Plain English Meaning

A test the pilot does in the air to make sure the VOR navigation receiver is showing the correct bearing. The pilot flies over a known point or compares two receivers, then checks that the readings are within an allowed margin of error.

Full Definition

An in-flight procedure used to verify the accuracy of a VOR receiver by comparing the indicated bearing against a known, charted reference point while airborne. Permitted methods include flying over a designated VOR airborne checkpoint, flying over a prominent ground feature on a published radial at a specified altitude and distance, or, where no checkpoint is available, performing a dual VOR between two independent VOR receivers tuned to the same . The maximum is plus or minus 6 degrees for a designated airborne checkpoint, and 4 degrees between two receivers in a .