The rate of climb (ROC) in flight mechanics is a measure of how quickly an aircraft is ascending vertically. It quantifies the vertical speed of the aircraft as it climbs through the air. The rate of climb is usually expressed in units such as feet per minute (ft/min) or meters per second (m/s).
- : This typically represents the climb speed (or rate of climb speed) during the climb phase, usually measured in feet per minute (ft/min) or meters per second (m/s).
- : The flight path angle, which is the angle between the aircraft’s flight path and the horizontal plane, usually measured in radians.