Sikorsky HLH (?) drawings

[flateric]

Found at Worthpoint actually, erroneously referred as S-71

 

[JohnR]

What was the dates for the S-71?

 

[Apophenia]

What was the dates for the S-71?

The S-71 gunship was proposed in 1973.

Sikorsky S-71 Advanced Attack Helicopter (AAH) – Igor I Sikorsky Historical Archives

www.sikorskyarchives.com

The Heavy Lift Helicopter competition emerged in 1970 with Sikorsky submitting its unsuccessful S-73 concept in February 1971.

Sikorsky Heavy Lift Helicopter (HLH) – Igor I Sikorsky Historical Archives

www.sikorskyarchives.com