is designed to defend U.S. troops, allied forces, population
centers and critical infrastructure against short- to intermediate
range ballistic missiles. THAAD comprises a fire control and
communications system, interceptors, launchers and a radar.
The THAAD interceptor uses hit-to-kill technology to destroy
targets, and is the only weapon system that engages threat ballistic
missiles at both endo- and exo-atmospheric altitudes. The contract
includes funding for 48 interceptors, six launchers and two
fire control and communications units.
In 2006 the THAAD weapon system transitioned from
development to production, and conducted two successful flight
tests. The first test demonstrated the entire weapon system,
utilizing all major elements of the system and proving its capability.
A second test last year resulted in the intercept of a Hera
The THAAD System:
The THAAD interceptor uses hit-to-kill technology
to destroy targets, and is the only weapon system that engages
threat ballistic missiles at both endo- and exo-atmospheric
altitudes. The "kill vehicle" uses an infrared (thermal)
imaging seeker, built by BAE Systems, to detect and track the
targeted warhead at the terminal phase, when the THAAD is homing
in for a 'Hit to Kill' maneuver. The kill vehicle maintains
maneuverability using the Divert and Attitude Control System
(DACS) supplied by from Pratt & Whitney Rocketdyne (PWR).
The system provided roll control of the missile during booster
flyout and maneuver of the kill vehicle using small, liquid-fueled
thrusters that allow the interceptor to alter direction and
Another key element in the system is the phased
array radar, developed by Raytheon IDS. The THAAD radar is capable
of search, threat detection, classification, discrimination
and precision tracking at extremely long ranges. This radar
acquires the target, discriminates the lethal object from other
debris, provides track and discrimination data to the fire control
which engages the target and initializes the launch sequence.
Target acquisition and tracking are also performed by the interceptor's
seeker, through the terminal phase of the flight. The system
communicated with the in-flight THAAD interceptor providing
target updates during the flight.
PMRF is the world's largest instrumented multi-environment range
capable of supporting surface, subsurface, air, and space operations
simultaneously. The THAAD program began flight testing in November
2005 at White Sands Missile Range (WSMR), NM. Three successful
THAAD tests were conducted at WSMR including the intercept of
a unitary target in July 2006. The first tests conducted in
and April) were the first in a series of intercepts to be tested
at the Pacific Range (PMRF) scheduled for the next 24 months
leading to operational fielding in fiscal year 2009.