Video: Why NASAs Martian Helicopter CANT fly on Earth!
[This is a bit of a convoluted video, but it does actually explain an interesting scientific twist. Since the NASA helicopter will be the first device to try and FLY on another planet, it presents some unique problems. On the one hand, there is a lot less gravity on Mars, but on the other hand, the atmosphere is a lot thinner. The bottom line in this convoluted video, but the only one to touch on this problem, is that they had to remove most of the weight from the helicopter. They can recreate the extreme low pressure of the Martian atmosphere, but they can't reduce the power of gravity on Earth to simulate that of Mars. So it presents and interesting twist and problem. Jan]