High energy laser weapons

AARMS
TECHNOLOGY
Vol. 9, No. 2 (2010) 327–341
High energy laser weapons
TIBOR ÁGOSTON
Miklós Zrínyi National Defence University, Budapest, Hungary
I introduce the latest invention of laser researches, but prior to the most advanced
technologies, I describe the Strategic Defense Initiative, that paved the way for today’s
weapons. These technologies have numerous hidden advantages and possibilities,
unfortunately they are pretty expensive though. The place of installation varies from
air-based (airborne) to ground-based units. Researchers face lots of difficulties that
they have to get over if they wanted to manufacture cheaper, greater number of laser
defence systems in order to protect human lives.
Introduction
Humans fight in wars since the beginning of history. The outcome has always been
influenced by the advancement of military technology and by the application of
amazing and newly invented technologies.
New inventions, procedures revolutionized warfare. The appearance of gunpowder,
rifles, tanks, aircraft, rockets and later the atomic bomb in the arzenal of military
technolgies are good examples.
Waring parties were always concerned about a “death beam”, that is capable of
destroying everything, that has no defense against, that can burn up all the hostile
weapons and ships. In the course of the researches, scientists seek a silver bullet, that
can shift the balance between waring parties.
The scientific technological revolution in the 20th century had a deep impact on
weapon researches. For the very first time, Albert Einstein was the one who came up
with the idea of a laser weapon in 1917. It took a long time, till Theodore Maiman
demonstrated the first operational laser source in Hughes Research Laboratories on May
26, 1960.
The special features of laser made it come into prominence of military officials and
it seemed, that the legendary “death beam” was found.
This thesis is dealing with this procedure. It sums the main parts and details of the
Strategic Defense Initiative, with the emphasis being put on the creation of laser
weapons. After shutting down the program, its results were used in the Airborne Laser
program and contributed to the creation of National Missile Defense Program. It is in
Received: September 3, 2010
Address for correspondence:
TIBOR ÁGOSTON
E-mail: [email protected]
T. ÁGOSTON: High energy laser weapons
operational stage and successfully tested by today. Of course researchers face lots of
difficulties and obstacles, but the potential possibilities overhang the expensis.
In the third chapter, I deal with the possibilities of the application of ground-based
laser beams throught the SKYGUARD project, that could revolutionize the 21 st
century’s warfare, as long as troops can be defended from hostile artillery barrage.
I would like to deal with these exciting future weapons in a small compass.
1. Strategic Defense Initiative
The Strategic Defense Initiative (SDI), also known as Star Wars, was established by
President Ronald Reagan on March 23, 1983. The main purpose of this initiative was to
develop and install ground and space-based defence systems in order to protect the
United States from nuclear ballistic-missiles. The idea behind the project was to create a
three-tiered defensive system with the ability to intercept a target missile in the boost,
midcourse and terminal phases of its flight, minimizing its effects. The Strategic
Defense Initiative Organization was founded in 1984 in order to supervise the SDI.1
Figure 1. SDI
Many scholars in those ages stated that this project was not only impossible to create
with the contemporary technologies, but at least ten more years of research was needed to
learn if it is ever possible. With political pressure, both domestic and international,
combined with budgetary conflicts, the Strategic Defense Initiative was sentenced to
failure from the beginning. It was never fully developed or deployed, but some inventions
and researches have paved the way for today’s anti-ballistic missile systems. By the end of
the Strategic Defense Initiative, thirty billion dollars had been invested in the program and
no laser and mirror system was ever used neither on land, nor in space.1
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The concept would have been the following:
Figure 2. Principal of SDI
Let us see how the different weapons and programs are aligned:
1.1. Ground-Based Weapons
Extended Range Interceptor (ERINT)
The ERINT program was part of the SDI’s Theatre Missile Defense Program. It was
an extension of the Flexible Lightweight Agile Guided Experiment (FLAGE), which
included developing hit-to-kill technology and demonstrating the guidance accuracy of
a small, agile, radar-homing vehicle. ERINT differed from FLAGE in its actuation as it
was equipped with a new solid-propellant rocket motor that allowed it to fly faster and
higher than FLAGE.2
o Homing Overlay Experiment (HOE)
The HOE was the first successful “hit-and-kill” system that consisted of infrared
homing sensors that would permit an interceptor to guide itself into the path of an
incoming warhead and collide with it. The Army’s HOE used a Kinetic Kill Vehicle
(KKV) to destroy a ballistic missile. The KKV was equipped with an infrared seeker,
o
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guidance electronics and a propulsion system. Once in space, the KKV could extend a
folded structure that consisted of 36 aluminium ribs with stainless steel fragments,
similar to an umbrella skeleton of 4 m diameter to enhance its effective cross section.
