Some dinghies and yachts also have wind vanes to provide more information on where the breeze is coming from… which can be especially useful when running downwind so you know when you are running by the lee (ie. when you are sailing the boom is normally on the other side of the boat to where the wind is coming from. When sailing by the lee, you are sailing with the wind, but the wind has moved around and is just coming from the same side as the boom is on, which can cause you to jibe unexpectedly).
They are attached to the mast, generally located between the deck and boom, or at the top of the mast.
For most of us, we want to get the maximum speed out of our sailing, whether we are Laser sailing, sailing on any other type of dinghy, or on a yacht. And this means that we have to be able to trim the sail to get the most out of it. By having telltales on the sail, it gives us a good indication of how we have to trim the sail to be optimal.
Telltales are small strips (approx 10cm or 4in long and 5mm or 1/5in wide) of tape or material located on both sides of the sail. Sometimes there may be a few sets of telltales on the 1 sail. Light yarn telltales are preferred by many for their
If the telltale on the windward side is flapping or hanging straight down, the air is not flowing over that surface of the sail optimally, so you need to pull it on (you may also see an uneven surface in the front of the sail along the mast edge, or the luff).
Conversely, if the leeward telltale is flapping, the sail is pulled on too much and needs to be eased.