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Luftfahrt - Background zu US-NAVY - UAV-Laser-Abschuß-Teil2

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The MLD successfully burned through sections of
small boats during static, ground-based firing tests in September 2010, and
was mounted on the Navy’s Self Defense Test Ship in April and May 2011 for
a sea-based demonstration. The MLD package for the latter test used a single
15-kilowatt SSL chain from OSD’s JHPSSL program that was tied into the ship’s
power and radar systems.56
The Navy has also funded two additional SSL concepts. The first concept was
designed to explore the potential of a tactical SSL to counter “multiple surface and
air threats … such as small boats and UAVs” in various sea states.57 Work continues
to integrate this Tactical Laser System (TLS) with the Mk 38 Machine Gun System.
The second SSL concept would integrate a 25-kilowatt fiber SSL onboard an H-60
helicopter to engage surface targets from the air.
The U.S. Navy could field an operational, ship-based laser weapon by 2018
based on technologies demonstrated by the LaWS and MLD programs, both of
which achieved Technology Readiness Levels (TRL) between 5 and 6 (i.e., model
or prototype demonstrated in a relevant environment). Surface ships are particularly
well-suited to support the size, weight, power, and cooling requirements of
current-technology SSLs. Flight III of the Arleigh Burke-class of guided missile
destroyers (DDGs), for example, will have the potential to generate enough excess
power and cooling to support a JHPSSL-derivative slab laser system with an output
of 100–200 kilowatts (see Figure 6).
Fitting Arleigh Burke-class DDGs and other surface ships with SSLs could provide
the Navy with a globally deployable network for countering attacks by surface
craft, UAVs, and possibly ASCMs, especially if the SSLs are used in conjunction
with tactics that enable side-shot engagements against incoming missile
threats.59 Moreover, ship-based SSLs could be fi red almost continuously, assuming
their power supplies and cooling are not interrupted.
Although both the LaWS and MLD demonstrator programs exhausted their
funding in fi scal year (FY) 2011, the Navy may soon commit to providing the
resources necessary to operationalize an SSL for maritime defense. Given adequate
resources, the Navy could become the fi rst Service to fi eld a high-power
DE capability that could be the harbinger of a discontinuous shift in the military
competition between guided munitions and the systems designed to defend
against them.
Lasers to Defend High-Value Theater Bases
In the near term, it may be feasible to exploit mature technologies to field a
ground-based laser weapon capable of defending forward operating locations
against air and missile threats. If employed in combination with a relay mirror
system, the range and target set of ground-based lasers could be increased
significantly to counter cruise missiles and irregular forces preparing to launch
G-RAMM. While the precise energy needed to defeat ballistic missiles is not
known, sources suggest that a laser with an output in the multi-megawatt range
would be needed.60 Although it is highly unlikely that a multi-megawatt laser
weapon system would be ground mobile in the near term, they could be packaged
into transport containers that would be deployable by air or sea to protect
high-value facilities such as forward airfields and ports. As mentioned previously,
DE air and missile defense systems would not obviate the need for kinetic
weapons such as the Army’s THAAD, PAC-3, and Avenger systems. They could,
however, increase the overall effectiveness of air and missile defense networks as
well as reduce an enemy’s confidence that its attacks would succeed.61
The technologies to support a ground-based laser defense are very mature.
With adequate resources, DoD could deploy an initial multi-megawatt system
in a few years using technologies demonstrated by the ABL program.62 The Air
Force continues to fund a research effort to advance COIL technologies for future
military applications. The Air Force Research Laboratory (AFRL) is making
progress toward developing smaller COIL modules that generate a megawatt of
power at 50 to 60 percent efficiency. AFRL is also exploring methods to recycle
the chemicals used as lasing media by COILs, which could reduce the logistics requirements
of a deployed chemical laser weapon. The Air Force could incorporate
these smaller, more powerful COILs into deployable systems for ground-based
air and missile defense within the next five to ten years.63
Ground-based missile defenses using SSLs may eventually be feasible.64
JHPSSL-based developmental systems may be the most mature concepts, having
demonstrated power levels in excess of 100 kilowatts. Further investments could
enable scaling of this technology to several hundred kilowatts or potentially well
over a megawatt. DARPA’s HELLADS could also be scaled to higher powers if it
realizes its initial 150-kilowatt power objective.
Counter-Electronics High Power Microwa ve
Advanced Missile Project
The Counter-Electronics High Power Microwave Advanced Missile Project Joint
Capability Technology Demonstration (CHAMP JCTD), initiated by the Air Force
in 2009, is developing an HPM package capable of “degrading, damaging, or destroying
electronic systems” that could be carried by small airborne platforms
such as cruise missiles or UAVs.65 The JCTD’s objective is to develop several aerial
test vehicles carrying HPM weapons and assess their performance.
Assuming the JCTD meets its objectives, it may be possible to field cruise
missiles and low-observable UAVs with HPM payloads in the very near future.66
These weapons could allow commanders to conduct multiple strikes per sortie
against the electronic systems that underpin A2/AD complexes, such as command
and control networks, target acquisition radars, and surface-to-air missile
sites. The follow-on development of an HPM weapon carried by a penetrating
UAV could result in a more powerful, recoverable system that could create effects
over longer ranges and strike far more targets per mission than smaller cruise
missile HPM packages.
Tac tical Relay Mirors
Tactical relay mirror concepts typically use two beam director telescopes and
beam control optics to receive a laser beam from a remote source, “clean up”
the beam, and transmit it to targets beyond the line of sight of the source laser
weapon. A relay mirror could be mounted on a UAV or suspended from an aerostat
to significantly extend the range of airborne and surface-fired laser weapons.
Tactical relays would be most appropriate to direct lethal laser energy over short
ranges (up to a few tens of kilometers) onto targets in coastal, maritime, and urban
areas. These systems could also provide persistent, extremely high-resolution imagery
of areas within their field of view when not relaying laser beams, permitting
them to be used to find, identify, fix, and track targets at significantly extended
ranges. A UAV-based relay mirror system could launch from aircraft carriers to
enable ship-based SSLs to achieve side shots against ASCMs (a cruise missile’s
body is a much softer target than its nosecone), and an aerostat-based relay mirror
could enable beyond-line-of-sight attacks on G-RAMM and their launch sites.
