----- Original Message -----
From: "Jim Sower" <canarder@frontiernet.net>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Sent: Thursday, January 22, 2004 2:49 PM
Subject: [FlyRotary] Re: Torsionals


> <...  The resonant frequency for his drive is down low in RPM.  So the
rubber
> bushing actually help push it lower ...>
> OK.  I thought Tracy's was high.  So Tracy's can rattle some at low idle
so
> raise idle rpm out of that range, rubber bushings would (presumably) drive
> Tracy's all the way below idle range, or at least "soften the blow" when
it did
> rattle.
> Am I getting any warmer? ... Jim S.
>
 Red Hot, Jim.  Tracy's gear box will supposedly rattle if you get the idle
low enough, but I suspect its well below 1200 rpm and most aircraft
installations idle at or above 1200 rpm.

Ed Anderson
RV-6A N494BW Rotary Powered
Matthews, NC