RADALT (Radar Altimetre) Antenleri

A radar altimeter (RA, RALT, RADALT) measures altitude above the terrain presently beneath an aircraft or spacecraft. This type of altimeter provides the distance between the antenna and the ground directly below it, in contrast to a barometric altimeter which provides the distance above a defined vertical datum, usually mean sea level. When used on aircraft, it may be known as low-range radio altimeter (LRRA).

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