To reiterate the reasons for the dual tripod motor mount
for recent listers:

A. No motor mount cross tube under the engine is required giving 
maximum room for an under the engine radiator in a stock cowl.

B. Vibration transmissions due to  inevitable torque fluctuations
is reduced due to wide spread rubber motor mounts. Rubber mounts run
cooler due to being further away from the engine.

C. More room along the exhaust side of a tractor engine'd airplane
 for turbo's or tangential, under the cowl, mufflers.

D. Simple to build and stress.

E. All prop reaction torque is taken by the 1/2 inch thick  redrive 
plate and motor mounts directly without first going through Tracy's 
spacers and ten mm bolts into the engine first. These spacers and 
bolts then only need to deal with engine torque which is roughly 
half of prop torque.

F. Simple to move the starter up along side the redrive to give 
more room for the rad under the engine.

Paul Lamar
 
The AirCraft Rotary Engine NewsLetter.              Powered by Linux.

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