This device would destroy the ICBM reentry vehicle on collision.3
o Exoatmospheric Re-entry-vehicle Interceptor System
In 1985 the Exoatmospheric Re-entry-vehicle Interceptor Subsystem (ERIS) project
office began with the mission to develop a KKV that would intercept enemy missiles
outside of Earth’s atmosphere. The first test took place in 1991, while the second one
occurred in 1992. Following the end of the Cold War, the SDI program was reoriented
towards what was called GPALS (Global Protection Against Limited Strikes), and ERIS
itself was not directly developed into an operational system. Budget cuts also
contributed to the end of this program.4
1.2. Space-Based Programs
The Space-Based Interceptor (SBI)
This system was designed to consist of groups of interceptors housed in orbiting. Final
hover testing took place in 1992 using miniaturized components similar to what would
have actually been used in an operational interceptor. The program was frozen in 1993,
and it was terminated in 1994 as interest shifted from defence against strategic missiles
towards defence against theatre ballistic missiles launched by third-world countries. The
remaining prototypes were eventually evolved into the Brilliant Pebbles program.5
o Brilliant Pebbles
This program consisted of numerous highly autonomous interceptors floating
independently in orbit. As soon as the attack is detected, these tiny rockets would have
been activated and launched to intercept the hostile missiles. At the verge of collision,
these rockets would encounter a hail of fire as they hit the hostile missile. It is like an
orbital shotgun. The USSR would have dealt with thousands of small, hard-to-find
interceptors instead of several hundred large, easy-to-find rockets.6
o
1.3. Sensor Programs
Boost Surveillance and Tracking System (BSTS)
The BSTS was intended to provide early, accurate, and reliable tactical warning and
attack assessment of ballistic missile launches, while also providing monitoring of
peacetime launches. The BSTS concept used a wide field-of-view infrared mosaic
sensor to cover the entire earth, below and above the horizon, while the large number of
detectors would have provided high sensitivity and temporal resolution. Unfortunately it
proved to be expensive.7
o
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Space Surveillance and Tracking System
SSTS was a system originally designed for tracking ballistic missiles during their
mid-course phase. It was designed to work in conjunction with BSTS, but was later
scaled down in favour of the Brilliant Eyes program.8
o Brilliant Eyes
It was a simpler progeny of the SSTS that focused on theater ballistic missiles rather
than ICBMs and was planned to operate in conjunction with the Brilliant Pebbles
system. In the late 1990s it became the low Earth orbit component of the Space Based
Infrared System (SBIRS).9
o
1.4. Directed-Energy Weapons Programs
X-ray laser
It was designed to create a curtain of X-ray lasers powered by nuclear explosions.
The curtain was to be deployed by series of missiles launched from submarines or
satellites. The satellites would be powered by energy from the warhead detonation and
this power would be used to pump a series of laser emitters, allowing each satellite to
shoot down many incoming warheads simultaneously. It was thought to be faster than
an optical laser, which could only shoot down warheads one at a time.10
o Chemical laser
In 1985, the Air Force tested an SDIO-funded deuterium fluoride laser known as
Mid-Infrared Advanced Chemical Laser (MIRACL). First the laser was tested in
laboratory with success. Later it was tested on target drones simulating cruise missiles
for the US Navy, with some success. Following SDIO’s closure, the MIRACL was
tested as an Anti-satellite weapon, with mixed results. The technology was also used to
develop the Tactical High Energy Laser which is being tested to shoot down artillery
shells. Currently this laser is used by Missile Defense Agency’s Airborne Laser
program.11
o Neutral Particle Beam
In 1989, the Beam Experiments Aboard a Rocket (BEAR) program launched a
rocket containing a neutral particle beam (NPB) accelerator. The test successfully
demonstrated that a particle beam would operate and propagate as predicted outside the
atmosphere and that there are no unexpected side-effects when firing the beam in space.