In 2006, the U.S. Air Force and Office of Force Transformation provided $40
million to develop a Tactical Relay Mirror System (TRMS) technology demonstrator.
68 Outdoor tests of the prototype system suspended by a crane (see Figure
7) were completed successfully.69 It is uncertain if the Air Force or another Service
will continue to fund the follow-on development of an operational TRMS.70
Electric Laser on a Large Aircraft (ELLA)
The U.S. Air Force is developing technologies that could enable the installation of
high-energy SSLs on large aircraft. The operational implications of such a weapon
are potentially game-changing.71 For example, a HEL-equipped, penetrating
bomber could, in addition to defending itself against air-to-air and surface-to-air
threats, strike a variety of ground targets without the need to expend conventional
guided weapons. ELLA could also enhance the survivability of air refueling tankers
and large command, control, and surveillance aircraft, allowing them to operate
closer to hostile airspace to support combat aircraft. It may also be possible
for future HEL-equipped air refueling tankers to provide an additional defensive
combat air patrol layer for friendly aircraft within the range of their laser weapons,
thereby freeing some fighters for other missions.
The Air Force could integrate a 150-kilowatt SSL in the front bomb bay of a
B-1B bomber within the next five or six years to test the practicality of this concept.
72 Given the current state of SSL technologies, though, it may not be possible
to develop an SSL with an affordable unit cost in the near term that would have
sufficient range and power for counter-air missions. With continued funding,
however, it may be possible to develop SSL modules that are better suited for
both large aircraft in the near term and small aircraft in the medium term. Thus,
the Air Force should design future combat aircraft, including the Long-Range
Strike Bomber, UAVs, and eventually a next-generation fighter, with the potential
to accept a laser weapon.
Ground-Mobile High-Energy Lasers
The Army has long desired a mobile HEL capable of defending on-the-move ground
forces against rockets, artillery rounds, and mortars. While fixed-site DE systems
could be deployed to defend large theater bases as previously discussed, a mobile
system could provide a defense against G-RAMM attacks for maneuver forces and
smaller forward operating locations.
Toward this end, the Army began developing the THEL demonstrator in 1996. The
Army cancelled THEL development in 2005 because its large footprint made it unfeasible
as a mobile weapon system. In 2009, the Army initiated the HEL Technology
Demonstrator (HEL TD) program to develop SSL technologies that could lead to
a truly mobile laser weapon with an output of at least a few hundred kilowatts to
counter G-RAMM threats. HEL TD is developing a compact SSL system with beam
control, electrical power supply, thermal management and command, control, and
communications elements integrated into a Heavy Expanded Mobility Tactical Truck
(HEMTT) with a towed trailer. Although the Army is tentatively planning to develop
a mobile HEL by 2018, it has not funded an acquisition program.73
The U.S. Marine Corps is also pursuing a future ground-mobile system to replace
its legacy kinetic Ground Based Air Defense System (GBADS). The replacement
weapon should be capable of countering “Unmanned Aircraft Systems (UAS) with a
secondary capability against cruise missiles (CM), manned rotary wing (RW),
and fixed wing (FW) aircraft.”74 It is likely that the Marine Corps will assess
the feasibility of various SSL technologies as future GBADS weapons during a
counter-UAS exercise planned for FY 2012.
Gunship Laser Weapon System
The Air Force Special Operations Command (AFSOC) has expressed a desire
for an airborne laser weapon capable of covertly attacking ground targets with
great precision over extended ranges. A future gunship aircraft with a suitable
laser system may be capable of striking high-value targets with little risk of unwanted
collateral damage, a novel capability that would be especially important
during operations in urban terrain against irregular forces.
The Advanced Tactical Laser (ATL) Advanced Concept Technology
Demonstration (ACTD) was initiated in 2006 to explore the potential of such
a capability. The ACTD installed a COIL on a C-130 and successfully engaged
representative targets on the ground (see Figure 8).75 Because of the ATL
COIL’s size and weight, AFSOC abandoned the concept in favor of exploring
the feasibility of replacing one of the AC-130’s 20- or 30-millimeter guns with
a solid-state laser. Concerns remain over such a system’s unit cost and potential
to jeopardize other AFSOC modernization priorities, including its plan to
recapitalize the aging gunship fl eet with new AC-130J aircraft.
NoN-LEtHAL WEAPoNs
Promising non-lethal DE capabilities that could be transitioned in the near term
to protect U.S. forces and forward operating bases include radio frequency-based
vehicle and vessel stoppers, and an Active Denial System (ADS) that is capable
of projecting beams of non-lethal, millimeter-wave energy over tactically relevant
ranges to deter hostile acts against U.S. personnel.
A DoD JCTD developed two demonstrator ADS vehicles. The fi rst ADS
prototype was mounted on a High Mobility Multipurpose Wheeled Vehicle
(HMMWV) to demonstrate its tactical mobility. ADS version 2 (see Figure 9)
was built without size and packaging constraints to provide system hardening
against small arms. Both systems underwent extensive testing and demonstrated
their ability to create desired non-lethal effects during thousands of
“full body shots ... with no personnel injuries.”76 Revised designs could project
a smaller beam spot on targets at ranges more desired by warfi ghters. They
could also incorporate newer technologies so they can be mounted on smaller
vehicles to enhance force protection and support missions such as humanitarian
operations and non-combatant evacuations that could require non-lethal
capabilities.
In FY 2011, DoD invested approximately $25 million in non-lethal DE weapon
technologies, the vast majority of which was provided by the Joint Non-Lethal
Weapons Directorate. While the directorate relies on the Services to transition and
field promising major non-lethal DE capabilities such as the ADS and vehicle and
vessel stoppers, the Services have not programmed resources for this purpose.
