
useful levels and the ability to meet size, weight, and power
agencies adhering to this roadmap? What, if any, additional
(SWaP) and cooling requirements for integration into
authorities or structural changes would be required to
current platforms. Some DE systems are small enough to fit
ensure proper coordination throughout DOD?
on military vehicles, but many require larger and/or fixed
platforms that could potentially limit deployment options
Kelley M. Sayler, Analyst in Advanced Technology and
and operational utility. In what ways, if any, are DOD
Global Security
https://crsreports.congress.gov

Defense Primer: Directed-Energy Weapons

IF11882
John R. Hoehn, Analyst in Military Capabilities and
Programs


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