posted on Aug, 8 2009 @ 02:55 PM
There is nothing unusual about the captive-carriage test. Raptor 4008 has been used for several years as a weapons integration platform for AMRAAM,
SDB, etc. Each weapon has to be mounted on its pylon in the weapons bay and carried to check loads characteristics throughout envelope expansion.
Tests are carried out with weapon bay doors in closed and open configurations during various maneuvers. This is eventually followed by stores
separation tests at various speeds.
The mishap flight was one of several runs to collect data with a missile in the left side weapons bay (SWB) during high speed maneuvers (including
rolling inverted!) with the SWB door open.
The pilot, David Cooley, was extremely experienced and highly qualified. With over 4,500 flight hours that included experience in the T-38, F-111,
F-15, F-16, and F-22, he should have been absolutely proficient in performing the anti-g strain maneuver (AGSM) to mitigate the effects of high-g
forces during flight. His most recent AGSM evaluation and training (31 January 2007), however, resulted in a rating of "average." This means that
his AGSM performance "had not been mastered fully" and that minor AGSM performance errors impacted his breathing and muscle-straining technique.
Audio recording of his high-g test mission on 23 March 2009, just a few days prior to the mishap flight, indicate that he was using improper AGSM
On the day of the mishap, Cooley made three test runs. During the first two test maneuvers, he performed an AGSM characterized by long, grunting air
exchanges at 5- to 6-second intervals. During the second run, he seemed to be having some difficulty as his AGSM seemed particularly labored and
afterward he was heard to exclaim, "Oh, man." During his third run, he did not execute a proper AGSM. He was not heard to inhale but instead made
labored grunts and groans accompanied by nearly continuous exhalation. As a result, he became susceptible to "almost g-induced loss of
consciousness," or A-LOC.
Investigators determined that "there was a progressive breakdown in his AGSM technique during each successive test maneuver." As a result of his
physical impairment due to A-LOC, Cooley lost situational awareness while the aircraft was in a steep dive. He failed to recover, ejected at high
speed, and died due to blunt-force trauma from air blast during ejection. The Accident Investigation Board concluded that the cause of the mishap was
the pilot's "adverse physiological reaction to high acceleration forces, resulting in channelized attention and loss of situational awareness."
It's easy to second guess the pilot's decision-making process with the benefit of 20/20 hindsight but it seems he should have realized that he was
setting himself up for disaster. On previous test missions, he must have been aware that he was struggling with the AGSM. During the mishap flight
particularly, he must have felt his technique slipping during the first two maneuvers. It would have been better for all concerned if he had aborted
the mission following the second run. I'm not sure if that course of action would have been career-limiting or earned him great praise but at least
he would be alive and the airplane in one piece.