Definition
A military ultra-high frequency (UHF) navigation system that provides an aircraft with both bearing (direction) and slant-range distance to a selected ground station. TACAN ground stations are often co-located with civilian VOR stations to form a VORTAC, allowing civil aircraft to use the distance (DME) portion while military aircraft use the full bearing-and-distance signal.
Plain English
TACAN is a navigation aid used mainly by the military. It tells a pilot two things from one ground station: which direction the station is from the aircraft, and how far away it is.
Context Anchor
You may see TACAN on aeronautical charts, in military flying information, or near facilities where a military navigation station is part of the navigation picture.
Derivation
From 'tactical,' meaning related to military operations, plus 'air navigation.' The name reflects its origin as a system designed for military aircraft needing accurate position information in operational settings.
Why Pilots Care
Gives precise navigation data in areas where civilian VOR/DME coverage is unavailable or during tactical operations.
Intuition Check
TACAN is not a route, clearance, or procedure. It is a navigation system that sends information an aircraft can use for direction and distance.
Example Sentence 1
The instructor pointed out that the navigation aid on the chart was a VORTAC, meaning it combined a civilian VOR with a military TACAN.
Example Sentence 2
Military aircraft often rely on TACAN for accurate positioning when operating over remote areas.