Eurocopter, world's faster helicopter.

Aha, the information about the Cheyenne’s stability problems was something I didn’t know about. Mind you even if it flies like a sidewinder it’s still faster. The matter of stability is something that may not have been surmountable which is probably the reason they never progressed further. I also didn’t know the Comanchew was cancelled either. I guess I’m going to have to start taking an initerest in modern military aviation again.

The Lockheed Cheyenne had stability problems above 320 km/h and was cancelled in 1972. Subsequent to that, the Boeing/Sikorsky AH-56 Comanche was cancelled in 2004.

And if I’m not mistaken that speed still falls short of the American one from years ago the name of which escapes me at the moment (possibly Cheyenne?) which I seem to recall clocking 350 mph or so.

It’s been around for quite awhile, I’ve been following its progress in Aviation Week.
That’s a good speed for a compound helicopter, though I believe the Lynx (albeit a specially prepared one) still holds the regular (no props) helicopter speed record.

Compound helicopters have been around for a long time…witness the Rotodyne and the even earlier McDonnell XV-1…a piston powered compound that hit 200 mph in 1956. (Nothing against Eurocopter, but taking 57 years to gain an extra 100 over that ancient technology machine doesn’t seem that big of deal).
I wonder why no one has ever produced one?
There must be some drawbacks to the configuration despite their speed advantage.

Reminds me of the Rotodyne.