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Date: Sun, 23 Jan 2005 02:47:59 -0600
From: "Phil White" <philwhite9@aol.com>
Subject: Re: [FlyRotary] Re: Dynos II
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
In-Reply-To: <list-617649@logan.com>
Message-ID: <41F364BF.2010403@aol.com>
References:  <list-617649@logan.com>
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Why not make a "chassis dyno" out of our fuselage?
    Install the engine with all its accessories and prop, cooling system, 
etc.  Attach tail to your car/truck to prevent movement, place scales 
under the main gear.  Have an assistant collect weight differential 
readings at various rpm's.  With accurate measurement of the track 
distance, the scale readings can be converted to ft-lbs of torque, and 
horsepower calculated.

    An more accurate alternative might be to mount a disk brake rotor to 
the PSRU,  attach a brake to a long bar whose end rests on a scale, top 
end attached to a bracket on the engine or mount (use a strong 
attachment for that one!).  Scale readings would provide torque directly 
when length of bar is factored in.

Phil in Willowbrook, 20B in RV-10 (wings done, fuse ships this week, 
time to port and assemble the engine)

Lehanover@aol.com wrote on 1/22/2005, 1:10 PM:

 > In a message dated 1/22/2005 12:08:34 PM Central Standard Time,
 > dale.r@cox.net writes:
 >
 > <<  Thank you very much for the idea.  It isn't directly
 > applicable to my situation, because I don't have a car
 > to use as a "chassis" test bed.  However, it did give me an
 > idea - using a gang of disc brake assemblies, for creating
 > an engine dyno that might come in at under $1000.
 > (Actually, a direct coupling to the truck rear-end might
 > do the job - if the brakes are big enough and I can figure
 > a way to take the strain reading directly from the axel
 > housing.)
 >
 > Dale R.
 > COZY MkIV #1254
 >
 >
 > There is more than one way to skin a cat.
 >
 > Don't forget the math to take out the effect of the differential
 > ratio, lest you report some giant numbers.
 >
 > Lynn E. Hanover
 >