A closer look
If you've ever wondered why we don't have supersonic helicopters zipping around, blame physics. A helicopter flies by spinning blades through the air. But as the chopper moves forward, the advancing blade moves at the speed of the rotation plus the speed of the aircraft. If a helicopter flies too fast, the tips of the blades hit the speed of sound, creating massive shockwaves, catastrophic vibration, and immediate self-destruction. The vehicle is literally holding itself back.






