As you probably know, the intention was to test whether or not the peroxide tip-driven rocket powered rotors would work as advertised. The main engine research was going slowly, so this was the first item to be tested, and we incorporated it into the engineering mockup which was intended as both a test bed and, of course, a marketing tool.

Had this test series been completed, flight tests to several thousand feet would have followed. Then, of course, main engine tests would have taken place eventually. In this context, the first flights--and as it turned out, the last--would have looked a little less silly.

The rotor head and rotors were pulled almost unchanged from an old Sikorsky S-58. The transmission and other stuff were removed, and the assembly modified with the tip thrusters.