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C-17A Crash Video Surfaces

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deathfromafar

Charter Member
Not sure if this has been posted here before as I couldn't find it on search. This is the USAF video of the incident. It is very obvious the pilot handled to C-17 too aggressively and eventually stalled it turning too steeply and losing control. It parallels the B-52H crash at Fairchild AFB in 1994. Quite tragic. The editors clipped the impact segment but you see the majority of the incident.

http://www.youtube.com/watch?v=aaWI8MNL4Do&feature=related
 
Obviously, the pilot got into that "I can do anything with this" frame of mind and forgot to not exceed the banking limits on the plane at that low of an altitude and airspeed. Very much like the footage of the B-52 from years ago. Very sad for those on board and those on the ground watching.
 
The maneuvers looked awfully aggressive to me but looking back at footage I shot of the same type of demo at a different base, it is about the same. Some folks from the C-17 community claim the pilot was within the approved maneuvers but that the flap retraction and more importantly the slat retraction before the final turn cost them about 30+ % lift at that speed and bank angle. When he started that final pull, the right wing fully stalled according to the accident report(cited in text by the same C-17 community members).

I hate seeing accidents of any kind but especially when an aircraft goes down. I was a witness to a fatal aircraft accident years ago and it sent a chill down my spine I have never forgotten.
 
The Fairchild AFB B-52 crash repeated. :frown: As the plane begins its descent toward the ground you see basically the entire overhead planform of the aircraft, it has to be banked nearly 90 degrees from wings-level. Just because you can do a near 45-degree take-off climb in a C-17 doesn't mean you can do 90-degree angle of bank.
 
Like with the Bud Holland crash from a few years ago, I'm sure the rest of the C-17 community will learn from this accident.
 
deathfromafar said:
The maneuvers looked awfully aggressive to me but looking back at footage I shot of the same type of demo at a different base, it is about the same. Some folks from the C-17 community claim the pilot was within the approved maneuvers but that the flap retraction and more importantly the slat retraction before the final turn cost them about 30+ % lift at that speed and bank angle. When he started that final pull, the right wing fully stalled according to the accident report(cited in text by the same C-17 community members).

I hate seeing accidents of any kind but especially when an aircraft goes down. I was a witness to a fatal aircraft accident years ago and it sent a chill down my spine I have never forgotten.
Click to expand...

Offical USAF accident investigation board results are that the accident was due to pilot error.
--> http://www.af.mil/news/story.asp?id=123234579
 
it doesnt look that bad .. they really threw around the one that was at RIAT this year, maybe just pulled back that little bit to hard rather than banked to far?
 
It should be remembered that this particular flight was a final practice for the annual JBER (Joint Base Elmendorf-Richardson) air show, “Arctic Thunder”, and that while not excusing poor pilotage it may go a ways toward understanding why the pilot in command was able to justify, in his own mind, pushing the envelope so far. Also, if I have understood the coverage of the incident correctly, two of the three pilots on board the aircraft were relatively low time in this type.
 
I read the full report from the link Panther posted. Besides the typical upper echelon command CYA catch-all's in the report, it seems that like past accidents, there was a culture of arrogance/overconfidence and non-compliance to regulatory guidelines regarding both regular C-17 flight ops and demo envelopes. More than one C-17 pilot has flown the type in this manner and this was the only time the overconfidence came back to bite them. The pilot was well qualified having 3,251 total C-17A flight hours including 974 Instructor Hours and 124 Evaluator Hours.

Generally, the Mishap Pilot had taught student Demo Pilots to ignore stall warnings as they were "erroneous" in various parts of the demo envelope. Also, many standard procedure flows/ "Call Outs" were routinely pushed aside in demo flights. It should be noted that no two C-17 demo pilots adhered to specific procedures/flows.

The normal bank limitations are 45 degrees and no more than 40 degree nose up pitch initial max climb profile to 1500 ft AGL. These parameters were violated with the Mishap Pilot bunting over the nose at lower than 1500 ft AGL and utilizing 60 degree banks.

Also contributing to the accident was the retraction of the flaps and slats "on speed". The clean wing configuration led to a high loss of lift during the final turn.

Last but not least, the C-17A has both a Stall Protection System and a Deep Stall Protection AoA Limiter System(ALS). The ALS when active will limit the command nose up elevator position.
In this accident, when the ALS became active, the elevator surface movements decreased lessening the effectiveness of the Mishap Pilot's aft stick inputs.

The part about the ALS system bothers me. I will be willing to bet there are major issues with that system both Boeing and the Air Force do not want to admit publicly. Albeit the Pilot screwed up, the other factors involved go to show that safety automation are not fool proof and are not perfect by any means. The old saying I remember well: Automation is good enough to kill you!
 
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