Curious Question wrote in
:

Stan Gosnell wrote:

It isn't survivable, just as losing a wing on an airplane isn't
survivable, except in the most unusual of circumstances.

Stan..... Do you have any idea as to how often a blade has been
thrown since the invention of the helicopter, gyro, etc.

How about in the last decade.

It's pretty seldom, I suspect about the same frequency as airplanes losing
wings. The only one I've heard of recently is a Sikorsky S76 which lost a
blade (actually the blade broke off relatively close to the head) over the
North Sea last year. All aboard were lost. The blade had been previously
hit by lightning, and this coupled with a manufacturing defect caused it to
fail. Losing a main rotor blade on a certificated helicopter is very rare,
unless it's in conjunction with a collision, where the blades hit something
and subsequently fail. I fly them for a living, and losing a MR blade is
something I just don't worry about.

The NTSB, and perhaps other national aviation safety agencies, publishes
summaries of all aviation accidents in the US, going back to 1962, and it's
searchable. You should be able to find what you're looking for there, at
least for the USA. http://www.ntsb.gov/aviation/aviation.htm

--
Regards,

Stan