Definitions and Mnemonics for Sailors

(Taken from a web site by Geoff Kuenning)

Running Lights

port wine is red, so the red running light is on the left side of the boat.

Mast Lights

Red over Red
Captain's dead

Two red lights in a vertical line indicate a vessel "not under command."

Red over Green
Sailing machine

This is the less-used of the two sailboat lighting combinations. 

Red over White
Fishing tonight

If the fishing gear extends over 150 meters (492 feet) from the boat, an all-around white light must indicate the direction.

Green over White
Trawling tonight

Note that this is different from the general fishing lights.

White over White
Short tug/tow in sight

A short tow is under 200 meters (656 feet).

White over White over White
Long tug/tow in sight

A long tow is over 200 meters (656 feet).

Red over Red over Red
Rudder Rubbing Rocks

This refers to a vessel constrained by her draft. It applies only under the international rules.

White over Red
Pilot ahead

A pilot boat, waiting for "customers," displays this combination so that boats needing a pilot will be able to find it. Pilot boats also display this combination when waiting to pick up a pilot who is finished with a customer.

Red over White over Red
Red When Restricted

A vessel showing this combination is restricted in its ability to maneuver. Stay away! Examples include vessels servicing navigation marks, cables, pipelines; vessels dredging, surveying, or carrying out under water operations (such as dive boats); any vessel engaged in servicing, replenishing, or transferring cargo or persons; or any vessel launching or recovering aircraft.


Stern Lights

Boats can also show stern lights to help identify them. These are only visible when you are behind the boat. Some stern light combinations include:

Yellow over Yellow
A pushy inland fellow

This refers to the stern lights of a tug pushing a barge, under the inland rules only.

Yellow over White
My towline is tight

This refers to the stern lights of a tug towing astern.

Sound Signals

In sound signals, a short blast has a duration of about 1 second; a prolonged blast is 4-6 seconds.

Port Rudder Action
Blast twice short,
Turn to port
Leaving a Boat on Your Starboard Side
Double blast,
Starboard pass

A double blast always means that you are turning (COLREGS) or will turn (inland waters) to port. This means that you will pass the other boat on your starboard side.

Backing Down
Three in turn,
Power astern

This indicates a boat that is slowing or stopping to avoid risk of collision.

Danger Signal
Blast quick five
To stay alive

This is the danger signal, to be given if you think there is confusion or imminent danger of a collision.

Chart Scale

Small scale, small detail; large scale, large detail. So a large-scale chart is the one you'd ask for if you needed to enter a harbor.