# Vertical rate of climb and its variation with change of flight velocity and altitude

Answer 1. The vertical rate of climb is the altitude which the helicopter gains per second. This rate depends on the excess power and the helicopter weight. The vertical rate of climb decreases with increase of the flight speed and latitude.

Answer 2. The vertical rate of climb is the altitude which the helicopter gains per unit time. The rate depends on the excess power and on the helicopter weight. The excess power increases as the flight velocity is increased from zero to the economical speed. Consequently, the vertical rate of climb will increase. The vertical rate of climb decreases with further increase of the velocity along the trajectory.

The vertical rate of climb increases with increase of flight altitude from zero to the engine critical altitude. The rate decreases at altitudes above the critical altitude.

Answer 3. The vertical rate of climb is the altitude which the helicopter gains per second. This rate will be the higher, the larger the excess power AN and the less the helicopter weight. The excess power decreases with increase of the flight speed; consequently, the vertical rate of climb also decreases.

The power available and the excess power decrease with increase of the flight altitude.

This means that the higher the altitude, the lower the vertical rate of climb. The altitude at which the vertical climbing velocity equals zero is called the helicopter dynamic ceiling.