Thule

A VORTAC is a combined facility that houses a civil VOR and a military TACAN at the same site. It serves everyone from one location: civil aircraft read bearing from the VOR and distance from the TACAN's DME component, while military aircraft use the complete TACAN for both bearing and distance. To a civilian pilot, a VORTAC behaves exactly like a VOR-DME — you tune the VOR frequency and automatically receive paired DME distance.

VORTACs are extremely common, particularly across the United States, and form a backbone of the airway system. Because they deliver both radial and distance, they provide a full rho-theta position fix from a single tuning, support DME arcs and approach procedures, and remain part of the resilient navigation network being retained as a backup to GPS.