"Peter Dohm" wrote

The point here is that, although a loss of power is the most obvious
outcome
of a torsional resonance problem, it is not the only failure mode and may
not even be the worst. For example, the same "Contact!" article also
mentioned severe flexing of a bulkhead in the fusalage due to a resonance
between the complete engine and drive system and the fusalage at critical
speed(s). That caused me to be even more afraid than the driveshaft and
redrive problems.

That is along the lines of what I wrote. The more a person reads about
torsional resonance, the more one understands how much there is that can go
wrong.

I am convinced not to use a long driveshaft, for my personal use. g
--
Jim in NC