Answer: shoran

AnswerCrossword Clue
SHORANAircraft navigation setup
SHORANNavigation aid.
SHORANAir navigation system
SHORANAircraft navigation system
shoransystem for aircraft navigation in which two signals sent from an aircraft are received and answered by two fixed transponders, the round-trip times of the signals enabling the navigator to determine the aircraft's position
shorana type of navigational system