In UK aviation radiotelephony usage, the vertical distance of a level, a point or an object considered as a point, measured from mean sea level ; this is referred to over the radio as altitude.

In UK aviation radiotelephony usage, the vertical distance of a level, a point or an object considered as a point, measured from a specified datum ; this is referred to over the radio as height, where the specified datum is the airfield elevation ( see QFE )

0.003 seconds.