Geopotential altitude represents the height above a reference surface called the geopotential surface, which is a hypothetical surface where the gravitational acceleration is constant. Geopotential altitude helps in understanding the potential energy per unit mass of an aircraft in the Earth’s atmosphere. The formula to calculate geopotential altitude from geometric altitude is given by:
- : Geometric height or altitude in m.
- : Geopotential height in m.
- : Mean radius of the Earth in m.