Kilowa tt-Class Laser Infrared Countermeasures
Multiple Services are in the process of integrating a variety of laser infrared countermeasure
systems on military aircraft. Current systems use very low-power
pulsed lasers (a few watts) to “jam” or confuse MANPADS guided by infrared
seekers. Low-power laser systems such as the LAIRCM and its derivatives may,
however, have little effect on advanced MANPADS and air-to-air missiles that
use imaging infrared (IIR) seekers and/or multiple seeker systems (e.g., multiple-
band IIR, ultraviolet sensors, and passive radar seekers used in conjunction
with surface or airborne radars). Using current technology, it should be possible
to integrate a kilowatt-class SSL on larger aircraft that could burn out the guidance
systems of these more advanced threats.
the ne xt ten to twenty years
Ship-Based Fre Electron Laser
A future multi-megawatt-class FEL could provide the Navy with a new ship-based
capability to engage ASCMs, ballistic missiles, and other airborne threats to surface
forces. Ship-based FELs could also be used to defend forward bases located
in littoral regions. The Navy’s current FEL demonstrator program supports these
objectives.
Despite continuing technological advances, it may not be possible to demonstrate
an operationally feasible megawatt-class FEL until the mid-2020s or later.
Megawatt-class FEL devices will likely remain quite large—potentially spanning
multiple bulkheads in current ships—and thus may require new hull designs to
accommodate them. Other barriers to creating operational megawatt-class FELs
include the massive shielding that would be needed to protect personnel and electronics
from the radiation produced by the collisions of stray near-relativistic
electrons escaping from the FEL accelerator racetrack,77 and the challenge of
dealing with the waste heat generated by FELs even if they were capable of operating
at 5 to 10 percent efficiency.
Electric Laser on a Smal Aircraft (ELSA)
The Air Force is interested in developing a fighter-based laser for counter-air
missions. A HEL-equipped fighter could defeat air-to-air and surface-to-air
missiles launched against it, and greatly extend the fighter’s ability to persist in
opposed airspace. An ELSA with an output of approximately 200 kilowatts could
also prove useful for strikes against soft ground targets.
To be effective, a HEL in a fighter-sized manned or unmanned platform would
need to “generate around 5 kilowatts per kilogram [of the laser system’s total
weight] which means the technology ‘has to be reduced in size and weight by a
factor of ten over the current ground-based system.’”78 Given ELSA’s potential as
a game-changing force multiplier, investments needed to achieve these technological
objectives should be a high priority for DoD.
Strategic Relay Miror System
The Air Force has explored concepts for mounting relay mirrors on large airships
flying at very high altitudes. Strategic relay mirrors carried by airships
or high-altitude, long-endurance (HALE) UAVs could enable ground-based or
sea-based laser systems to interdict missiles, aircraft, and ground targets across
very long ranges.79 A future strategic relay mirror system could leverage DARPA’s
Integrated Sensor Is the Structure (ISIS) program, which seeks to develop a very
large radar array on an airship that would be able to “detect and track extremely
small cruise missiles and unmanned aerial vehicles that are up to 600 kilometers
away, dismounted soldiers that are up to 300 kilometers away, and small
vehicles under foliage up to 300 kilometers away.”80 DoD is not actively pursuing
this concept.
summary
Directed-energy systems have a reputation as perennial weapons of the future—
always showing promise, but technologically out of reach. Today, however, the
U.S. military could transition a number of DE technologies to actual battlefield
capabilities within five to ten years. Since many of the concepts discussed in this
chapter capitalize on decades of S&T investments, DoD should be able to develop
and acquire them at lower cost than new “clean sheet” designs. Within the next
five to ten years, this includes SSL weapons mounted on surface ships, upgraded
COIL modules to defend forward bases, and HPM packages integrated onto penetrating
air vehicles. As technological advances continue to reduce the volume,
weight, and cooling requirements of high-power laser systems, it may be possible
to integrate them on smaller aircraft and tactical ground vehicles.
Of course, none of the concepts assessed in this chapter will become reality
without adequate resources and the support of senior defense leaders who appreciate
their game-changing potential in future power-projection operations. It
is unlikely that this support will be forthcoming absent an understanding of how
DE systems could address future operational needs in a cost-effective manner.
The following chapter outlines two plausible scenarios in which DE systems could
enable U.S. operations while imposing costs on potential adversaries.
.
To assess how DE capabilities could create new advantages for the U.S. military,
Chapter Four examines two notional scenarios that occur ten to fifteen years in
the future. In the first scenario, a rogue regional power employs A2/AD weapon
systems, including maritime exclusion capabilities, irregular proxy groups
equipped with G-RAMM, and ballistic missiles, in a coercive campaign to prevent
a U.S. crisis response force from gaining access to the Persian Gulf. The
second scenario explores an illustrative AirSea Battle operation against a highly
capable A2/AD battle network in the Western Pacific.
In both scenarios, this report assumes the United States will be among the
first to operationalize high-power DE weapon systems. As with most innovations
in military technologies, however, it should likewise be assumed that other
states and non-state actors will gain access to similar capabilities.81 Therefore,
it will be important for the U.S. military to assess the potential of new DE capabilities
in a range of scenarios, including cases where enemies have developed
similar systems.
supporting operations in the persian gulf
An Illustrative Scenario
Over the next ten to fifteen years, it is likely that Iran will continue to acquire
capabilities that will enable the Iranian military and the Iranian Revolutionary
Guard Corps to contest the ability of foreign forces to operate in the Persian Gulf.
The following scenario illustrates how Iran might execute an A2/AD strategy in
a notional conflict in the 2030 time frame. The scenario assumes that Iran begins
hostilities without warning, and that deployed U.S. forces remain reliant on
bases in the Persian Gulf region.
