November 9, 2007: The U.S. Navy has two more
successful tests of its Aegis anti-missile system. So far, the Aegis system has
knocked down 85 percent of the missiles fired towards it. The navy modified its
Standard anti-aircraft missile system to knock down ballistic missiles. This
system, the RIM-161A, also known as the Standard Missile 3 (or SM-3) [PHOTO], has a
range of over 500 kilometers and max altitude of 160 kilometers. The Standard 3
is based on the failed anti-missile version of the Standard 2, and costs over
three million dollars each. The Standard 3 has four stages. The first two
stages boost the interceptor out of the atmosphere. The third stage fires twice
to boost the interceptor farther beyond the earth's atmosphere. Prior to each
motor firing it takes a GPS reading to correct course for approaching the
target. The fourth stage is the 20 pound LEAP kill vehicle, which uses infrared
sensors to close on the target and ram it. The Aegis system only operates from
warships (cruisers and destroyers that have been equipped with the special
software that enables the AEGIS radar system to detect and track incoming
ballistic missiles.
The U.S. has two other land based anti-missile
systems. The U.S. Army THAAD [PHOTO]
anti-ballistic- missile (ABM) system has a range of 200 kilometers, against
targets as high as 150 kilometers. THAAD is intended for short (like SCUD) or
medium range (up to 2,000 kilometer) range ballistic missiles. THAAD has been
in development for two decades. Each THAAD battery will have 24 missiles, three
launchers and a fire control communications system. This will include an X-Band
radar. The gear for each battery will cost $310 million.
The 18 foot long THAAD missiles weigh 1,400 pounds
each. This is about the same size as the Patriot anti-aircraft missile, but
twice the weight of the anti-missile version of the Patriot. Ultimately, the
army would like to buy at least 18 launchers, 1,400 missiles, and 18 radars.
THAAD is a step up from the Patriot PAC-3
anti-missile (which is an anti-aircraft missile adapted to take out incoming
missiles). The PAC-3 works, but it has limited range (20 kilometers).
