A flywheel is a sledge hammer approach (to managing >torsional vibration

problems). IMHO it is better to >put a spring in there

and maybe some damping although that implies some >energy loss.
The rotor and counter weights alone have considerably >angular momentum.

Paul, the following page has an excellent article on torsional resonance.
http://www.primemover.org/Engines/Torsional/contact1/contact1.html

You can't fix a torsional vibration problem with springs if it's got a
resonance component. Might even make it worse.

Regards,
  Peter Militch

No but you can tune it to be out of range. Some damping also helps
but there is an energy loss. So far Tracy's solution with rubber
bushings is working fine. Some Ross boxes also work with just springs.
Some don't. Chuck Dunlap is not having problems as far as I saw at
the last Copper State with his Ross box. I flew in his airplane and
never ever noticed a resonant problem. Chuck is it still working?

Paul Lamar

Chuck wrote:

Yes it is still working fine. I disassembled the redrive last week when I
was installing my new engine. I saw no noticeable wear on the gears.(77
hours total time). I disassembled the engine and saw no abnormal wear on the
thrust bearings or races. My redrive has the clutch spring disk for
torsional damping.

Chuck Dunlap

 
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