Tac tical ir avigation. A navigation system based of an aircraft's receipt of bearing and range information from ground stations. TACAN stations were referred to by their "Channel number" such as Ch 89 for NKP.
TACtical Aid to Navigation (military UHF navaid)
ultra-high frequency Tactical Air Navigational Aid
TACtical Aid to Navigation - a ground based military UHF navigation aid
Military format for azimuth and distance.
Tactical Air Navigation