The Big Deuce

[Gunkorsky]

When first publicly unveiled in January 1954, the Sikorsky S-56 was introduced by its manufacturer as a "giant, twin-engine transport", that represents a "tremendous advance in the art of designing and building helicopters".

 

In fact, the S-56 was the biggest, fastest and most powerful production helicopter in the free world until the introduction of Boeing Vertol's turbine-driven Chinook in 1961.

 

I’d appreciate any information on this terrific helicopter!

[Lu Zuckerman]

The US Army did not have their logistics and training program in place when they first received the S-56 (H-37).  The people training the army mechanics did not have a clue.  Here is an example.  During a training session covering the rotor system a student asked an instructor what would happen if the helicopter lost a blade in flight.  The instructor said that the rotorhead being fully articulated the remaining blades would reposition themselves keeping the rotor system in balance.  Technical note: The individual blades are balanced to ¼ inch ounce and the centrifugal loading was around 72,000 pounds.  If Nick Lappos is reading this use the term centripetal in place of centrifugal.