VOR Navigation Explained
How VHF Omnidirectional Range stations work and how to track a radial to or from one.
A VOR (VHF Omnidirectional Range) lets an aircraft determine its bearing to or from a ground station along any of 360 radials — magnetic courses radiating outward from the station like spokes of a wheel.
How it works
The station transmits two signals; the phase difference between them encodes the radial. Your receiver compares them and shows where you are relative to a course you select with the omni-bearing selector (OBS). Because it relies on line-of-sight VHF signals, a VOR’s usable range depends on altitude and terrain.
Reading the indicator
Set a course in the OBS. The course deviation indicator needle shows whether that course is to your left or right, and a TO/FROM flag tells you whether flying the course takes you toward or away from the station. Crucially, the VOR indication is independent of aircraft heading — the needle shows your position relative to the selected radial, not where the nose points.
Tracking a radial
1. Tune and identify the station by its Morse code ident — never navigate on an unverified station. 2. Centre the needle with a TO indication and note the course; that is your bearing to the station. 3. Fly that heading, correcting for wind by turning slightly into it until the needle stays centred — this is your wind correction angle. 4. Bracket the wind: if the needle drifts, turn toward it, re-centre, and take out half your previous correction.
Passing over the station the TO/FROM flag flips and the needle becomes briefly erratic — the *cone of confusion*. VORs remain a backbone of the airway system even as RNAV/GPS navigation grows.
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*Reference and training only — not for navigation. Always consult the current AIM, your aircraft’s POH/AFM and a certificated flight instructor.*