Now that my posting issues have graciously been fixed by the mods (sincere thank you by the way). Per your request:
Sikorsky 350mph commercial project
Source:
Flying Review International, August 1968
Fresh out of the restoration shop at Ft. Rucker! Can put up more pictures if anyone is interested.
Fresh out of the restoration shop at Ft. Rucker! Can put up more pictures if anyone is interested.
Wish they'd have been that kind to their XCH-62 and their AH-56 Cheyenne.
"Death of a Titan"
On Oct. 11, 2005, the U.S. Army Aviation Museum in Ft. Rucker, Alabama destroyed the sole Boeing XCH-62 Heavy Lift Helicopter (HLH) prototype. A lack of adequate protection over the prior two decades resulted in premature structural corrosion and decay. Photo by Michael Merritt.gallery.vtol.org
Not a new idea by Sikorsky : This ABC UTTAS proposal was shown
in Air & Cosmos 12.1968 (No design/type numbers given) :
here is a weird picture to Sikosky S-69 helicopter model,from L + K 19/1972
I guess it makes sense in terms of smaller total rotor diameter and not losing any potential lifting power to the anti-torque rotor...Wow, never seen the ABC crane before. Thanks for post, hesham.
I know Kamov Ka-32s are used as flying cranes with underslung loads in the civilian construction sector, and I've read it's because they are more precise and stable than conventional helicopters. Same for the K-Max and it's intermeshing rotors.Not really. ABC and contra-rotating rotors have inherent asynchronous trimming behavior that would be exacerbated with an underslung load (think pendulum oscillations).
In effect, it's a very similar limitation than moveable Canards on airplanes.
An application today would do good using the extra available shaft power to drive E-Fans as anti-torque.
I suspect those guys are absolutely paranoid about not letting the loads swing around.I know Kamov Ka-32s are used as flying cranes with underslung loads in the civilian construction sector, and I've read it's because they are more precise and stable than conventional helicopters. Same for the K-Max and it's intermeshing rotors.