I have been following the various PSRU discussions with interest, and it is clear that torsion vibration is the big problem.
Has anyone tried using a quill shaft (torsionally "soft") to decouple flywheel speed fluctuations from the prop?
If you drive from the flywheel at the rear of the engine, and run a shaft through the vee to a front thrust bearing, by my back-of-the-envelope calculations you could allow several degrees of twist in the shaft without over stressing it.You would also get a usefully high thrust line, exhaust manifolds the right way around, and possibly better access to accessories.
Since this is not the standard way of doing things, what have I missed / got wrong?
Has anyone tried using a quill shaft (torsionally "soft") to decouple flywheel speed fluctuations from the prop?
If you drive from the flywheel at the rear of the engine, and run a shaft through the vee to a front thrust bearing, by my back-of-the-envelope calculations you could allow several degrees of twist in the shaft without over stressing it.You would also get a usefully high thrust line, exhaust manifolds the right way around, and possibly better access to accessories.
Since this is not the standard way of doing things, what have I missed / got wrong?