In article , Stephen D. Poe
writes
Anytime you develop a totally new type of aircraft and have to also
develop new operational concepts you get fatal accidents. Go back and
review the early days of everything from the Harrier to the early jets
and helicopters.

The Harrier didn't do too badly in US service at the start, they had a
period of nearly two years accident free.

Also note the operational requirements are inherently more dangerous
than, say, circumstances where you rarely, if ever, fly below several
thousand feet.

The Harrier regularly operates in an environment unique to itself,
basically zero air speed very close to the ground. If anything happens
it's game over, all the pilot can do is pull the handle. No other
aircraft is intentionally put in the same situation (choppers can auto-
rotate if needed). STOVL JSF has a more complicated system with more
failure points.

It's not that the Osprey is more dangerous or has resulted in more
fatalities than many of the older planes, it that we've become less
tolerant of failures during R&D T&E.

The problem with the Osprey is the inability to demonstrate the problems
have been fixed. It's a very complex creature and Bell/Boeing are
determined to try to fix it (tilt-rotor being their pet technology)
rather than look at other alternatives which may have fewer built in
problems.

--
John