JohnO wrote:

Hi,

Can someone point me to any official accident statistics that would
demonstrate the relative accident rates of various classes of certified
and experimental helos? Specifically I would want to exclude any
accidents that were pilot error or failure of maintenance. and only
consider accidents where there was a design fault

You can search the NTSB accident records by make
of aircraft. You'll have to read the summaries
yourself to exclude pilot error.

Actually, for the Rotorway with the turbine
conversion there may not be very many entries
since they haven't been available for that long,
and there are not that many flying.

Good luck,

Don W.