Re: USAir 737 nose gear collapse

From:         ej324@cleveland.Freenet.Edu (Jack Summers)
Date:         08 Apr 94 00:16:25 PDT
Organization: Case Western Reserve University, Cleveland, Ohio (USA)
References:   1
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-> Questions for those who know: is it possible to retract the landing gear
-> when the plane is resting on it?
Yes, very easy. 737 and 727 alike
-> I would think there would be some kind of lockout to prevent such an
-> occurrence.
Yes. The landing gear handle (shaped like a wheel) will not move to either
the OFF position (hydraulics off) or the UP position without the override
trigger (shaped like a gun trigger) located on the gear handle is pulled.
I myself have first hand knowledge that if hydraulics are "on" and the gear
handle is raised with the plane on the ground to the "UP" position.  The
nose gear will retract, but because of the weight of the plane the main
gear stay down. As far as safety is concerned, as soon as the override
trigger is pulled the "Take-off" warning horn will sound. Other then that
there is nothing to prevent these kind of things from happening. However
some airlines install physical locks or "pins" when the plane is on the
ground for long periods of time (8 hours or more) that will prevent the
landing gear from coming up. If these same pins are not removed before
flight the gear can not be raised for flight, which is why most airlines do
not install them.
-> Also, related to the thread on engine mounts on wings, could a 737 make
-> a landing without nose gear the way the 727 was able
-> to? (It was quite a show on the local TV news.)
Yes it can but the engine nose cowls will contact the ground also.

>From Jack Summers