Re: SR111 findings

Date:         Sat, 12 Dec 1998 22:37:53 EDT
Organization: Netcom Online Communications Services (408-241-9760 login: guest)
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In article <>; "Thomas J. Bueld" <>; writes:
>;3. Fuel is transfered by electrical (AC) fuel pumps to the respective
>;engines. the center engine is mounted above the fuel tank level. so its
>;fuel supply depends on electric (AC) power supply to the pumps, while the
>;wing mounted engines will continue runnning by gravity fuel supply in the
>;event of electrical power loss. In consequence a failed center engine is
>;an indication of electrical (AC) power failure of the aircraft.

On Boeing aircraft, the manifold providing fuel under pressure to the
engine is typically driven by two or more AC pumps powered by AC systems not
coupled to that engine.  Depending on the pump, the AC systems involved
can include both primary AC busses as well as the essential power bus.

On the 727, all three engines, which are mounted above the fuel tanks, have
a suction-feed system, in addition to the AC pumps.  The 737, 747, and DC-9
work much the same way.

Now, nothing would surprise me when it comes to the DC-10 or its descendant,
but I have a big problem believing that engine failure is used as an
indicator of AC failure.

Is your comment based on familiarity with the actual aircraft type?

Robert Dorsett                         Moderator, sci.aeronautics.simulation               

           "Bother," said Pooh when his engine quit on take-off.