Bulent Aliev wrote:

[The Canard Aviators's Mailing list]

VACUUM PUMPS

I was looking up vacuum pumps, idly wondering which of the kids I'd have
to hawk to afford a commercial unit when my eyes fell on a nifty little
item.  Seems McM-C sells a 12 volt compressor / vacuum pump that
develops 14.8" of vacuum, consumes but 340 milliamps of power, is a
small 3.07" x 1.18" x 2.09", is rated for continuous operation, and
costs a whopping $114.00.  There has been more than one posting recently
about the unreliability of aircraft vacuum pumps.  For less than the
cost of one Sigma-Tek ( or whatever ) you could buy four of these babies
hook them up through a rotary switch and some check valves and have
quadruple redundancy.  If one of them goes south, pitch it overboard and
settle for triple redundancy!  Check them out on page 759 of Catalog
106.

Bill Freeman wrote:

  I doubt it had enough capacity to run your gyros if it only
draws 340 mA.    The commercially available  electrically
driven systems have big motors, probably draw 4-8 amps,
just judging from the motor size.  You need to find out what
the std cubic ft per minute rating of the aircraft pump is and
then compare this to your McM-C pump.  Hope it works,
doubt it.   As with so many other things, if it was this easy . . .

Bill

 
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