There is still the PSRU requirement due to the  engine still
 running at 6000 RPM where Tracy's box looks like overkill and timing belts
 at
 125 HP start getting bulky  and at 3 to 1 the large sheeve is also pretty
 large. Might be that a rotrax 914 gearbox  could be adapted to Jeff's psru
 plate and spacers.

 george grimes

 The torque pulse amplitude is the same for one rotor or two rotor.

 To scale the gear box down is a technical risk.

 Paul Lamar

Paul, very good observation. Makes me wonder if a four rotor firing at 90
degree intervals might be able to use Tracy's gearbox after running FEA on
the thrust bearings.

george grimes

Probably. The gear set is normally used with a 650 ft pound Ford Power Stroke Diesel pick up truck engine and diesels are known for their sharp torque pulses.


BTW In fact the Renault aircraft diesel would destroy constant speed props in a heart beat.

That is probably why the Continental two stroke aircraft diesel engine never made it out of the prototype stage. I don't know how the Junkers Jumo ever lasted in 1935 or the Packard diesel before that. The props had to be cannon proof.

Hope springs eternal :)

Paul Lamar