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Date: Mon, 04 Jul 2011 23:51:55 -0400
From: Ernest Christley <echristley@nc.rr.com>
Reply-To: echristley@att.net
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To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Subject: generator and dyno prop
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I tested the dyno-prop today.  I had been waiting to complete some 
rework on the Harly-Davidson generator I'm using.  I was trying to pass 
control back to the pilot by putting a solid-state relay inline with the 
regulator's output.  The relay appears to have either interfered with 
the proper operation of the regulator, or caused enough of a voltage 
drop to make the generator unable to charge the battery.  Either way, 
the relay is out, and a 80A fusible link is in.  I'm now getting 13.5V 
at 4000rpm.

Which leads me back to the dyno-prop.  I got lazy and didn't cut down 
the 88mm wide prop I built.  I didn't want to take the time to balance 
it again.  At 40% throttle, I had the engine up to 4000rpm (1258 at the 
prop).  That would be 26Hp if the prop was of the correct length.  I 
know I was generating more than that, but I haven't a clue how much more.

OAT was somewhere between 97* and hotter-n-hell.  The logs show the MAT 
was 103* (measured at the throttle body).  The graph of the coolant temp 
climbs at a 30 degree angle.  In 50 seconds, I went from 162* to 192*.  
That's with a blower stuck into the intake for the single radiator.  
Luckily, I think I've reached the point where I can put the cowl on, and 
start using the second radiator.