What keeps the helicopter in the sky

Instead of wings helicopter is equipped with at least one rotor, the rotor blades which rotate at high speed, creating a lift force pushing up the helicopter. With increasing speed, this lift is reduced, so vortolety fly at a speed of a 130 to 350 km / h, that is smaller than that of most airplanes.
In addition to the lift rotor with a small slope creates a craving for translational motion.

Why helicopters are ideal for rescue?

Helicopters are the most maneuverable of the aircraft. Under the direction of an experienced helicopter pilot can fly very slowly, it is easy to change direction and even hover in one spot at the correct height, allowing you to get on board and distress survivors. In addition, the helicopter can land literally on the heels, picking up to the most inaccessible areas in the disaster area.