Ambush U.S. Naval Forces in the Persian Gulf
Iran could exploit the element of surprise to launch a concentrated, combined-arms
attack against U.S. forces operating in the Persian Gulf. Using the narrow and
congested waters of the Gulf and Strait of Hormuz to its advantage, Iran could
launch multiple UAV and small boat swarm attacks in an attempt to overwhelm
the U.S. Navy’s kinetic defenses, such as the AEGIS missile defense system,
Close-In Weapons System (CIWS), and Rolling Airframe Missile. Iran could augment
these attacks with “civilian” vessels equipped with Klub-K missiles stored
surreptitiously in shipping containers and shore batteries capable of launching
salvos of ASCMs.
Attack Regional Bases
In concert with its maritime exclusion operations, Iran could strike U.S. airfields,
logistics bases, and ports using short- and medium-range ballistic missiles
(SRBMs). By opening its barrage with salvos of older “dumb” missiles, Iran
could seek to force the United States to expend large numbers of its kinetic missile
interceptors, thereby opening the door for strikes by newer, precision-guided
missiles. Iranian-sponsored proxy groups could augment Iran’s conventional
missile offensive by attacking U.S. bases and critical regional infrastructure
using pre-sighted G-RAMM.82
Conduct a Coercive Missile Campaign
Although Iran’s large ballistic missile arsenal may lack the accuracy needed to
execute a fully effective conventional counter-force campaign against deployed
U.S. units, it could be sufficient to support a counter-value campaign similar to
the “War of the Cities” in the Iran-Iraq war.83 Iran could launch strikes against regional
population centers and key infrastructure to coerce Persian Gulf states to
deny the U.S. military basing access and overflight rights. Moreover, Iran could
threaten targets in Israel or Southern Europe with longer-range missiles armed
with WMD in an attempt to deter a U.S. military intervention in the Persian Gulf.
Attack Persian Gulf Energy and Water Infrastructure
As part of a campaign to coerce Persian Gulf states to deny basing and overflight
access to U.S. forces, Iran could launch missile attacks against Persian Gulf
energy infrastructure and water desalination facilities. Iran could also use its
proxies to launch G-RAMM strikes on critical government facilities and civilian
infrastructure across the Middle East.
Deny Passage through the Strait of Hormuz
Concurrent with its initial attacks against U.S. forces and regional governments,
Iran could use sea mines, ASCMs, and fast attack craft in an attempt
to control maritime traffic through the Strait of Hormuz. Mine warfare may be
one of Iran’s primary means of denying passage through the Strait.84 Though it
may hope to sink or severely damage a U.S. Navy vessel, the primary goal of an
Iranian mining campaign would be to deny safe access to the Persian Gulf and
force the U.S. to engage in prolonged mine countermeasure (MCM) operations
under threat from shore-based ASCMs. U.S. MCM ships, which lack the armor
and self-defenses of larger warships, would be unable to operate in the Strait
until these threats are suppressed.
To further complicate U.S. operations, Iran could deploy multiple ground-based
ASCM batteries in camouflaged and hardened firing positions along its coastline
and on Iranian-occupied islands in the Gulf. Using targeting data from
coastal radars, UAVs, surface vessels, and submarines, Iranian batteries could
launch salvo and multiple-axis attacks to saturate U.S. defenses. Similar to its
ballistic missile tactics, Iran may choose to withhold its more advanced ASCMs
until it is confident that the U.S. military has depleted its most capable kinetic
defenses.
Disrupt U.S. Military Networks
Using its own cyber capabilities or third-party “hackers for hire,” Iran could attempt
to interfere with U.S. military and civilian computer networks, including the
logistics networks that support U.S. force deployment and sustainment operations.
Potential Roles for U.S. DE Capabilities
This putative scenario would pose a significant challenge for a future U.S.
power-projection force. To open the Strait of Hormuz, U.S. forces would likely
need to suppress Iran’s air defense systems, defeat its fast attack craft and submarines,
counter land-based UAVs and ASCMs, and clear mines while operating
from land and sea bases that may lie well outside the range of Iran’s missile
threats. Moreover, U.S. forces that operate inside the effective range of Iran’s
A2/AD systems would need to rely on finite inventories of kinetic defenses to
counter threats that typically cost a fraction of the price of an SM-3, PAC-3, or
THAAD interceptor.
The DE concepts summarized below could assist U.S. forces to restore their
freedom of action in future operations against A2/AD complexes. They could also
act as significant force multipliers, expand options available to U.S. commanders,
and enable the U.S. military to break out of the current cost-imposing paradigm.
Countering an Iranian Balistic Missile Campaign
A future “DE family of systems” could enable U.S. ballistic missile defense operations
across the targeting chain and help restore the U.S. military’s ability to operate
from forward bases. Offensive ground- and sea-based laser systems could
dazzle or blind the sensors used by Iran for targeting and battle damage assessments
(BDA).85 HPM systems such as CHAMP or an enhanced version of CHAMP
carried by penetrating manned or unmanned aircraft could suppress the battle
networks that Iran needs to target its guided missiles effectively.86 The Air Force’s
ELLA program could lead to airborne SSLs powerful enough to reach across significant
distances with great precision to interdict missiles in their boost phase
of flight before they can reach Persian Gulf states, Israel, or Southern Europe.87 A
future high-power SSL carried on stealthy penetrating platforms could provide
the U.S. military with the capability to fly combat air patrols over enemy missile
launch areas with a persistence limited only by system endurance and the availability
of air refueling.
Directed-energy systems, combined with kinetic weapons, could also create
a robust network to defend U.S. forces and bases against air and missile threats.
DoD could deploy transportable ground-based chemical or solid-state lasers to
defend high-value fixed sites such as air bases, ports, and population centers
concentrated along the western coastline of the Persian Gulf.88 This could help
shift the cost-benefit ratio in favor of the United States and its partners by forcing
an enemy to expend large numbers of its ballistic missiles against defenses that
have deep magazines and a negligible cost per shot.89
Countering Threats to Surface Vessels:
Lasers as “Magazine Multipliers”
In the scenario postulated above, small-boat swarming attacks and multi-axis
ASCM salvos could overwhelm U.S. shipboard kinetic defenses such as guided
missiles and deck guns. These threats could prove particularly challenging for
U.S. MCM ships that typically lack sufficient on-board defenses to counter saturation
attacks. Furthermore, the loss of even a small number of low-density/
high-demand MCM assets would significantly extend the time needed to clear the
Strait of Hormuz, or even halt mine-clearing operations until these ships could
operate at reduced risk.90 By delaying U.S. counter-mining operations, Iran could
use time to its advantage, creating the breathing room needed to pursue a regional
coercive campaign.91
Maritime defenses that integrate kinetic and DE systems could change this dynamic.
