Definition
Radials are the 360 magnetic courses that extend outward from a VOR ground station, each identified by its magnetic bearing from the station. A VOR transmits these as distinct signals, allowing an aircraft to determine which radial it is on relative to that station. Radials are always defined as the bearing FROM the station, regardless of the direction the aircraft is flying.
Plain English
Imagine 360 invisible lines stretching outward from a VOR station like spokes on a wheel, one for every degree of the compass. Each line is called a radial and is named by its compass direction from the station. The 090 radial points east from the station, the 270 radial points west, and so on.
Context Anchor
Seen in VOR navigation, instrument procedures, navigation charts, and air traffic control instructions that describe where an aircraft is in relation to a VOR station.
Derivation
From the Latin radius, meaning the spoke of a wheel or a ray. The image fits exactly: radials radiate outward from the VOR station like spokes from the hub of a wheel.
Why Pilots Care
Radials give pilots a precise way to determine their location relative to a VOR and to fly accurate inbound or outbound tracks.
Analogy
Think of a VOR station as the center of a bicycle wheel. The radials are the spokes, and each spoke has a number based on the direction it points away from the center.
Intuition Check
Do not assume a radial is named for the direction the airplane is flying. A radial is named for the direction the line extends from the VOR station.
Example Sentence 1
Cleared direct to the VOR, the pilot intercepted the 270 radial and tracked it inbound to the station.
Example Sentence 2
ATC cleared the aircraft to intercept the 180 radial and fly inbound to the station.