A flight level (FL) is a standard nominal altitude of an aircraft, in hundreds of feet. This altitude is calculated from the International standard pressure datum of 1013.25 hPa (29.92 inHg), the average sea-level pressure, and therefore is not necessarily the same as the aircraft's true altitude either above mean sea level or above ground level.
Read more about Flight Level: Background, Transition Altitude, Quadrantal Rule, Semicircular/Hemispheric Rule, Reduced Vertical Separation Minima, Metric Flight Levels, Flight Levels in Russian Federation
Famous quotes containing the words flight and/or level:
“What a cunning mixture of sentiment, pity, tenderness, irony surrounds adolescence, what knowing watchfulness! Young birds on their first flight are hardly so hovered around.”
—Georges Bernanos (1888–1948)
“Success four flights Thursday morning all against twenty one mile wind started from Level with engine power alone speed through air thirty one miles longest 57 second inform Press home Christmas.”
—Orville Wright (1871–1948)