Saturday, September 8, 2012

The F-15 ASM-135 ASAT Program





"The ASM-135 was designed to be launched from an F-15A in a supersonic zoom climb. The F-15's mission computer and heads-up display were modified to provide steering directions for the pilot.

"On 21 December 1982, an F-15A was used to perform the first captive carry ASM-135 test flight from the Air Force Flight Test Center, Edwards AFB, California in the United States. On 20 August 1985 President Reagan authorized a test against a satellite. The test was delayed to provide notice to the United States Congress. The target was the Solwind P78-1, an orbiting solar observatory that was launched on 24 February 1979.

"On 13 September 1985, Maj. Wilbert D. "Doug" Pearson, flying the "Celestial Eagle" F-15A 76-0084 launched an ASM-135 ASAT about 200 miles (322 km) west of Vandenberg Air Force Base and destroyed the Solwind P78-1 satellite flying at an altitude of 345 miles (555 km). Prior to the launch the F-15 flying at Mach 1.22 executed a 3.8g zoom climb at an angle of 65 degrees. The ASM-135 ASAT was automatically launched at 38,100 ft while the F-15 was flying at Mach .934. The 30 lb (13.6 kg) MHV collided with the 2,000 lb (907 kg) Solwind P78-1 satellite at closing velocity of 15,000 mph (24,140 km/h).

"NASA learned of U.S. Air Force plans for the Solwind ASAT test in July 1985. NASA modeled the effects of the test. This model determined that debris produced would still be in orbit in the 1990s. It would force NASA to enhance debris shielding for its planned space station. Earlier the U.S. Air Force and NASA had worked together to develop a Scout-launched target vehicle for ASAT experiments. NASA advised the U.S. Air Force on how to conduct the ASAT test to avoid producing long-lived debris. However, congressional restrictions on ASAT tests intervened. In order to complete an ASAT test before an expected Congressional ban took effect (as it did in October 1985), the DoD determined to use the existing Solwind astrophysics satellite as a target. NASA worked with the DoD to monitor the effects of the tests using two orbital debris telescopes and a reentry radar deployed to Alaska. NASA assumed the torn metal would be bright. Surprisingly, the Solwind pieces turned out to appear so dark as to be almost undetectable. Only two pieces were seen. NASA Scientists theorized that the unexpected Solwind darkening was due to carbonization of organic compounds in the target satellite; that is, when the kinetic energy of the projectile became heat energy on impact, the plastics inside Solwind vaporized and condensed on the metal pieces as soot."

From flickr via TORD.

Wikipedia page
The F-15 ASAT story

Also check out my NOTS EV-1 Pilot (NOTSnik) posts:
1 - 2 - 3 - 4

No comments: