Anatomy of a Boat: Terminology

More Navigation Aids: ATON

Informational

i.e. fuel dock. Text on these aids is black. Will appear inside or around the shape.

Restricted Operation

i.e. Speed limit or no wake.

Danger

Displays nature of hazard.

Exclusions

i.e. swimmers only

Preferred Channel Green on top means preferred channel is to port if heading to open water. Red is secondary. Preferred Channel Red on top means preferred channel is to starboard if returning from open water. Green is secondary.

Nautical Charts and Navigation Aids

Diamond shape indicates the color of the buoy. An open circle at the base means there is no light on the buoy. In this example, the red circle means this red buoy also displays a red light.

This buoy is multi-colored, red over green. It has a red light on it.

Cracking the Code!

What do those numbers and letters mean?

Lighted beacon or lighthouse. Other information regarding a lighthouse may appear on the chart with the symbol.

FL G 4S This information, found along with a beacon symbol on nautical charts, tells you a lot. In our example at left, the beacon has a flashing (FL) light. It flashes every 4 seconds (4S). The light is green (G). At right, we have a beacon that gives 2 longer flashes followed by 1 short one (2+1). The pattern repeats every 8 seconds. The light is red.