A 100-200-kilowatt SSL mounted on the deck of an Arleigh Burke-class
guided missile destroyer (see Figure 10) or similar vessel could engage large
numbers of targets in quick succession and counter UAVs used to gather targeting
information, thereby permitting MCM ships to operate in the Sea of Oman
and Strait of Hormuz earlier in a campaign.92 Defeating ASCMs with SSLs at
these power levels would require the use of multi-ship, area-defense tactics
and/or relay mirrors to achieve lethal side shots against the cruise missile bodies.
Relay mirrors could also permit a single laser to engage missiles attacking
from different directions.
Linking airborne and surface DE capabilities with the Navy’s Cooperative
Engagement Capability (CEC) would create a layered and mutually supportive
kinetic and non-kinetic defense against swarming and salvo threats.93 Within the
CEC network, DE systems could serve as both precision sensors and weapons,
signifi cantly reducing the Navy’s use of expensive Harpoon, Hellfi re, Penguin,
Standard, and Evolved Sea Sparrow missiles. According to the Congressional
Research Service:
Compared to existing ship self-defense systems, such as missiles and guns, lasers
could provide Navy surface ships with a more cost effective means of countering
certain surface, air, and ballistic missile targets. Ships equipped with a combination
of lasers and existing self-defense systems might be able to defend themselves more
effectively against a range of such targets. Equipping Navy surface ships with lasers
could lead to ... a technological shift for the Navy—a “game changer”—comparable
to the advent of shipboard missiles in the 1950s.
Using high-energy SSLs for maritime defense would have a significant
force-multiplying effect. In a Persian Gulf scenario in which an enemy attempts
to use swarming tactics to overwhelm U.S. surface ships, it may be impractical to
simply shift additional ships to supporting fleet defense at the expense of strike
and anti-submarine missions. Moreover, the on-board kinetic defenses of surface
combatants, such as DDGs, could be exhausted in a short period of time
in high-threat environments, requiring them to leave their combat stations
to resupply at a rear-area port facility. In comparison, equipping DDGs with
high-energy laser defenses could free their capacity to carry other weapons
and significantly extend their time on station (see Table 1).
A future system based on fiber laser technologies developed by the LaWS program,
or slab lasers developed by the JHPSSL or DARPA’S HELLADS programs
could cost less than $20 million per unit.95 The cost of acquiring and integrating
a ship-based SSL weapon could be partially offset by reducing procurement of
expendable kinetic munitions.
Over the next twenty years, it may also be possible to develop long-endurance
manned or unmanned platforms, such as the Navy’s future Unmanned Carrier
Launched Airborne Surveillance and Strike (UCLASS) aircraft, that are equipped
with look-down, shoot-down SSLs to defend the fleet.97 Compared to ship-based
lasers, airborne lasers would suffer far less beam attenuation than ship-based
SSLs operating in maritime atmospheres, and may not need tactical relay mirrors
to achieve side shots against cruise missiles.
It is important to emphasize that DE defenses would complement, rather than
completely replace, kinetic close-in maritime defense systems. For example,
small fast attack craft can be difficult to disable or destroy with directed-energy
weapons alone, especially if the boats employ smoke or obscurants that can degrade
the effectiveness of laser beams.98 Furthermore, although solid-state DE
weapons may have nearly infinite magazines, they are still limited by system
cooling requirements and the need to dwell on targets long enough to create desired
effects. Thus, it is possible that very large swarms of fast attack craft firing
rockets at close range could saturate maritime DE defenses operating without the
support of kinetic countermeasures.99
Countering G-RAMM
Although mortar and rocket attacks have been a daily fact of life during operations
in Iraq and Afghanistan over the past decade, for the most part they have
been imprecise. A new generation of guided mortars and rockets could give irregular
forces the ability to hit targets repeatedly and with far greater precision. In a
future Persian Gulf conflict, state-sponsored proxy forces trained and equipped
to use such weapons could wreak havoc against vulnerable targets such as unsheltered
aircraft, marshaling yards, fuel depots, and vessels operating in littoral
areas. If equipped with advanced MANPADS, irregular forces could threaten air
operations in the Gulf, particularly airlifters and helicopters flying “low and slow”
while arriving at or departing from forward airfields. Although many of these aircraft
presently carry LAIRCM and similar very-low-power DE countermeasures,
these systems may not be effective against more advanced MANPADS that employ
imaging infrared seekers and/or multi-mode seekers.100
G-RAMM-equipped proxies would present a difficult operational challenge to
future U.S. operations in the Persian Gulf, particularly for military units tasked
with defending critical areas such as the ports and cities of regional partners.
