Two of the pilots said the software glitch
should have been caught in engineering reviews
while the Osprey was being tested, before it
left the experimental stage. In the December
crash, they said, the software should have
triggered a backup hydraulics system after a
primary system began to leak. Instead, the
software worsened the situation each time the
pilot hit a reset button.

Hydraulics power the tilt of the engines and the
pitch of the propellers, while the software helps
the pilot control the aircraft. Both are vital to
keep the aircraft flying. The two pilots said their report raised broader
questions about how such a serious software glitch
got into an aircraft that was in regular use. They
said their draft of the report recommended that the
Pentagon and the Osprey's manufacturers "address the
process failure . . . that allowed that to make it
through."

Philly.com

-- spider (spider0@usa.net), April 05, 2001