After the rocket was recovered, the particle beam was still operational.12
o Laser and Mirror
In February 1990, the Relay Mirror Experiment demonstrated critical technologies
for space-based relay mirrors that would be used as an SDI directed-energy weapon
system. The experiment validated stabilization, tracking, and pointing concepts and
o
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proved that a laser could be relayed from the ground to a 60 cm mirror on an orbiting
satellite and back to another ground station with a high degree of accuracy and for
extended durations.
o Hypervelocity Rail Gun
A hypervelocity rail gun works very much like a particle accelerator as it converts
electrical potential energy into kinetic energy imparted to the projectile. The projectile
is attracted down the rails by electric current flowing through a rail. Through
the magnetic forces that this system achieves, a force is exerted on the projectile
moving it down the rail. Rail guns can generate muzzle-velocities of 2500 meter per
second. At this velocity, even a rifle-bullet sized projectile will penetrate the front
armour of a main battle tank, let alone a thinly protected missile guidance system.13
2. YAL-1 Airborne Laser – ABL
On February 11, 2010, a short-range ballistic missile was destroyed by a high energy
weapon, mounted on a heavily modified Boeing 747, while both were in flight. The
Missile Defense Agency’s Airborne Laser TestBed carries a megawatt-class high power
chemical oxygen iodine laser (COIL). It is coupled with precision pointing and
atmosphere correction system. It is proved to be capable of knocking a ballistic missile
out of the sky. It is supposed to engage multiple targets and can hit them from hundreds
of kilometres away. Of course, we are talking about the YAL-1 Airborne Laser that was
designed to intercept short-range ballistic missiles.
Figure 3. Boeing YAL-1 Airborne Laser
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2.1. Short history of ABL program
The Airborne Laser program was initiated by the Air Force in 1996. In 2001, the
program was transferred to the Missile Defense Agency and converted to an acquisition
program. There were two milestones: in late 2004, COIL achieved its first successful
functioning during the ground tests, the so called “first light” and secondly, the “first
flight”, when the aircraft flew with the battle management and fire control on board.
Later on, in 2005, battle management and beam control proved to be effective and
finally a beam was fired at lethal power. Significant researches did not take place in
2006. This year was spent on bringing the laser to perfection and applying some
modifications on the fuselage. In 2007, the program was successfully demonstrated in
active flight tests, while all other systems were also tested. In 2008, the team completed
installation of the high-energy laser in the aircraft and began firing the laser onboard the
aircraft in ground testing. In April 2009, ABL began conducting flight tests with the
entire weapon system integrated aboard the aircraft.15
The whole project is being accomplished by a group of corporations. Boeing provides
the aircraft, battle management, overall systems integration and testing. Northrop
Grumman supplies the megawatt-class, high-energy laser and one of the low-power
illuminator lasers. Lockheed Martin provides the beam control/fire control system.15
2.2. Structure and its functioning
The weapon itself uses three different laser systems in order achieve the desired goal: a
low-power multiple beam for gaining all required information on the target, a pointing
laser that provides data on the rapidly changing characteristics of the target and the
primary laser.
Using six infrared lasers, installed along the length of the aircraft’s fuselage, the
ABL constantly scans the horizon for missiles. Once a target is found, a laser-ranging
pod measures its distance with carbon dioxide ray of light. Three low power tracking
lasers calculate missile course, speed, aim point, and air turbulence. Air turbulence
deflects and contorts the laser beam. The ABL adaptive optics uses the turbulence
measurement to compensate for atmospheric errors.
A track laser then pinpoints a specific target area on the incoming missile. Once all
systems are go, a high energy laser is fired at the target. This main laser is located in a
turret on the aircraft nose. It contains a 1.5 m telescope mirror system inside the nose
that focuses the laser beam onto the missile. If it hits the target for at least 2–3 seconds,
the missile explodes. Where the missile carries liquid fuel, the laser can heat a spot on
the missile’s fuel tank, causing an increase in internal pressure resulting in catastrophic
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failure. Alternatively, the missile is heated in an arc around its circumference and
crumples under atmospheric drag force or its own g-force.16
Figure 4. Detection zones of ABL
Figure 5. Measuring laser
Figure 6. Tracking laser
Figure 7. Firing at target
All of this occurs in approximately 8 to 12 seconds.