Unlike ballistic or cruise missiles, the small footprint of G-RAMM weapons allows
irregular forces to use them in densely populated environments. Current kinetic
defenses such as the Counter-Rocket, Artillery and Mortar (C-RAM) system—
which is essentially a CIWS ashore—are magazine-limited and not well-suited for
use in heavily populated urban areas despite their use of self-destructing rounds to
reduce collateral damage.101
Directed-energy weapons used in combination with kinetic defenses could
shift the initiative away from irregular forces that employ G-RAMM. To protect
larger fixed bases, megawatt-class COIL ground-based defenses could interdict
hardened G-RAMM at a cost per shot that would be far less than even
the cheapest G-RAMM round. Future mobile SSLs could be small enough to
forward-deploy to remote sites or used in rugged terrain to protect maneuver
forces.102 Long-endurance UAVs outfitted with relay mirrors and electro-optical/
infrared sensors could support “G-RAMM hunter-killer” combat air patrols
operating over U.S. ground forces in coordination with fixed-site COILs or
ground-mobile SSLs. These UAVs could enable high-energy laser strikes on
G-RAMM sensors, guidance systems, and their operators before attacks are
launched, or detonate rounds inflight with a lower risk of causing unwanted
collateral damage compared to the use of kinetic defensives.103
enab ling airsea batt le in
the western pacific
An Illustrative Scenario
The following scenario illustrates how China might execute an A2/AD strategy
fifteen to twenty years in the future. The scenario assumes that China begins
hostilities, the United States and its allies lack adequate intelligence and warning
about a pending attack, and U.S. forces and Western Pacific posture are based on
the current defense program projected into the future.104
Launching a First Strike again st U.S
Space and Cyber Infrastructure
At the beginning of hostilities, China could use its DE capabilities and offensive
electronic-warfare systems in a coordinated effort to blind U.S. and allied
sensor networks. This effort could be complemented by computer network attacks
against U.S. and allied networks—both military and civilian—for the purpose
of delaying and disrupting a coordinated military response.
Degrade Operations from U.S. Forward Bases
As China launches a first strike in space and cyberspace, it could simultaneously
salvo ballistic missiles and land-attack cruise missiles against U.S. bases located
across the Western Pacific. China could use its large inventory of long-range,
precision-guided munitions to target specific facilities at these bases, including
vulnerable petroleum, oil, and lubricant (POL) storage areas, to reduce the U.S.
military’s tempo of operations and prevent the deployment of additional forces to
the region.105 As explained in AirSea Battle, the PLA could begin an anti-access
offensive against the United States by using salvos of missiles carrying submunitions
capable of creating a range of effects, such as disabling air defense radars,
damaging runways, and destroying unsheltered aircraft on the ground.106 With
U.S. air defenses weakened, follow-on waves of air and missile strikes could significantly
degrade U.S. offensive and defensive operations staged from bases in
Japan, Guam, and other forward locations.107
Attack U.S. Surface Vessels
Although the PLA may be unable to completely deny the vast expanse of the
Western Pacific to U.S. surface forces, it could seek to significantly increase
the risk to U.S. naval operations within this “keep-out” zone. Using land-based
ASBMs, air- and submarine-launched ASCMs, and wake-homing torpedoes,
the PLA could attack U.S. and allied surface vessels—particularly U.S. CSGs—at
ranges out to 1,500 nm from mainland China.108 The U.S. military’s ability to
project conventional power would be severely constrained should China succeed
in preventing Navy CSGs from deploying to within the effective ranges of their
aircraft and land-attack missiles. Moreover, PLA anti-surface capabilities could
force a large part of the U.S. fleet to engage in defensive maneuvers as opposed to
offensive operations.
Interdict Sea Lines of Communication
PLA attack submarines and long-range aircraft could interdict sea lines of communication
(SLOCs) throughout the Western Pacific that are critical to sustaining
U.S. power-projection operations. PLA Navy nuclear attack submarines (SSNs)
patrolling sea lanes near Hawaii and in the Indian Ocean could interdict the flow
of supplies and reinforcements and compel the U.S. Navy to divert resources to
convoy escort and anti-submarine warfare missions.
Potential Roles for U.S. Directed-Energy Capabilities
Although base hardening and improving kinetic missile defenses may help reduce
the impact of repeated ballistic missile salvos on U.S. operations in this
scenario, such measures would be extremely expensive. Moreover, China could
seek to counter these moves by expanding its guided munitions inventories and
striking targets that are difficult to harden, such as port facilities. Alternatively,
the U.S. military could develop new DE systems that would help reverse this unfavorable
cost-imposing dynamic.
Enabling a Blinding Campaign
The PLA’s ability to strike U.S. and allied targets across long ranges using ballistic
missiles, ASBMs, ASCMs, and UAVs would depend heavily on its ability to
“see” over great distances using over-the-horizon radars (OTHRs), space-based
sensors, and airborne networks. Conducting blinding operations to destroy or
disable these long-haul sensors early in a conflict could be the most critical line of
operation in an AirSea Battle campaign.109 Future DE weapons could contribute
significantly to blinding operations in at least two ways.
>> First, the U.S. military could use HPM weapons to disrupt or disable enemy
land-based OTHRs and airborne sensors. It may be difficult to knock OTHR
arrays out of action for prolonged periods using conventional attacks only.
HPM weapons could degrade or destroy unshielded OTHR components, as
well as temporarily or permanently negate the critical systems airborne surveillance
platforms need to perform their missions.110
>> Second, although the United States has demonstrated kinetic ASAT capabilities,
there are distinct advantages to using directed energy to create a range of effects
against opposing space-based sensors.111 At lower power levels, DE ASATs could
“dazzle” or temporarily blind space-based sensors and third-nation satellites
that are providing imagery to enemy forces. At higher power levels, land-based
DE weapons could permanently blind optical sensors, leaving an enemy and its
supporters to choose between shuttering their satellite sensors to preserve them
for future use, or risk losing them permanently. Laser defenses on Navy surface
ships could be used in this role as well, and could be particularly effective
against the overhead satellites used to target CSGs.112
Conducting a Balanced Counter-Missile Campaign
DE systems could support U.S. counter-missile operations across the entire kill
chain during an AirSea Battle campaign.113 Low-power laser systems could provide
secure, low-probability of intercept, and nearly jam-proof airborne data
links for passing missile targeting and BDA data to higher echelons of command.
As mentioned previously, low- and high-power lasers and HPM devices could degrade
or blind enemy long-range ISR sensors and networks, complicating their
ability to find and target mobile carrier strike groups. Although PLA strikes
against fixed targets are likely to continue despite the best efforts of a layered
missile defense network, the PLA’s ability to conduct accurate BDA would be extremely
difficult without long-range surveillance. Uncertainty over the effectiveness
of its strikes could cause the PLA to waste missiles against targets that have
little or no value.
