Definition
A combined navigation receiver and indicator mode that displays course guidance from either a VOR station (for en route and terminal navigation) or a localizer (for the lateral course of an ILS approach). On an HSI or course deviation indicator, the same needle and course selector are used for both signal types, with the receiver automatically interpreting the tuned frequency and displaying deviation accordingly.
Plain English
It's the shared navigation mode that lets one needle in the cockpit show the airplane's position relative to either a VOR ground station or the runway centerline signal of an ILS, depending on which one is tuned.
Context Anchor
Seen on or near an HSI when selecting the navigation source for instrument flying, especially when tracking a VOR course or following a localizer toward a runway.
Derivation
VOR stands for VHF Omnidirectional Range, a ground station broadcasting course information in all directions on VHF frequencies. LOC stands for localizer, the part of an ILS that provides lateral guidance to the runway centerline. The combined label reflects that one receiver and one indicator handle both.
Why Pilots Care
Allows a single instrument to handle both VOR tracking and localizer approaches without needing separate displays or frequent switching.
Intuition Check
VOR/LOC does not mean the airplane is using VOR and localizer guidance at the same time. It means the equipment is set up to use one of those two ground-based navigation signals, depending on what is tuned and selected.
Example Sentence 1
After tuning the ILS frequency, the pilot confirmed the receiver had switched from VOR to VOR/LOC mode and the needle was tracking the localizer.
Example Sentence 2
With the navigation source set to VOR/LOC, the HSI needle centered as the aircraft flew directly toward the VOR station.