Sikorsky Aircraft developing world's fastest helicopter

Sikorsky Aircraft may have just built the world's fastest helicopter. The X2 unofficially broke the helicopter speed record in August, and the company's engineers and test pilots are still striving for faster and faster speeds.

What makes this helicopter so fast is its unique rotors: Rather than having one set of rotor blades spinning over the aircraft's body, it has two, with one mounted atop the other. This innovative approach has allowed Sikorsky to reach unprecedented speeds and may well influence the design of the next generation of helicopters.