High Energy Laser Systems
The White Sands Missile Range High
Energy Laser Systems Test Facility (HELSTF) was established
to support the test and evaluation of high energy laser
systems, subsystems and components, and to support the conduct
of damage and vulnerability tests on materials, components,
subsystems and systems.
Background
During the 1970s, the need became apparent for a test
site to support the Department of Defense's (DoD) continued
development of lasers as weapon systems. Several test
ranges were considered, with White Sands being selected
as the site and the resulting facility being known as
HELSTF.
The first principal user
of the facility was to have been the Navy SEALITE program,
a self-defense lethality demonstration using the Mid-Infrared
Advanced Chemical Laser (MIRACL). Congress canceled the
SEALITE program in the fall of 1983 and directed the MIRACL
be installed at HELSTF to support a variety of tests for
DoD.
HELSTF also houses the
Excimer Raman-Shifted Laser Device (EMRLD), a smaller
device developed by the Air Force. The site will serve
as the home base for the Army's Pulsed Laser Vulnerability
Test System (PLVTS), as well as other lasers to support
the Army's tactical and strategic systems development.
HELSTF represents an approximate
$800 million investment, with about $80 million of that
in military construction funds.
HELSTF became operational
on September 6, 1985 when the Air Force conducted the
first Lethality and Target Hardening (LTH-l) program test
for the Strategic Defense Initiative Organization (SDIO).
Since then HELSTF has provided test support to DoD, industry
and foreign governments under appropriate agreements.
Management
The Secretary of the Army directed the transfer of HELSTF
management to the U.S. Army Space and Missile Command
(SMDC) by October 1, 1990. Prior to that, the facility
was under the command of Commander, White Sands Missile
Range. Management of HELSTF by SMDC will allow for expansion
of the HELSTF mission to support Army and DoD research
and development efforts, as well as retain its capabilities
for performing test and evaluation support.
Primary support for operation
and maintenance of the SMDC-managed facility is currently
provided by Lockheed Engineering and Science Company (LESC).
The Navy is responsible for the operation and maintenance
of the MIRACL and the SEALITE Beam Director through its
contractors, TRW and Hughes Aircraft. The EMRLD device
is the management responsibility of the Air Force.
Facilities
Mid-Infrared Advanced Chemical Laser
The MIRACL was built by
TRW for the Navy to show that linear cavity chemical laser
technology could be scaled to multi-megawatt power levels.
The device is a continuous wave (CW) deuterium fluoride
(DF) chemical laser which operates at a wavelength of
3.8 microns. Its continuous power output is the highest
yet achieved by any U.S. laser.
The laser is basically
an exotic rocket engine composed of individual module
assemblies each having many nozzle blades. The modules
are fed from an upstream combustion chamber and are designed
to produce an optically uniform downstream flow field
as a lasing medium. A gaseous oxidizer is reacted with
a fuel mixture and ignited in the combustor to produce
fluorine. Deuterium is injected into the flow to chemically
combine with the fluorine atoms and produce the required
population of excited DF molecules upon which lasing is
based.
SEALITE Beam Director
The SEALITE Beam Director
(SLBD) is a high precision pointer-tracker system built
for the Navy by Hughes Aircraft Company. It is designed
to accept the MIRACL beam and focus it onto a specific
point on a flying target. The beam director consists of
a servo control system, an elaborate optical system and
a computer controller. The servo system contains numerous
electronic control loops, a large coarse gimbal structure,
a tracking sensor and a stabilized inertial reference
platform.
High Energy Laser Experimental
Test System
The MIRACL, when operated
with the beam director, comprises the High Energy Laser
Experimental Test System (HELETS). The Low-Power and High-Power
Dynamic Test series were completed in 1988. These series
characterized the HELETS total optical quality, power
on target and dynamic pointing stability.
Beam Transfer Area
The beam Transfer Area
(BTA), essentially a laser beam switch yard, allows HELSTF
to move the MIRACL beam to a variety of indoor and down
range test sites. The BTA is used instead of the HELETS
for damage and vulnerability testing. Inside the BTA are
two fast shutters capable of turning the MIRACL's continuous
wave beam on and off within five milliseconds. The shutters
work in conjunction with the facility's target cassette
indexer and down-range mirrors to provide precise laser
beam exposures to test materials. Switch mirrors in the
BTA allow testing both inside and down range during a
single test run.
Effects Test Area
The Effects Test Area (ETA)
is an indoor laboratory used for testing damage and vulnerability
of materials and systems. The ETA consists of a target
cassette indexer, laser optics and test instrumentation.
The target cassette indexer
inserts the samples into the beam path as the fast shutters
turn the beam on and off. It is capable of handling up
to 60 samples, each 10-inch by 10-inch by 2.5-inch, or
30 samples, each 10 inch by l0-inch by 5-inch.
The TMHS is equipped with
a side wall wind tunnel capable of providing a variety
of gas flows and speeds across the target surface. Gases
which can be used are air, nitrogen and other inert gases.
Down-Range Facilities
Located down range is Test
Cell B or the hazardous test site. This test site uses
a slewable, high-power optical train to irradiate various
targets on the test pad. The MIRACL beam is sent to Test
Cell B via optics in the BTA. Tests demonstrated the ability
to irradiate more than 45 target samples during a single
run. New Test Cell a optics provide better beam quality
and fewer beam distortions, as well as faster beam slewing
and scanning. For explosive targets, Test Cell B is rated
for the equivalent of 20,000 pounds of TNT. Other down-range
test sites include a two kilometer test site and a moving
target test track.
Large Vacuum Chamber
A 50-foot diameter Large
Vacuum Chamber (LVC) was completed in October 1988. The
LVC is designed to accept materials up to half the size
of the space shuttle bay and produce vacuums equivalent
to 300,000 feet in altitude.
What makes the HELSTF LVC
unique is the Pressure Staging Assembly Facility (PSAF)
which allows transporting the MIRACL beam from atmospheric
pressures to the LVC extreme vacuums via a special Zinc
Selinide material window. Currently this material window
has performance limitations that restrict the run time
of the laser through the window. A new window is being
developed which should not restrict the laser run time.
Test Instrumentation
Available at all HELSTF
test sites is a wide variety of diagnostic and test instrumentation,
plus motion picture, fixed camera and video camera support.
The High Energy Laser Data Acquisition and Processing
System (HELDAPS) acquires the data provided by the instrumentation
and processes it into the form required by the tester.
Data is normally provided to the user in 12- and 24-hour
packages after each test.
Pulsed Laser Vulnerability
Test System
The Pulsed Laser Vulnerability
Test System (PLVTS) is a transportable Army system that
will use a threat surrogate laser device to test the vulnerability
and susceptibility of U.S. tactical systems to expected
tactical battlefield directed energy threats. The system
was developed by Rockwell Power System for the Army. Although
transportable, PLVTS is housed at Test Cell 3 when at
HELSTF.
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