The Only Pilot to Shoot Down A Spacecraft - A Space Ace

Very impressive little kinetic kill vehicle for managing to successfully use 1980s technology.



ASM-135 ASAT

https://en.wikipedia.org/wiki/ASM-135_ASAT

The kinetic kill vehicle:



The target satellite:

Solwind

https://en.wikipedia.org/wiki/Solwind

By 1985, the satellite's batteries were degrading. This caused more and more frequent "under-voltage cutoffs", a condition where the satellite detected a low main bus voltage and automatically shut down all non-vital systems. In addition, the last of the three tape recorders failed in the spring of 1985, so data collection could only occur while the spacecraft was in contact with a ground station. A normal contact lasted only about 15 minutes, so this was a serious impediment. Special arrangements could be made to string several contacts together. As a result of these failures, an ever-increasing amount of time and network resources were spent reconfiguring the satellite for normal operation. Data collection from the few remaining payloads was severely limited. Because of the additional burden on the Air Force Satellite Control Network (e.g., extra support and antenna time at the tracking stations), discussions were already underway to terminate the mission.

This led to the satellite being chosen as a test target for an ASM-135 ASAT anti-satellite missile. The mission was extended for several weeks solely to support the test. During this final phase, the satellite was often allowed to remain in the under-voltage condition for several days at a time.
On September 13, 1985, the satellite was destroyed in orbit at 2043 UTC at 35°N 126°W with an altitude of 525 kilometres (326 mi) by an ASM-135 ASAT launched from a US Air Force F-15 Eagle fighter aircraft. The test resulted in 285 cataloged pieces of orbital debris. 1 piece of debris remained in orbit to at least May 2004, but had deorbited by 2008.

The test outraged some scientists because although five of P78-1's instruments had failed at the time of the test, two instruments remained in operation, and the satellite was what one solar physicist called "the backbone of coronal research through the last seven years".

As a young F-15 mechanic in the mid 80s; we had been told that the Eagle flew quite higher than the published 38k feet AGL, actually to the point of starvation and airstarted during free fall, but you know how urban legends get started...

Certainly a great accomplishment, but would need 4 more to officially become an “Ace”

https://en.m.wikipedia.org/wiki/Flying_ace

BABAR said:

Certainly a great accomplishment, but would need 4 more to officially become an “Ace”

https://en.m.wikipedia.org/wiki/Flying_ace

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Ah, a FACT Nazi! There's always someone who didn't get the memo. Orbiting satellites rate as 100 aircraft kills because of the difficulty factor (see pending US Space Force manual).

But, seriously, when you see how that kinetic kill vehicle worked with such limited tech, it blows the mind. A thing of beauty.

Yes I remember that! So Cool. But I always remembered that the service ceiling was 65,000' (W/pressure suit req'd. above a certain alt.). Didn't "Streak Eagle" Go above 100,000'?

TALON said:

Yes I remember that! So Cool. But I always remembered that the service ceiling was 65,000' (W/pressure suit req'd. above a certain alt.). Didn't "Streak Eagle" Go above 100,000'?

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Yes, it reached almost 103kft, according to Boeing.
https://www.boeing.com/history/products/f-15-eagle.page

The ASAT was released at 38kft. At this point the F-15A was performing a 65% climb at Mach 0.934. If the Eagle would have simply continued ballistically from there on, it would have gained nearly another 14kft before reaching apogee.

In simple terms of energy, The F-15 could have imparted more of it to the rocket by releasing it at its maximum service altitude while in level flight. For rockets however, kinetic energy imparted to it before ignition will usually have a bigger effect than potential energy (E_pot = mgh scales linearly but E_kin = m*v^2/2 scales quadratically).
Also, the booster of the rocket originated from the AGM-69 SRAM, a nuclear armed air to ground missile, which was certainly not optimized for maneuverability at high altitude, so releasing it while pointing in roughly the right direction was important to get an efficient trajectory too.


Reinhard

F15/ASAT operations are described dramatically (no idea how accurately) in Tom Clancy's "Red Storm Rising".