737 Crash in Panama

From:         sane@deil.unx.dec.com (P. B. (Nitin) Sane)
Organization: Digital Equipment (India) Ltd, Bombay, India.
Date:         22 Jul 94 12:44:02 
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Hi,

	Yesterday on Nova (PBS), they showed a feature on
investigation of a crash of 737 in Panamian jungles. 

	For those, who did not watch the program :

	A 737 on a routine flight disappeared during night time over
the jungles in Panama. A wrekage was found next day scattered over a
large expanse of the jungle. All bodies found were naked suggesting a
free fall from a high altitude. CVR was non-functional at the time of
the crash, so no clue to what happened in the cockpit during final
moments of the flight. DFDR showed data which was very inconsistent
with the behaviour of the type of aircraft (ie - 737). NTSB team
concluded/proved that cause of the crash was a faulty connection in
one of the wire leading to the ATI/artificial horizon in front of the
pilot. Further, co-pilot was also looking at the faulty reading in
front of him as the overhead switch was to show faulty gyro active.
(They failed to check the reading with stand-by).

	According to reading on DFDR, flight recovered from the 15 deg
left turn, but at that point, ATI remained stuck and as a result,
cockpit crew over corrected the plane to right until, it became almost
inverted, nose-dived and at about 10,000 ft broke up due to gravity. 

	Now, my question is, how could a pilot (with 35 years of
experience behind him) did not notice any thing wrong until it was too
late ??? Won't he have known when the a/c turned more than, say 30
deg, to right and ATI kept showing 15 deg left bank??? How did such an
experienced pilot did not realize an excessive turn to right??? (Well,
I certainly notice if somebody tilts me more than about 30 deg from
vertical, and I am not even a pilot :-) ))

----- Nitin