Flight Level

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:

    No Raven’s wing can stretch the flight so far
    As the torn bandrols of Napoleon’s war.
    Choose then your climate, fix your best abode,
    He’ll make you deserts and he’ll bring you blood.
    How could you fear a dearth? have not mankind,
    Tho slain by millions, millions left behind?
    Has not conscription still the power to weild
    Her annual faulchion o’er the human field?
    A faithful harvester!
    Joel Barlow (1754–1812)

    Architecture might be more sportive and varied if every man built his own house, but it would not be the art and science that we have made it; and while every woman prepares food for her own family, cooking can never rise beyond the level of the amateur’s work.
    Charlotte Perkins Gilman (1860–1935)