Re: RAT for CVR

Date:         05 Oct 98 00:26:14 
From:         "David G. Davidson" <>
Organization: EarthLink Network, Inc.
References:   1 2
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  or MIME structure wrote:
> On the subject of power availability to the DFDR or the CVR in the back
> end of the aeroplane, there is a source available, the APU battery.
> This assisted in the start up of the APU, is fully charged and has no
> other purpose as far as I can see once the APU is running and providing
> power to the buses

The only airplanes that I'm aware of that have a dedicated battery for the
APU are the 757 and 767. All other airplanes (DC-9, MD-88, MD-90,
727,737,L-1011 ) that I've worked with have only one battery that 's used
for emergency power as well as starting the APU. I have worked on DC-10s
but I can't recall how the battery situation was on that airplane. I know
that the A310 has more than one battery but again I don't recall how that
was wired up.