Definition
A service in which an air traffic controller uses radar to watch an aircraft's position during a published instrument approach (such as an ILS, VOR, or RNAV approach) to ensure the aircraft remains within safe lateral and vertical limits of the approach course. The controller does not fly the approach for the pilot; the pilot continues to navigate using onboard instruments while the controller provides advisories if the aircraft drifts off course or descends below a safe altitude.
Plain English
The pilot flies the approach using their own cockpit instruments, while a controller on the ground watches them on radar as a backup. If the aircraft strays from where it should be, the controller speaks up.
Context Anchor
Seen in instrument approach operations where radar coverage and controller services are available, especially during approaches flown in low visibility or cloud.
Derivation
Radar comes from “radio detection and ranging,” meaning using radio signals to find where something is and how far away it is. Monitoring means watching for a problem. Together, the term means ATC is using radar to watch the progress of an instrument approach.
Why Pilots Care
Provides an extra layer of safety and precision when flying approaches in low visibility or at busy airports.
Grounding Statement
Picture flying an approach in cloud while a controller watches your radar target and calls if you drift too far from where you should be.
Intuition Check
Radar monitoring does not mean ATC is controlling every part of the approach or guaranteeing safety. It means ATC is watching your radar position and may issue warnings or advisories when able.
Example Sentence 1
The controller advised, 'Radar monitoring of the ILS approach is in effect; report any difficulties on this frequency.'
Example Sentence 2
Radar monitoring of instrument approaches allowed the pilot to receive timely heading corrections during the low-visibility arrival.