What term is used to describe a string or ribbon attached to a sailboat’s sail to indicate wind direction?

Wind is the key element which powers every sailboat. Boats are not often pushed by wind (unless it comes directly from behind); rather, wind blows across the sails to create lift, similar to airplane wings. On a sailboat, the curved sail functions in the same manner, creating lift to propel the craft forward.

Prior to leaving the dock, it is necessary for a sailor to check both the wind speed and direction. Knowledge about the movement of the wind in the sails is crucial for safety and making needed adjustments.

Once underway, there are a variety of ways for sailors to stay attuned to wind shifts. One way to do so is via changes in the water. White caps and darker patches both indicate wind change. White caps mean the wind is getting stronger, while a darker patch of water can indicate a gust or a shift in wind direction. Yet another method used is the “telltale” (or tell-tale) a piece of yarn, ribbon, or fabric attached to a sail or other rigging on a sailboat.

For a sail to work properly, air must flow down both sides. Telltales provide information about airflow by giving visual clues regarding wind direction. If the telltales are streaming straight back, everything is good; the wind is flowing smoothly over both sides of the sail. If the windward side (direction from which the wind is coming) telltale is fluttering, the sail needs to be pulled in. Fluttering telltales on the leeward side (the direction the wind is going) mean that the sail needs to be let out.