It looks like you're using an Ad Blocker.
Please white-list or disable AboveTopSecret.com in your ad-blocking tool.
Thank you.
Some features of ATS will be disabled while you continue to use an ad-blocker.
Originally posted by WestPoint23
How old is that crash? It keeps coming up again and again and wasn't the Raptor that crashed one of the prototypes?
Originally posted by W4rl0rD
2 of them crashed, one of them the YF-22 and another one the F-22. It was only known recently that the F-22 crash was due to problems with the flight software.
Garland performed his check when the two engines were started, but did not do a second check after he shut down the engines while mechanics fixed an unrelated problem. Garland thought there had been no break in electrical power to the sensors as the plane switched from engine-driven electrical generators to the auxiliary power system, according to the report.
Originally posted by Hockeyguy567
Originally posted by W4rl0rD
2 of them crashed, one of them the YF-22 and another one the F-22. It was only known recently that the F-22 crash was due to problems with the flight software.
I think it was only one, and that was six months ago
But 1 crash in 15 years, name me one other aircraft that has accomplished this feat.
Originally posted by Hockeyguy567
Originally posted by W4rl0rD
2 of them crashed, one of them the YF-22 and another one the F-22. It was only known recently that the F-22 crash was due to problems with the flight software.
I think it was only one, and that was six months ago
But 1 crash in 15 years, name me one other aircraft that has accomplished this feat.
A known defect in a ... flight-control system component is blamed for causing the crash of a $133 million US Air Force Lockheed Martin F/A-22 Raptor late last year.
The F/A-22 crashed 11s after take-off on 20 December at Nellis AFB, Nevada, the first production Raptor to be lost. The pilot ejected with the aircraft in a near-inverted attitude. The aircraft struck the end of the Nellis runway going backward. The USAF Accident Investigation Board (AIB) has traced the crash to the failure of all three rate sensor assemblies (RSA), which provide feedback on yaw, roll and pitch status to the flight-control system.
The pilot inadvertently triggered the failures of the RSA during pre-flight operations, according to the AIB report released on 8 June. The pilot shut down the engines during a maintenance check, believing the flight control systems were continuously powered by the auxiliary power unit (APU). The AIB attributed the pilot’s mistake to “ambiguous” language in the aircraft’s technical orders. In fact, the flight-control system momentarily loses power during an engine shutdown. This interruption in the power supply then is linked to a known quirk in the RSA unit, which is programmed so that it could interpret a momentary power loss as an instruction to enter test mode, which freezes or “latches” the unit, according to the AIB report.
The Air Force originally wanted to see the plane's sophisticated avionics, or electronics gear, achieve 20 hours of uninterrupted flying time without a software failure. When the plane couldn't achieve that, the Air Force changed its goal to flying five hours without a software failure. As of January, the plane could average no better than 2.7 hours.
In addition, the plane's microprocessor is an obsolete model no longer manufactured.
It's no surprise, then, that watchdog groups like the Project on Government Oversight are asking the Pentagon to put this sick puppy of a program to sleep.
.. [F/A-22, which has already cost some $40 billion and could cost another $40 billion to complete.
Development costs have risen as well -- by 127 percent, the report said.
What's more, the Air Force plans to add extra air-to-ground missions to a plane designed for air-to-air combat, which could push costs up another $8 billion or more, the report said.
The GAO also found that the F/A-22's computer-based maintenance system has suffered glitches that cause the plane to miss a significant amount of test-flying time. The Air Force had hoped to get the plane to fly nearly two hours between maintenance events by this point in the program, but has been unable to do better than an average of 30 minutes, the report said.
The avionics gear is close to flying five hours between failures, he said. While the microprocessors are outmoded, they are ample for current mission requirements, and the plane has plenty of room to add computer gear.