Numeral Pennant

A triangular flag used in maritime signalling to represent numerical digits, typically in conjunction with other signal flags.

A numeral pennant is a key component of the International Code of Signals, a system used by ships to communicate essential information when visual signalling is required. These pennants are triangular in shape and are numbered from 0 to 9, each with a distinct colour pattern to ensure they are easily distinguishable from one another. They are often hoisted on a ship’s signal halyards in combination with alphabetical signal flags to convey specific messages, such as navigational warnings, distress signals, or routine operational instructions. 

The use of numeral pennants is particularly important in situations where radio communication may not be possible or practical, such as in areas of radio silence or when communicating with vessels that do not share a common language. For example, a ship might use numeral pennants to indicate a specific course, speed, or distance. In regattas or other maritime competitions, numeral pennants are also employed to identify race numbers or starting sequences. 

Their triangular design differentiates them from the square or rectangular alphabetical flags, and their standardised patterns ensure clarity and uniformity across international waters. Proper use of numeral pennants requires knowledge of flag etiquette and the ability to read and interpret the International Code of Signals, making them an indispensable tool for professional mariners and recreational sailors alike.