Flight Level(FL)

Definition

A standard pressure altitude expressed in hundreds of feet with the altimeter set to 29.92 inHg. Flight levels are used above the transition altitude to ensure vertical separation between aircraft.

Related Terms

Pressure Altitude

The indicated altitude when the altimeter is set to 29.92 inHg (1013.25 hPa). Us...

Transition Altitude

The altitude at which pilots change from QNH altimeter setting to standard press...

Altimeter Setting(QNH)

The barometric pressure adjusted to sea level used to set the altimeter so it re...

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