"Ben Jackson" wrote in message
...
On 2007-02-03, Matt Barrow wrote:
"Ben Jackson" wrote in message
http://www.ntsb.gov/ntsb/brief.asp?e...24X01192&key=1
What really stunned me about that report is that the probable cause
chain does not end with the pilot.
Okay...I had a lot of "medicine" last night; could you elaborate on that?
Almost every NTSB report that involves the failure of an airplane system
that could have been mitigated by the pilot, no matter how terrible the
user interface, is ultimately blamed on the pilot. In that particular
report there's even a discussion of the steps the pilot could have taken
to fix the runaway trim condition, so I didn't expect them to give the
pilot any slack just because he was busy using both hands and all his
strength to keep the nose up...
/quote
The investigation revealed that the K6 relay failure would constitute a
single-point type failure in the electric pitch trim system.
(Key)
Pulling the circuit breaker, which is called for by the checklist in the
event of a trim runaway, would have arrested the trim movement _provided_
(emphasis mine) the circuit breaker was opened prior to the trim reaching
its stop.
Further examination of the system revealed that the autopilot autopilot/trim
disengage switch would not have disengaged the electric trim motor during
the type of failure experienced in the accident airplane.
/end
Sounds like he had just a few seconds to react, and the first order of
business was to disengage the AP, the he had to identify the problem as
runaway trim.
Not bad, for an 80 year old fart.