From: M21208@mwvm.mitre.org
Subject: Re: CAL 747 (Re: Coffee cups in the cockpit (Re: A320 yarns))
Organization: The MITRE Corporation, McLean VA 22102
Date: Tue, 28 Jul 1992 08:38:29 GMT

In article <1992Jul27.221731.822@cactus.org>
rdd@cactus.org (Robert Dorsett) writes: (re CAL 747 upset)
 
>No, the airplane was already way out of keel by the the captain asserted
>control.  The the accident report emphasizes spatial disorientation as a
>significant factor in how long it took to get the right side up.  It
>also criticises him for not "clicking it off" at the first sign of speed
>deceleration.
>
>Also, note that the 747 is a "push it off" interface--if the pilot
>encounters considerable force (assuming it was in trim), it's likely
>that the autopilot would have shut off *then*.
>
>A more significant problem than the *control* forces were the *G* forces--
>the captain stated that at points, he was unable to raise his arms to
>grip the wheel.
>
>
<The accident report> has some comments on pilot behavior
>in automated cockpits (even of the -200 vintage); this may help sway some
>skeptics' opinions that problems don't exist. :-)
>
I don't think anybody (even Airbus Industrie) thinks cockpit problems
don't exist, but that CAL upset was a pretty gross case of bizarre pilot
behavior.  I'm fairly familiar with the incident as I was working at Oakland
Center at the time, and knew the controller involved.  As I recall, the
aircraft was at FL410 with the autopilot in speed hold mode.  Due to turbulence
the autothrottles were jockeying the power around to try to hold a constant
Mach, and the #4 engine failed to reaccelerate ("hung") as the power was
increased after a reduction.  The FE (incorrectly) announced a flameout, and
the crew began restart procedures even though Boeing stated that the maximum
restart altitude was something like FL300.  In the meantime, nobody was minding
the store while the autopilot diligently tried to hold M0.85 and heading on
three engines at FL410.  (Not for long!)  Eventually the captain decided
to get with it, but the aircraft stalled and rolled into the dead engine
almost simultaneously.  He looked at the attitude indicators, with both his and
the FO's both showing a 90 degree right bank.  Naturally, he did what any
seasoned IFR pilot would do at that point - he rejected the indications as
incorrect and started trying to recover by feel. :-(  The controller said there
was a lot of unintelligible radio traffic, and he lost radar contact at
something like FL190 because they were WAY offshore.  He genuinely thought they
had crashed.  Apparently the aircraft broke out of the clouds about then, and
the captain was able to recover visually at 11000. After going through both
Vmo and 80 knots IAS twice, pulling 6G, and ripping off the gear doors along
with about 10 feet of the horizontal stabilizer on both sides, the initial
decision was to continue to LAX. Only after the cabin crew reported injuries
did they request to land at SFO.
 
Definitely a CRM problem, along with some (literally) incredible airmanship.
What interface problems were brought out?  (I don't have the report at hand...)
>
>
>
>---
>Robert Dorsett
>rdd@cactus.org
>...cs.utexas.edu!cactus.org!rdd