Ground speed is the horizontal speed of an aircraft or other object relative to the Earth’s surface. It is the actual speed at which the object is moving over the ground. The ground speed is affected by both the true airspeed (the speed of the aircraft through the air) and the wind speed and direction. The formula for ground speed can be expressed as:
Where:
- : Ground speed, which is the horizontal speed of the aircraft relative to the Earth’s surface.
- : True airspeed, which is the speed of the aircraft through the air.
- : Flight path angle, which is the angle between the aircraft’s velocity vector and the horizontal axis.