Future DE capabilities could also interdict ballistic missiles in their boost
phase. Today, developmental COILs are the nearest thing the United States has to
a potential DE capability that could reach across hundreds of kilometers to destroy
or disable ballistic missiles shortly after launch. Unfortunately, the COIL-based
ABL lacked the survivability required to operate close enough to mainland China
to engage land-based missiles in their boost phase.114 A future high-power SSL
mounted on low-observable, long-range platforms could conduct combat air patrols
within range of missile launch areas. These DE devices may also be capable
of disabling missile transporter erector launchers (TELs) on the ground.
By 2030, it is highly likely that advances in power generation, efficiency, and
beam quality technologies could lead to SSLs that could be integrated into smaller
aircraft, such as a stealthy fighters and UCLASS. DE-equipped UCLASS squadrons
could sustain missile-defense combat air patrols with a persistence limited
only by the aircraft’s system reliability and the availability of air refueling.
These UCLASS patrols could also engage both surface-to-air missiles (SAMs)
and air-to-air missiles, providing an additional defensive layer for friendly surveillance
and strike aircraft.
In terms of effectiveness, coverage, and cost per engagement, DE weapons capable
of interdicting ballistic missiles would represent a major step forward for
DoD. Combined with kinetic interceptors, DE systems could provide U.S. forward
operating locations with a formidable and cost-effective missile defense network.
Countering IADS
In addition to fielding large quantities of ballistic and cruise missiles, the PLA
possesses a sophisticated IADS consisting of advanced long-range SAMs, hardened
and deeply buried command and control networks, and long-range aircraft.
Advanced SAMs such as derivatives of Russia’s long-range S-300/400/500 systems
could threaten U.S. aircraft and cruise missiles at significant distances
from China’s coastline. By 2030, the PLA will likely field a fleet of fourth- and
even fifth-generation fighters. Stealthy interceptors, such as the recently unveiled
J-20, could contest U.S. air and maritime dominance over critical areas such as
the Taiwan Strait.
By 2030, new DE capabilities could help shift the balance in favor of U.S. offensive
counter-air operations. Cruise missiles and stealthy unmanned aircraft
equipped with HPM payloads could degrade the PLA’s command and control
networks, radars, and SAM systems, thereby helping penetrating ISR and strike
platforms to complete their missions. Bombers could launch large numbers of
low-observable HPM cruise missiles to suppress enemy air defenses from secure
standoff distances, creating opportunities for other aircraft to conduct penetrating
missions. A smaller stealthy UAS with HPM payloads could enhance the
utility and persistence of such attacks. These strikes could be conducted with
little prior warning and might impose significant costs on an enemy, especially if
each UAS HPM weapon system could strike scores of targets per sortie.
Strike packages and combat air patrols typically require support aircraft, such
as air refueling tankers and airborne warning and control systems (AWACS), which
are highly vulnerable to SAMs and air-to-air missiles. Solid-state, high-energy lasers
onboard these larger aircraft would give them a self-defense capability that
could allow them to fly orbits closer to mainland China and thus improve their
ability to support penetrating platforms.115 U.S. s urface ships outfitted w ith l asers
of sufficient power, such as an advanced solid-state system supported by
tactical relay mirrors, could also provide supporting “bubbles” of security for
forward-area air refueling and wide-area surveillance operations.
summary
In a future Persian Gulf scenario, DE systems capable of countering ballistic missiles,
fast attack craft, UAVs, ASCMs, and G-RAMM salvos could help prevent an
enemy from conducting a cost-imposing, coercive campaign against the United
States and its regional partners. Similarly, DE capabilities could shift the operational
initiative in favor of the U.S. military during an AirSea Battle operation in
the Western Pacific.
While the U.S. military could partially mitigate the effects of enemy attacks in
either region, symmetric responses would not fundamentally alter the emerging
unfavorable cost-exchange ratio between enemy offensive systems and U.S. defensive
capabilities. For example, each expansion of an enemy’s ballistic missile
arsenal might require far more expensive U.S. investments in base hardening
and kinetic interceptor programs. In the long run, a defensive posture based solely
on dispersal, hardening, and kinetic defenses might therefore be operationally
ineffective and fiscally infeasible.
Instead of falling into a cost-imposition trap, DoD has the opportunity to
develop DE capabilities that will create new operational advantages for future
power-projection forces. Moreover, considering the low cost per shot of DE
weapons, a DE family of systems could shift the cost-imposition dynamic in
favor of the United States.
.
In 2007, the Defense Science Board Task Force on Directed Energy Weapons concluded
that:
Directed energy offers tremendous promise in improving operational capabilities
to conduct certain missions. The potential of these systems is such that the
Department should increase the attention paid to the scope and direction of the
efforts underway today. Even after many years of development, there is not a single
directed energy system fielded today, and fewer programs of record exist than in
2001. This circumstance is unlikely to change without a renewed focus on this important
area.116
These insights are as true today as they were in 2007. The latest defense budget
does not include a single program of record for the full-scale development of a
high-power DE weapon and, given continuing pressures on its budget, it will be
difficult for DoD to initiate a major DE program in the near future. Understanding
why this is so requires an appreciation of the technological, cultural/organizational,
and resource challenges that continue to affect the transition of promising
new DE technologies to real-world capabilities.
techno logica l cha llenges
Over the past twenty years, DoD terminated three high-profile DE programs that
over-promised in concept and under-delivered in practice.117 Practical military
applications for chemical HELs, in particular, were limited by their large size,
weight, and supporting logistics requirements. This may no longer be the case.
Modern COILs have several times the output of previous devices and could be
packaged into deployable systems to defend fixed sites. Similarly, while there is a
need to further ruggedize and reduce the size, power, and cooling requirements
of high-power SSLs, HEL technologies are sufficiently mature to support the development
of new weapon systems in the near to mid term.
Improving SSL Technologies
While SSLs are inherently smaller and lighter than chemical lasers, further increasing
their electrical efficiency and reducing the size of the systems needed
to cool their lasing media could accelerate their transition to operational capabilities.
