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From: "Al Gietzen" <ALVentures@cox.net>
To: "'Rotary motors in aircraft'" <flyrotary@lancaironline.net>
Subject: RE: [FlyRotary] Re: combined starter alternator
Date: Wed, 4 Jun 2008 07:13:44 -0800
Message-ID: <000001c8c655$949483e0$6401a8c0@BigAl>
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For this to work as a starter, I'd need it to generate as much power as=20
a typical starter.  During cranking, I believe a typical starter will=20
draw 200A at around 11 volts.  I'm sure someone will correct me if that=20
isn't typical.  That's 2200 watts, or around 3HP.  One way to go would=20
be to adapt one of "hub motors", but the largest of the flat motors that =

I've seen are rated at only 500W (<1Hp).=20
-------------------------------

I'm going from memory here, but 2-3 years ago I did some kind of =
measurement
on the starter current (don't even remember what I did, but I think the
initial surge of current was way up there, but once spinning I was =
surprised
that it was down around 60 -80 amps.  This was during initial engine =
tests,
and perhaps the compression was low.

FWIW,

Al