Definition
An aeronautical beacon is a visual ground-based navigation aid that displays flashes of white and/or colored light to indicate the location of an airport, a heliport, a landmark, a point on a Federal airway in mountainous terrain, or an obstruction.
Plain English
A flashing light on the ground that pilots can see from the air, used to mark something important — usually an airport, a heliport, a hazard, or a key point along a route.
Context Anchor
Pilots may see aeronautical beacons near airports, heliports, landmarks, route points, or hazards that need to be noticed from the air.
Derivation
From Old English 'beacen,' meaning a sign or signal. Beacons have been used for centuries as visible markers — fires on hills, lighthouses at sea — and the aviation version carries the same idea: a light placed where it needs to be seen from a distance.
Why Pilots Care
Beacons allow pilots to locate airports from a distance at night or in reduced visibility, supporting safe visual approaches and navigation.
Intuition Check
A beacon is not just any light, and in this context it is not a radio signal. Here it means a flashing visual light used to mark something important for aviation.
Example Sentence 1
On the night cross-country, the student spotted the airport's rotating aeronautical beacon flashing white and green from ten miles out.
Example Sentence 2
Aeronautical beacons are listed for each airport to assist with visual identification during VFR operations.