The ABL was designed for use against tactical ballistic missiles. These have a
shorter range and fly more slowly than ICBMs. The MDA has suggested the ABL
might be used against ICBMs during their boost phase. This could require much longer
flights to get in position, and might not be possible without flying over hostile territory.
Liquid-fuelled ICBMs, which have thinner skins, and remain in boost phase longer than
TBMs, might be easier to destroy.
The COIL is composed of six interconnected modules, each as large as a sport-utility
vehicle turned on end. Each module weighs about 6 tones and has 3,600 separate parts.
When fired through a window in the aircraft’s nose turret, it produces enough energy in a
5-second burst to power a typical American household for more than one hour. COIL is a
megawatt-class laser, as opposed to the less-powerful kilowatt-class targeting laser. Its
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wavelength is 1,315 microns.16,17 According to an American Physical Society report in
2004, the Airborne Laser could shoot down a typical liquid-fuel intercontinental ballistic
missile (ICBM) from up to 600 km away. However, against solid-fuel ICBMs, which are
more resistant to heating, the useful range would be about 300 km. The ABL was
expected to achieve effective range of at most 400 km.18
Figure 8. Nose turret
2.3. Problems and disadvantages
The ABL uses chemical fuel similar to rocket propellant to generate the high laser
power. Current plans call for the capability to carry enough laser fuel for about 20 shots,
or perhaps as many as 40 low-power shots against fragile TBMs. The ABL aircraft must
land to refuel the laser. Preliminary operational plans call for the ABL to be escorted by
fighters and possibly electronic warfare aircraft. The ABL aircraft would likely orbit
near potential launch sites for long periods, flying a figure-eight pattern that allows the
aircraft to keep the laser aimed toward the missiles. The aircraft can be refuelled in
flight, enabling it to stay aloft for long periods.
Theoretically, ABL is capable of being used against hostile aircraft, cruise missiles
or low-earth-orbit satellites. Although ABL's infrared target acquisition system is
designed to detect the heat exhaust of TBMs in boost phase, satellites and other aircraft
could have a much lower heat signature, making them more difficult to detect.
Use against ground targets seems to be unlikely. Despite the difficulties of acquiring
and tracking a ground target, firing through the dense atmosphere would weaken the
beam. Ground targets such as armoured vehicles are not fragile enough to be damaged
by a megawatt-class laser. Another program, the Advanced Tactical Laser, envisions
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air-to-ground use of a megawatt-class laser mounted on an aircraft that flies on a lower
altitude, such as the C-130 Gunship.19
About the presence of the ABL, the program is on hold. On April 6, 2009 Defense
Secretary Robert Gates announced that: “We will cancel the second airborne laser
prototype aircraft. We’ll keep the existing aircraft and shift the program to an R&D
(Research and Develop) effort. The ABL program has significant affordability and
technology problems, and the program’s proposed operational role is highly
questionable.” At that time the ABL program was eight years behind schedule and $4
billion over cost.18 As we see, the program itself is quite expensive and it is still not
finished. It is highly understandable, why top officials decided to put the program on hold.
3. SKYGUARD – Tactical High Energy Laser Program
Northrop Grumman has developed a new laser-based air defence system for U.S. and its
allies that require near-term defence against short-range ballistic missiles, short- and
long-range rockets, artillery shells, mortars, unmanned aerial vehicles and cruise
missiles. The laser is called Skyguard and can release laser beams of such high intensity
that can make a missile explode in a few seconds.
Figure 9. SkyGuard
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Skyguard is derived from the successful Tactical High Energy Laser (THEL) test
bed and its predecessors developed by Northrop Grumman for the U.S. Army and the
Israel Ministry of Defence. Benefiting from significant technological advancements,
Skyguard has higher power than previous systems do and a larger beam, making it a
much more effective system.
