Was reading up on the Heavy Lift history for the US Army, and tripped over a few stories about the XCH-62 (Boeing Vertol).
(It looks like a Sikorsky S-64 Skycrane had a baby with a Chinook, and it was huge).
The Sikorsky proposed offering for the Heavy Lift project was the S-73, which lost out to the XCH-62 - which itself was canceled in 1975.
Are any of the test pilots who worked on that project still alive?
The U.S. Army's XCH-62 HLH aft rotor transmission was finally successfully tested at full design torque and speed, but the US Congress cut funding for the program in August 1975
I am not sure if "the design torque and speed" means rotor speed/transmission speed, or actually airborne and flying. The article on Wikipedia suggests to me that the whole thing never go airborne.
My first run through of some
archival info at DTIC doesn't reflect a flight test.
In 1983, NASA and DARPA ( Defence Advanced Research Projects Agency) plans were initiated to resume a Heavy Lift Research Vehicle [HLRV] test program, with a possible first flight in 1985, but was cancelled again.
(I have an inkling that the funding cut was associated with the general defense draw down related to the end of the Viet Nam war.)
Part of what intrigues me about that project is that i
t was going to be fly by wire in the 1970's.
EDIT:
(I finally got my answer: it never did fly.
See the bottom paragraph of this page).