Answer:

altimeter

Answer	Crossword Clue
ALTIMETER	It tells you how high you are
ALTIMETER	It works by comparing air pressures
ALTIMETER	Cockpit gauge

ALTIMETER	Aircraft device
ALTIMETER	Skydiving device
ALTIMETER	Navigation aid
ALTIMETER	Mountain climber's gadget
ALTIMETER	It takes measurements on a plane
ALTIMETER	Parachutist's device
ALTIMETER	Airplane navigation instrument.
ALTIMETER	Airplane apparatus.

ALTIMETER	Height gauge
ALTIMETER	Instrument measuring elevation
ALTIMETER	Servopneumatic instrument
ALTIMETER	Change around tempo for instrument in a cabin (9)
ALTIMETER	Height-measuring device
ALTIMETER	Highness guide
ALTIMETER	Instrument that's taken up