The need of such weapon was born roughly ten years ago, when Hezbollah
guerrillas fired hundreds of Katyusha rockets into Israel. The attacks prompted
President Bill Clinton and the Israeli prime minister, Shimon Peres, to agree to develop
laser defence system, meant to destroy the rockets in flight.
Like earlier systems developed by Northrop Grumman, Skyguard is a multi-mission,
soldier-operated, compact and transportable laser weapon system designed for field
deployment and operations. It can focus the high intensity laser with high accuracy on
the most vulnerable part of the missile that is usually the warhead. The beam makes the
compartment so hot that the explosives inside are destroyed well before they reach their
target.
Skyguard has an infrared camera that continuously scans the horizon in a
9–12 km radius around the installation site. When it finds any heat emitting device in air
it scans it for its heat signature and checks it in a database of known heat signatures. If
the result reveals the presence of a missile, the laser is activated and it focuses on the
main vulnerable compartment of the missile structure that heats it up and destroys it in
mid air.20
“We believe that no other weapon of any kind, or any system being developed
today, can offer the kind of protection we’ve proven Skyguard can provide,” said Alexis
Livanos, president, Northrop Grumman Space Technology. “Skyguard offers the
earliest possible implementation of an operational laser weapon system for defence
against a wide range of threats.”21
Since 2000, Tactical High Energy Laser has shot down 28 operational Katyusha
rockets, including single and multiple salvos and other incoming artillery rockets.
Shooting down rockets, which are bigger in dimensions and relatively slow, is not a
new skill, it has been demonstrated before. What about faster and smaller incoming
threats, like mortar or artillery shells? The next challenge was to intercept artillery
shells. During the tests, every incoming projectile was shot down. Tests kept going on
in 2004, when large calibre rockets were intercepted by Skyguard. In the course of the
tests, the fact that Skyguard is capable of maintaining tracking the projectile through
intervening clouds was proven. In the next phase it faced live mortar rounds, one of the
most serious threats against deployed forces serving in Afghanistan or Iraq. It
successfully shot down single shells and shells fired in salvo during the tryout.
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Figure 10. Operation of SkyGuard
According to these tests, Skyguard would be the perfect defence in operational
zones against randomly fired mortar shells. Equipping ISAF camps in the Mid-East
would prevent friendly forces from suffering unnecessary losses. A single Skyguard
system can defend deployed forces, a large military installation, and/or a large civilian
population or industrial area. One Skyguard system is capable of generating a protective
shield of about ~20 kilometres in diameter.22
Anyhow the technology is pretty expensive as individual units cost roughly $150
Million but if the units are mass produced then the system will cost somewhere around
$30 Million.22
According to a military analyst from Tel Aviv University, firing the laser just once
would cost approximately $3,000. Covering the whole border of Israel would require
several dozens of the system, therefore the costs would run up to billions of dollars.23
There is another concern about Skyguard. Since it uses chemical laser, people worry
about its exhausted gases during operation. According to Northrop Grumman, the
system’s exhaust is not toxic, but mostly helium and steam. Therefore, the system
requires a “keep out zone” of 30 meters, smaller than conventional rocket systems such
as Stinger and Patriot.22
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Summation
As we see, these systems are highly expensive and are still in development and test
stage in our days. At the same time their potential capabilities and possibilities overhang
the currently sounded disadvantages and financial difficulties. If we could upgrade these
systems both operationally and financially, numerous human lives can be saved. All
decision-makers have to accept the fact, that a human life – a soldier’s in operational
theatre or an innocent civilian’s – cannot be measured in dollars.
We still face a long and demanding way till we can put these systems into our
inventory and use them as standard military equipment. These researches might inspire
new conceptions that could be more applicable on lower expenditures and faster. The
fight against IEDs, that claim lots of lives, is one of these issues.
Nowadays, all discovered IEDs are examined, disassembled, removed or exploded
by human power or by robots. This has claimed the lives of lots of sappers so far.
