Definition
A point along the route or airway segment between two VOR navigation aids where the pilot should change frequency and navigate using the next VOR ahead instead of the one behind. It is normally located midway between the two stations, but may be placed elsewhere when terrain, signal reception, or route geometry require it. When a COP is published on a chart, pilots are expected to use it.
Plain English
The spot on an airway where you stop using the VOR you've been tracking from and switch to tracking the next VOR up ahead.
Context Anchor
Seen on instrument-route charts when flying between navigation stations or published route points.
Derivation
Plainly named: the point at which you change over from one navigation source to the next. Worth noting only because pilots sometimes assume they can switch whenever signal quality drops — the COP is a specific, charted location.
Why Pilots Care
Using the COP keeps navigation signals strong and course guidance accurate during the transition between aids.
Intuition Check
Do not read “changeover point” as just any place where something changes. In instrument flying, it is a specific published route point for switching navigation guidance.
Example Sentence 1
Approaching the changeover point, the pilot tuned the next VOR, identified it, and centered the needle on the outbound radial.
Example Sentence 2
At the COP the aircraft was exactly midway in signal strength between the two facilities.