Re: Are Two Engine 757 & 767 Jets Dangerous?

Date:         27 Dec 96 13:32:18 
From: (Don Stokes)
Organization: Victoria University of Wellington
References:   1 2 3
Followups:    1
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In article <>,
Karl Swartz <kls@ohare.Chicago.COM> wrote:
>The El Al crash in Amsterdam, as well as the 1991 China Air crash near
>Taipei (both 747-200Fs) suggest that losing two during climb may not
>be recoverable -- I'm not sure if any of the wing damage in El Al was
>significant with regard to control of the plane, and I know even less
>of the details of the China Air crash.
>On the other hand, United 811, the 747-100 which lost the cargo door,
>shows that a 747 *can* recover and return safely after losing two
>engines at higher altitudes (though in that case still during climb).

On the other hand, the El Al flight probably would have made it if
high-rise apartments weren't in the way, and UA811 probably wouldn't have
if they were... in both cases the aircraft were heavily loaded and unable
to maintain level flight, let alone climb, with two engines out on the
same side.  HNL is a somewhat easier approach...

(I don't know the details ofthe China Air crash either.)

Which raises the question of the requirement to be able to limp home --
would UA811 have made it back to HNL if the accident had occured an hour
later -- would it have burned enough fuel to allow level flight?  Would
there always have been a glide slope for the given weight at the time
that would have got them home with two engines out on the same side?

Clearly, the El Al flight didn't have enough margin -- are the rules
different for cargo flights?

Don Stokes, Network Manager, Victoria University of Wellington, New Zealand. +64 4 495-5052 Fax+64 4 471-5386