An apparatus for measuring altitude.

plural of altimeter

(aviation) A type of altimeter which measures vertical distance to the surface below, using radio, radar, sonic, laser, or capacitive technology.

plural of absolute altimeter

An altimeter that uses a narrow radio or radar beam directed at the ground

(aviation) A device which measures the altitude by performing measurement of the ambient pressure and comparing it against a reference pressure at a known altitude, to give a pressure altitude.

plural of pressure altimeter

plural of radio altimeter