Re: Undercarriage retraction on the ground

From: (Gabe Sanders)
Organization: CyberGate, Inc.
Date:         10 Oct 96 11:29:26 
References:   1
Next article
View raw article
  or MIME structure (Peter Coe) wrote:

>I was catching up on my backlog of magazines at the weekend, and in
>one of them was a short news piece about a 747 that was getting wheeled
>out of BA's Cardiff maintenance facility, when someone inadvertently
>retracted the undercarriage.  The result was $1million repair charge.
>I am rather amazed that this is possible, given that there are all sorts
>of interlocks between the undercarriage and other aircraft systems.

Most airlines have a ground sensor which will prevent the landing gear
handle from physically being moved from the down position.  It can be
overridden on most planes though.  You can also pull the ground sensor
circuit breaker which will also override this.

The next point, is most airplanes have an over center lock on at least the
main gear.  This makes it very difficult for the gear to retract on the
ground.  Many planes can have the nose gear retract.  (Actually, the nose
of the plane will lower <G>)
Gabe Sanders