This LZ-1A was built initially as a Sikorsky R-6 and TOC with the USAAF as 43-45480. The frame was selected for testing with the new Doman rotor-hub system. The blades are held on the hub similar to a variable-pitch airscrew blades and the rotor incorporates a gimbal mounting to provide the necessary tilting of the rotor disc. The flight tests were started in early 1950 with remarkably good results and so the larger LZ-2A Pelican followed. The LZ-1a is now on display at this super museum.

Ex USAAF Hoverfly II 43-45480 converted post-war by Doman Helicopters Inc for rotor blade development tests. The American Export Airlines flying boat in the background is the world's only surviving Sikorsky VS-44A, NC41881 "Excambian" (c/n 4402).