Definition
A ground-based radio navigation system that transmits a signal in all directions, allowing a properly equipped aircraft to determine its bearing to or from the station along any of 360 selectable courses (radials). The system operates in the very high frequency (VHF) band between 108.0 and 117.95 MHz and provides the basis for much of the airway and instrument approach structure in the United States.
Plain English
A radio beacon on the ground that lets a pilot know which direction the aircraft is from the station, so it can be used to fly along a chosen line in or out of that station.
Context Anchor
Seen during instrument flight planning, en route navigation, holding, approaches, and missed approach instructions that use a VOR as the navigation reference.
Derivation
VHF stands for very high frequency, the radio band the system uses. Omnidirectional comes from Latin omni (all) and directional, meaning the station sends signals in every direction. Range here means a navigation aid you can fly to or from along a measured course, not how far away you can use it.
Why Pilots Care
Provides reliable course guidance independent of visual references, forming the backbone of many IFR airways and approaches.
Analogy
A VOR station is like a hub with many straight direction lines coming out of it. The aircraft receiver helps the pilot choose one of those lines and stay on it.
Intuition Check
Do not read “range” here as distance. In “VOR,” range means a radio navigation aid that provides direction information from a ground station.
Example Sentence 1
After departure, the pilot tuned the VOR system to the next station on the airway and centered the needle to track inbound on the assigned radial.
Example Sentence 2
When the VOR system signal flagged, the crew cross-checked with GPS to confirm their position.