> http://edition.cnn.com/2008/US/06/06/crash.ap/index.html

Has been discussed on ARocket recently, not surprisingly.

Russell says:

1.    Document identified problems
2.    Ensure appropriate responses are appropriately 
promulgated.
3.    Yeah, right.

________

Summary:    5% of the USA's B2 penetration bomber fleet (1 
aircraft) was lost on Guam on Feb 23rd 2008 when the bomber 
rotated early then went into a high angle of attack mode and 
then had inadequate airspeed for the crew to be able to 
present it stalling while only metres above the runway. The 
aircraft settled to the left and the crew ejected * as the 
left wingtip touched the ground. "Grassy knoll" quality 
video available via the above link. Both crew survived. The 
1.4 $B aircraft was a total loss. Only B2 lost so far in 20+ 
years.

* From casual look at video

The most important point not mentioned above is that the 
crash was caused by faulty air speed data due to moisture in 
a sensor system AND that the problem had been known about 
for two years AND a means of removing the problem at startup 
was known.

    "The sensors measure air pressure to help calculate 
everything from airspeed to altitude. Because of the bad 
data, flight computers had inaccurate airspeed and wrongly 
indicated a downward angle, which contributed to an early 
rotation and uncontrolled 30-degree pitch up. Carpenter said 
the lack of altitude and airspeed prevented the pilots from 
correcting the aircraft."

and

    ... "However, a technique learned by some two years ago 
that had gone widely unknown and unadopted probably would 
have prevented the crash, Carpenter said. The technique 
essentially heats the sensors and evaporates any moisture 
before data calibrations. "This technique was never 
formalized in a technical order change or captured in 
'lessons learned' reports. Hence, only some pilots and some 
maintenance technicians knew of the suggestion," according 
to Carpenter's executive summary of the accident. The report 
said, "The human factor of communicating critical 
information was a contributing factor to this mishap."

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