Definition
A military short-range radio navigation system that provides an aircraft with both bearing and slant-range distance to a selected ground station. Tacan operates in the UHF band and combines azimuth and distance information into a single facility, giving the pilot a continuous readout of direction to the station and miles from it.
Plain English
A military ground station that tells a pilot two things at once: which direction the station is from the aircraft, and how far away it is.
Context Anchor
Seen on military navigation equipment, approach charts, and charts that show Tacan or combined civil-military navigation stations.
Derivation
Tacan is short for Tactical Air Navigation. The word tactical points to its military origin: it was developed in the 1950s for fleet and battlefield use, where a single compact station could give pilots both direction and distance without needing separate equipment.
Why Pilots Care
Provides reliable navigation data when civilian aids are unavailable or insufficient for tactical needs.
Intuition Check
Do not assume Tacan is just another name for any navigation station. In aviation, Tacan specifically means the tactical air navigation system that gives both direction and distance information.
Example Sentence 1
The pilot tuned the Tacan station and read the bearing and distance directly off the cockpit display.
Example Sentence 2
During the low-level route, the crew used TACAN distance to confirm their position relative to the airfield.