Re: Peruvian 757 crash

From:         dtmedin@cca.rockwell.com (David T. Medin)
Organization: Rockwell Avionics - Collins, Cedar Rapids, IA
Date:         06 Nov 96 05:12:36 
References:   1
Next article
View raw article
  or MIME structure


In article <airliners.1996.2270@ohare.Chicago.COM>, Jonathan Griffitts <jcg@qadas.com> writes:
|> I've been lurking, waiting to see any more information on the Peruvian
|> 757 crash a couple of weeks ago.  All I've seen so far is very sketchy
|> and self-contradictory information from the newspaper.
|>
|> >From what I can tell, it would appear that the 757 suffered some kind of
|> major failure in the electronics.  The pilot was quoted as saying that
|> "the computers are going crazy" and that he did not know where he was.
|> He pleaded for a guide plane to help him navigate back to the airport.
|> Then somehow the plane went into the water.
|>
|> This sounds like it COULD be the ultimate glass-cockpit horror story:
|> they suffered an electrical or electronic failure that was so complete
|> that it left the plane uncontrollable.  Is this is the event that the
|> glass-cockpit opponents have been predicting?
|>
|> However I would be quicker to believe that the computers did something
|> unexpected, and the pilots were so distracted that they forgot about
|> flying the airplane.  Or perhaps they got disoriented under night/low-
|> visibility conditions and lost control that way.
|>
|> Is there any more information out there yet?

There are several things to consider with the glass cockpit horror
story, though. First, you have the standby instruments which run from
a DC (battery) bus, which even if you lose the primary flight
displays, you can still rely on. These instruments typically have
alternate air data inputs from the primary systems to eliminate common
points of failure.

The other is that the flight controls are partitioned systems from the
displays, so even if the flight displays all went south, there would
have to be a more common or drastic failure to take the flight
controls with it.

I, too, am interested in hearing what becomes of this incident.
--
-------------------------------------------------------------------
       David Medin            Phone: (319) 295-1862
   Rockwell Collins ATD	      Internet:
     Cedar Rapids, IA	   	dtmedin@cca.rockwell.com