Failure - Interactions
Much more on this case -- In-progress, standby:
pdf is short, 772KB
New York Times, March 15, 1959, p86:
"the airline has used only supervisory personnel to fly its jet . . .
"Pan Am Training . . . regular line pilots . . . dispute settled last month."
Testimony, Flight Engineer, George Sinsky,
Sound of Mach Warning,
unable to raise arms ...
Horizontal Stabilizer TRIMMED full-nose-down ...
manually cranked Horiz-Stab' to normal position,
Testimony of Sam Peters,
who sat as co-pilot (right-seat, SIC)
22z Heading change, to LEFT, "posted" by Nav'.
Autopilot Turn Knob -- turn OK.
Buffeting, caused panel light failure -- [rolled right]...
Captains Horizon had tumbled ...
Co-Pilot used Control Wheel -- left aileron, and Rudder,
G-loads, "immobilized", severe buffeting,
Captain Lynch returned ... cut power ...
Horizontal Stabilizer TRIM ... position showed nose-down ...
F/E manually cranked Horiz-Stab TRIM
(cranked Trim-Wheel ) ... pull-out ... climb ...
heavy pounding and buffet at 6000-feet,
zoomed nose-up, climb,
control by 9000-feet . . .
After recovery, "heavy" right rudder needed . . .
Captain Waldo Lynch, testimony:
increased NOISE level,
Lynch re-entered cockpit,
"slammed" Thrust Levers to IDLE,
gyro-horizon had tumbled,
Airspeed past 400 KIAS,
Altitude passing 17,000-feet,
Electric Pitch-Trim thumb-switch INOP'
Prior history of Autopilot trip-OFF.
Other pilots had not reported -- few "disconnects"
had been reported before the mishap.
After the mishap-dive, on Feb' 6th,
pilots entry in aircraft logbook:
with no warning-light.
Uncertainty about status of Autopilot,
just prior to the INITIAL upset:
Not ENGAGED? Disconnected?
No aural nor visual annunciation
that the Autopilot had Disengaged.
London to Gander, CRZ,
35,000-feet, 0.82 Mach,
GWt 195,000 (pounds),
~ 2200 Z . . .
On Mar' 11th and 12th 1959,
C.A.B. heard "depositions" in New York,
with later depositions in Seattle and L.A.
New York Times, Feb' 5th, 1959, p20:
Night, step-climbed to 35,000-feet, over storm,
standing in forward passenger-cabin,
shaking, thrown to floor,
crawled back to pilot's cockpit-seat, recovered ...
. . . during the captain's absence from the cockpit
the autopilot disengaged and
the copilot did not detect . . .
a steep nosedown right spiral. . . .
it entered this maneuver gradually without any abrupt movements. . . .
during the hours of darkness,
the autopilot disengage warning light … failed . . .
[C.A.B.'s AAR, p8, "Analysis"].