International Code of Signals
These are a set of 39 flags, 26 letters, 10 numbers, 3 substitute flags and one answering pennant. They are used by ships at sea to indicate various conditions of the ship and the activities it is engaged in. Examples of this would be if a vessel had a diver down and was warning other nearby ships to stay clear.
- Answering Pennant: used to indicate that the signal has been received.
- Substitute Flags: these are used in a situation where the vessel needs to show more than one of the flags already used. For example if the ship wanted to display the flags A D E D, it could display them using A D E [second substitute], indicating to repeat the second flag there.
Letters A-M
| A | I have a diver down, keep well clear and at a slow speed. |
| B | I am taking on, carrying or discharging dangerous goods. |
| C | Yes, affirmative. |
| D | Keep clear of me, I am manoeuvring with difficulty. |
| E | I am directing my course to starboard. |
| F | I am disabled, communicate with me. |
| G | I require a pilot; I am hauling nets. |
| H | I have a pilot on board. |
| I | I am directing my course to port. |
| J | I am on fire and have dangerous cargo on board. Keep well clear. |
| K | I wish to communicate with you. |
| L | You should stop. I have something important to communicate. |
| M | My vessel is stopped and making no way through the water. |
Letters N-Z
| N | No, negative. |
| O | Man overboard. |
| P | The ship is about to leave port; Your lights are out or burning badly. |
| Q | My ship is healthy and I request free pratique. |
| R | No signal. |
| S | My engines are going full astern. |
| T | Keep clear, I am engaged in pair trawling. |
| U | You are standing into danger. |
| V | I require assistance. |
| W | I require medical assistance. |
| X | Stop carrying out your intentions and watch for my signals. |
| Y | I am dragging my anchor. |
| Z | I require a tug; I am shooting nets. |
Numbers 0-9
