Flags on ships (and boats) communicate. They are intended to send messages to other boats (and ships), and they are structured to do so internationally. Each flag by itself and many combinations provide very specific information, which you should know before you raise any flags.
If you are a serious boater, you will have a complete set of nautical flags available for use. The flags represent the letters A-Z, the digits 0-9 and four special flags. The special flags indicate that you’re answering a signal or are repeating a specific letter.
Also, if you’re a member of the United States Power Squadrons, you may have flags for them. Their flags indicate membership and rank. You may also have your state’s flag, and you should certainly have the U.S. flag.
Each of the letters, when flown alone, carries a specific meaning. The flag for “B”—a solid red—means you’re carrying a dangerous cargo. “I”—a black circle on yellow—means you’re altering course to port. “Z,” composed of four triangles (yellow, blue, red and black, starting clockwise from the top) means you require a tug.
Thus, you should be careful when raising sailing flags, so that you raise a flag which matches your intention or situation. If your boat is named Zorro, don’t raise the “Z” flag alone, or you may suddenly be popular.
One signal to know and not use unless you’re serious is the distress signal. This signal is composed of the “N” and “C” flags, with the “N” on top. The “N” carries a blue-and-white check pattern, while the “C” flag has blue stripes top and bottom, a red one across the center and two white stripes between each blue and the red stripes. Never signal distress unless you mean it.
Other combinations of flags also carry meaning. “C” over “N,” the reverse of distress, means “I am unable to give assistance.” “A” over “E” means that you must abandon your vessel; “A” is white to the left and blue to the right, with a triangle cut out. “E” is blue over red. I hope you never need that signal.
The American Flag
When using American flags for boats, you should follow all the recommended nautical flag etiquette rules. It should be flown from 0800 until sunset or when entering/leaving port. For most power boats, the flag will fly from the stern. Sailboats will raise it on the gaff, the leech of the aftermost sail or the backstay. When at anchor, all U.S. ensigns should be flown from the stern.
In domestic waters, the yacht ensign is frequently flown instead of the national ensign. It should never be used internationally, as it has no meaning.
Many nautical organizations have their own flags. The United States Power Squadrons has a flag, as do its districts. The U.S.P.S ensign may be flown instead of the national ensign.
Yacht clubs have their own burgees, while a boat’s owner may have a private signal. The cool thing about a private signal is you get to design it yourself. The disadvantage, of course, is that it will be more expensive since it’s custom made. Your private signal should be unique to you, not to include the ensign of another country, or it could be in bad taste.
Most small boats, as a practical matter, will probably only fly the national ensign and possibly the club burgee. Most sets of signal flags have flags too big to be used effectively on small personal watercrafts, especially for that display of flags called “dressing ship,” when they’re all flown from bow to stern. If you have a larger vessel, however, you’ll be able to get a set of signal flags to fit its size.
Many specialty flags for boats are available. For example, fishing enthusiasts may fly the flag of their favorite fish. Others may indicate “sober boating.” One of the more well-known examples is the “Cocktail Flag,” which I highly recommend never be flown while under way.
The private signal, discussed previously, is obviously a specialty flag. If you want to fly one, be creative in your design.
One comical set which can be flown on International “Talk-like-a-pirate” is the letter “R” followed by the 1st substitute (indicating that the message repeats the first letter, or “R”), the 2nd substitute (showing that the message repeats the second letter, or “R”) and the 3rd substitute (meaning the messages repeats the 3rd letter, or “R”). The message, therefore, is “RRRR.”
Finally, note that there’s a difference between boats and ships. The short version of the difference is that ships can carry boats, but boats can’t carry ships. Whichever you own, however, you should raise your flags seriously.