Power is lost as waste heat between each component of an SSL: between
the power source and the pump, between the pump and the lasing medium, and
between the lasing medium and the laser output. When any of these components
become too hot, their performance degrades—reducing the overall system efficiency—
and they can even be damaged.
Recent advances in SSL technologies have demonstrated significant progress
toward improving the efficiency and reducing the cooling requirements
of high-power SSL systems. SSLs developed by the High Energy Laser Joint
Technology Office’s JHPSSL program have achieved up to 19 percent wall-plug
efficiency at 100 kilowatts of output.118 DoD research to increase SSL wall-plug
efficiency to 30 percent or greater includes efforts to improve the efficiency of
the laser diodes that pump the lasing media. In the past, SSLs were “pumped”
by flash lamps that emitted a variety of wavelengths and produced considerable
amounts of heat that required large cooling systems to dissipate. Today, SSL lasing
media are pumped by photons generated by electrically powered laser diodes.
As part of this effort, DARPA’s Super High Efficient Diode Sources (SHEDS) program
has increased the electrical-to-optical efficiency of laser diodes from 50
percent to more than 70 percent. The ultimate goal of this program is to achieve
over 80 percent efficiency.119
Since size, weight, and cooling requirements are prime determinants of the
potential mobility of a high-energy laser weapon, these and other DoD technology
initiatives such as DARPA’s HELLADS program could, if successful, lead to
fully contained DE devices that could be mounted easily on current and future
platforms. For example, it is now more a matter of engineering than invention to
install current-technology SSLs on Flight III Arleigh Burke-class DDGs to defend
against UAVs, small boats, and possibly cruise missiles. It may also be feasible to
develop modular SSL packages that would give the U.S. Navy’s Littoral Combat
Ships (LCS) a more robust self-defense capability against air and missile threats.
Over time, more efficient (and thus more compact) SSLs might be installed on the
Air Force’s new long-range bomber and smaller systems such as fighters and the
U.S. Navy’s UCLASS.
Need for Additional DE Lethality Testing
One additional technological challenge deserves mention. In 2007, the Defense
Science Board concluded:
The Department needs an authoritative single source database for directed energy
efforts similar to the munitions effects manual for kinetic weapons. Development
of meaningful concepts of operations and analyses of military utility require the
foundation of credible weapons effects data and assessments.120
While DoD possesses a large body of reliable data for non-lethal DE systems like
the ADS and laser dazzlers, it still lacks sufficient, reliable data on the effects
of high-energy lasers and HPM weapons against a range of threats. During the
research phase of this assessment, DE technology experts from every Service,
the Office of the Secretary of Defense, and industry emphasized the need for additional
DE lethality testing to determine the thresholds required to achieve effects
on challenging targets, including G-RAMM, cruise missiles, and ballistic
missiles. Such a database could help inform future DE systems requirements and
investment decisions.
cultura l and organi zationa l cha llenges
Much has been written regarding the U.S. military’s reluctance to adopt new
technologies that are unproven on the battlefield. In a 2009 report, CSBA suggested
that historically, the Services were most likely to embrace new capabilities
when they “solved an important problem at the operational level of war, sustained
a way of fighting already integral to that Service, or preserved the Service’s
dominant sub-cultures.”121
In the case of DE, perhaps a fourth reason could be added to this list: The
Services may be waiting for near-perfect technological solutions to emerge before
committing the resources needed to field high-power DE capabilities. For
example, the Navy may choose to forego developing an SSL that could be integrated
into the fleet in the near term in favor of a FEL that could require another
twenty years or more of development—and possibly a new hull design—before it
becomes operational. With sufficient funding, however, a ship-based high-energy
SSL could reach initial operational capability before 2018. Instead of pursuing
this option, previous defense budgets favored technologies related to a FEL
weapon.122 While a FEL with an output of a megawatt or greater would provide a
significant capability for interdicting ASCMs and potentially ASBMs, absent significant
technological breakthroughs, the very large size, thermal management
challenges, and shielding required to protect humans and electronics from the
stray radiation produced by FELs make them long-shot candidates for practical
ship-borne weapon systems for the foreseeable future.123
As a second example, the Army desires a highly mobile, ruggedized SSL that
could provide ground maneuver units with the means to defend against G-RAMM
attacks. Similarly, the Air Force has invested the majority of its DE budget in
technologies that could lead to weapon systems for airborne platforms. While
an SSL weapon that is sufficiently compact and ruggedized to be truly mobile
may be available in five to ten years, the Army and Air Force could immediately
take advantage of mature technologies to develop a ground-based, relocatable
chemical laser weapon to defend fixed sites. While this weapon would not be fully
mobile, it could be deployed by air or sea to provide bases in the Western Pacific
and Southwest Asia with significantly enhanced defenses against air and missile
threats. The Army, however, has shown little interest in high-energy lasers that
are not fully mobile, and the Air Force does not seem disposed toward funding
DE technologies that have no potential to be carried by aircraft or cruise missiles.
To overcome institutional desires to hold out for “perfect” systems, it may be
useful to acknowledge that DE weapons will not be silver-bullet solutions that
will completely replace program of record kinetic weapons. In fact, almost all of
the DE weapons concepts discussed in Chapter 3 would be most effective when
combined with kinetic systems to provide greater levels of protection against
advanced threats. As with all military weapon systems, DE weapons will have
operational limitations, such as a degraded ability to interdict targets through
moist air, fog, and clouds.124 For these reasons, combining DE and kinetic weapons
could permit future warfighters to compensate for the operational shortcomings
of each system while increasing overall mission effectiveness.125
One additional trait of DoD DE technology programs is worth considering:
they are all led by S&T organizations, such as the Navy’s Office of Naval Research,
the Army’s Space and Missile Development Command, the Air Force Research
Laboratory, and the High Energy Laser Joint Technology Office. These organizations
are dependent on science and technology funding lines. Moreover, they are
populated with highly trained specialists who are typically rewarded for advancing
the science of DE, as opposed to fielding operational weapon systems.
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