ITV 1, 2

ITV 1 [USAF]

ITV 1, 2 in launch configuration [USAF]

After the successful intercept of the Solwind satellite by an ASAT (ASM-135) missile, the USAF launched two ITV (Instrumented Target Vehicle) dedicated target satellites. They consisted of a cylindrical body and an inflatable balloon, which carried impact detectors to assess the impact of the kinetic ASAT kill vehicle (MHV).

The ITV balloons were inflated by a hydrazine monopropellant / ruthenium catalyst gas generator. This was calculated to inflate, heat and maintain the Kevlar balloon at the desired infrared signature required for the ASAT homing vehicle's sensor.

Data from a variety of sensors on the external surface of the balloon were telemetered back to ground stations. The few frames of data that would be received between inflation and intercept allowed the balloon's infrared signature and the geometry of the impact by the interceptor to be determined.

Temperature sensors were embedded in the Kevlar surface at various points. Magnetometers allowed determination of the attitude of the ITV. A grid of break-wires on the surface allowed the location of any impact to be determined. An omni directional low-power continuous wave radar Miss Distance Indicator sent back data in case the hit-to-kill interceptor did not impact the target. This allowed misses out to around 30 m to be determined; misses beyond that range could be analyzed by post-test radar data.

Battery powered, the balloon satellite remained inert and uninflated in orbital storage until the inflation command was transmitted to it. This would only come minutes before the intercept test, and was given as the satellite passed over a Hawaiian ground station. This would set the target up for an intercept over the California coast by an ASAT launched by an F-15A from Edwards AFB.

Both satellites were launched simultaneously on a Scout-G1 rocket. There might be the possibility, that the launch vehicle underperformed, resulting in the elliptical orbit. As a congressional ban on testing ASAT weapons was imposed after the Solwind test, it was decided to keep the satellites dormant and uninflated in orbit. Finally, permission was granted to test the inflation system. Only ITV-2 was inflated in space on 18 December 1986. It is unclear if ITV-1 failed to inflate or if it stayed uninflated intentionally. Both satellites reentered without being used as targets. The inflated ITV-2 target decayed after 604 days (on 9 Aug 1987) and the uninflated ITV-1 target decayed after 1245 days (on 11 May 1989).