Equipping sappers or patrol vehicles with laser weapons, that can aim at IEDs, split or
destroy these suspicious devices could be very useful. Several researches are in
progress, as it is seen on Figure 11. IEDs could be destroyed without explosion,
avoiding collateral damage. They are worth being considered.24
Figure 11. Thor – High Energy Laser IED Neutralization System28
References
1. KEVIN CROWLEY: The Strategic Defense Initiative (SDI): Star Wars
http://www.coldwar.org/Articles/80s/SDI-StarWars.asp (15/05/2010)
2. GlobalSecurity.org, ERINT Extended Range Interceptor
http://www.globalsecurity.org/space/systems/erint.htm (15/05/2010)
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3. GlobalSecurity.org, HOE Homing Overlay Experiment
http://www.globalsecurity.org/space/systems/hoe.htm (15/05/2010) and
MARK WADE: HOE, http://www.astronautix.com/lvs/hoe.htm (15/05/2010)
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GlobalSecurity.org, ERIS Exoatmospheric Re-entry Vehicle Interceptor System
http://www.globalsecurity.org/space/systems/eris.htm (15/05/2010)
5 Federation of American Scientists, Ballistic Missile Defense
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GlobalSecurity.org, Space-Based Interceptor (SBI)
http://www.globalsecurity.org/space/systems/sbi.htm (15/05/2010)
6. Heritage Foundation, http://www.heritage.org/Research/NationalSecurity/upload/87946_1.pdf
(15/03/2010) and GlobalSecurity.org, Brilliant Pebbles
http://www.globalsecurity.org/space/systems/bp.htm (15/05/2010)
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GlobalSecurity.org, Boost Surveillance and Tracking System (BSTS)
http://www.globalsecurity.org/space/systems/bsts.htm (15/05/2010)
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Federation of American Scientists, Brilliant Eyes
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http://www.globalsecurity.org/space/systems/xrl.htm (15/05/2010)
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http://www.globalsecurity.org/space/systems/miracl.htm (15/05/2010)
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(15/05/2010)
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http://www.globalsecurity.org/military/systems/ship/systems/emrg.htm (15/05/2010)
15. Boeing, Airborne Laser
http://www.boeing.com/defense-space/military/abl/doc_src/ABL_overview.pdf (15/05/2010)
16. AirforceTechnologies.com, ABL YAL 1A Airborne Laser, USA
http://www.airforce-technology.com/projects/abl/ (15/05/2010)
17. Tech. Sgt. Eric M. Grill, US Air Force, Airborne laser fires tracking laser, hits target
http://www.af.mil/news/story.asp?id=123045745 (15/05/2010)
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http://www.globalsecurity.org/space/systems/abl.htm (15/05/2010)
19. GlobalSecurity.org, Advanced Tactical Laser
http://www.globalsecurity.org/military/systems/aircraft/systems/atl.htm (15/05/2010)
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http://www.weaponsblog.org/page/10/ (15/05/2010)
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http://www.spacewar.com/reports/Northrop_Grumman_Develops_Skyguard_Laser_Defense_System_For_
Local_Defense_999.html (15/03/2010)
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22. JEFFERSON MORRIS: Aviation Week, Northop Unveils Skyguard Laser Air Defense System
http://www.aviationweek.com/aw/generic/story_channel.jsp?channel=defense&id=news/LASE07136.xml
(15/05/2010)
23. WILLIAM J. BROAD: U.S. and Israel Shelved Laser as a Defense
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24. Defense Update, Thor – High Energy Laser IED Neutralization System
http://defense-update.com/products/t/thor-IED.htm (15/05/2010)
Source of pictures
Figure 1. http://www.wingsoverkansas.com/photos/sdi/200px-Sdilogo.png (15/05/2010)
Figure 2. http://www.globalsecurity.org/space/systems/images/sdi-image02.jpg (15/05/2010)
Figure 3. http://www.ausairpower.net/YAL-1A-ABL-USAF-2.jpg (15/05/2010)
Figure 4–7. YouTube print screen http://www.youtube.com/watch?v=R2eehBk_DNQ (15/05/2010)
Figure 8. http://mail2web.com/blog/wp-content/uploads/2308/53267.jpg (15/05/2010)
Figure 9. http://www.ausairpower.net/THEL-Beam-Director-Turret-1S.jpg (15/05/2010)
Figure 10. http://www.ausairpower.net/THEL-CONOPS-1S.jpg (15/05/2010)
Figure 11. http://defense-update.com/images/thor.gif (15/05/2010)
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