Re: Mystery over 1992 El-Al crash

Date:         30 Nov 98 03:07:30 
Organization: Unconfigured
References:   1 2 3
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G'day, wrote:
>A media beat up. The aeroplane will fly on two engines so why not fly to an
>aerodrome and land rather than to a lake and ditch.

My understanding was that the aircraft would fly with 2 engines shut
down, as opposed to 2 engines on the same side missing (at the weight
in question).  The associated loss of the No.3 & No.4 hydraulic
systems in an extreme assymetric configuration was not considered when
designing the aircraft to cope with 2 engines out on the same side.
In a 2 engine out situation, the No.3 & No.4 ADP would function, even
if the engine was not windmilling to power the EDP.  The reduction in
rudder authority from the loss of half the hydraulic systems means
that the situtation you describe below would appear inevitable,
considering the speed the aircraft was at when the engines departed.

>As with any asymmetric flying the Vmca or in this case the Vmca2 must be
>adhered too. To slow below it means loss of rudder directional control and
>yaw. Applying  power then to regain the speed exacebates the problem. If I
>recall this became the crux of his problem with an attempted go around.

Of course, please tell me how my understanding is in error.

Paul Saccani
Kuala Lumpur