The Official Website Sail Shapes
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Sail Shapes

One of the most discussed topics among all sailors is SAIL SHAPES.

Most of our Hartley Members have been made very aware of the importance of the "TELL TALES" at our early session clinics, but I know, by looking at the Boats sailing round before races that many skippers still don’t know how the TELL TALES work or what to do to the sail controls to make them work.

One thing to remember is that the foot tension controls the bottom 1/3 of the sail, the spreaders/diamonds control the middle and the luff tension determines the sail shape from the middle to the head.

Just for the exercise, before going out for your next sail pull the luff (cuningham) control down as tight as possible and watch the sail change shape at the head. Then pull the vang on hard and watch the leech of the sail hook, you will be amazed.

 

THE FOLLOWING INFORMATION IS FROM HOOD SAILS.

TELLTALES, placed correctly on sails, are a simple and highly effective means of getting basic trim information, to ensure good sailing performance. Telltales need to be placed in the sails draft and along its trailing edge.

Here are some guide lines ~~

 

HEADSAIL

Use three telltales on the headsail for trim control and accurate sheeting angles. They should be placed about l5cm. aft of the luff,20%,40% and 60% up the full length of the sail (see diagram A).

A further two telltales placed 30cm in from the leech and parallel to the lowest and highest of the luff telltales will give further trim information

Beating and reaching

-sheet leads are correct when the top and bottom tell­tales on the 111ff flutter and fly straight at the same time.

-trim and heading are correct when the telltales on the opposite side of the sail fly straight aft.

-if the heading is too low, or the trim too tight, the leeward telltales flutter.

-if the heading is too high, or the trim too loose the windward telltales flutter.

-if the sail shape is too full(sheet leads too far for­ward) for the apparent wind the forward windward and the aft leeward telltales flutter at the same time.

MAINSAIL

The most important trim indicator is that placed on the trailing edge of the top batten. Further telltales can be placed on the second batten and vertically along the draft(see diagram B).

Beating and reaching.

  • -trim and heading are correct when the telltale on the top batten flies straight aft.
  • -if sheet trim is too tight or the traveller is too far to weather, the telltale on the top batten flies to leeward.
  • -if the heading is too low, or the trim too tight, the leeward telltales flutter.
  • -if the heading is too high, or the trim too loose the windward telltales flutter.
  • -if the sail shape is too full(sheet leads too far for­ward) for the apparent wind the forward windward and the aft leeward telltales flutter at the same time.

MAINSAIL

The most important trim indicator is that placed on the trailing edge of the top batten. Further telltales can be placed on the second batten and vertically along the draft(see diagram B).

Beating and reaching.

  • -trim and heading are correct when the telltale on the top batten flies straight aft.
  • -if sheet trim is too tight or the traveller is too far to weather, the telltale on the top batten flies to leeward.