TACAN PRINCIPLES OF OPERATION

Navigation systems have evolved significantly since the Viking era, with Tactical Air Navigation TACAN) now widely used for air and sea travel. Post-World War Il, reliable systems became essential for safety and efficiency, as highlighted by DR. SUJAN KUMAR SARASWATI, in this article on TACAN’s operational principles.

Globally, Non-Directional Beacons (NDB), Very HighFrequency Omnirange (VOR/DVOR)) and Distance Measuring Equipment (DME) systems have been adopted by the international civil aviation community for providing ranging and azimuth information to the aircraft. Some countries (like the USA) have accepted the Tactical Air Navigation System (TACAN) as azimuth and distance navigation aids, though this system has not been accepted as a standard ICAO navigation system.

Tactical Air Navigation (TACAN) system evolved from Radio Transponder navigation system that was developed from the concept used for British Oboe system used during World War II. Post war, many companies in USA got involved in the development of TACAN for military aircraft. Hoffman Laboratories (Hoffman Electronics Corp. Military Products Division) led the project starting in late 1950s.

A Tactical Air Navigation (TACAN) system is essentially a defence system which can be installed on the ground, on buildings or on ships. It provides to the using aircraft, its positional information (azimuth and distance) with respect to the ground-based beacon. Positional information is provided in terms of its Rho (p) Theta (0) in the Polar Coordinate system, where Rho (p) is the distance in nautical miles (or Km) from the beacon and Theta (0) is the bearing angle w.r.t Magnetic North. Figuratively, the positional information, with reference to the ground-based beacon, can be represented as in Fig 1.

Information provided by TACAN is the same as the information provided by VOR(DVOR)/DME in Civil Aviation, however TACAN has many advantages over conventional DVOR/DME systems. Some of the advantages are described below:

TACAN Advantages: