A helicopter's spinning rotor blades act as powerful wings. As they whirl around, air flowing over them produces an upward force, called lift. By altering the speed and angle of the rotor blades, the pilot can make the helicopter rise, fall, or hover. Helicopters are also able to fly forward and backward.
|This McDonnell Douglas helicopter has a T-shaped tail, which acts as a stabiliser, and long skids for landing.|