Basics of sail trim

We must trim “change” the sails to reflect the boat’s angle to the wind (point of sail) and cater for changes in apparent wind velocity to control the “power”.

If the sails are not trimmed correctly they may “luff” or fail to work effectively.

If a boat is overpowered when upwind and reaching you may experience excessive heel and weather helm (having to fight the helm to keep the boat from rounding up into the wind). In light to moderate wind, you will want to trim effectively to make the most of what wind there is.

Upwind (also referred to as “close-hauled”, “beating” and “on-the-wind”)

  • Trying to sail as close to the wind as possible with-out sails flapping.
  • Mainsail and headsail should be trimmed in tight (guideline boom does not go over centre line, headsail just kissing side stay)

Reaching (Close reach, beam reach and broad reach)

  • Sailing across the wind
  • Mainsail will be approximately half-way out, as will headsail

Downwind (also referred to as running)

  • Sailing away from the wind
  • Mainsail and headsail will be eased nearly all the way out

Tell Tales (woollies)

Tell tales are the strips of ribbon or wool on either side of the sail which we use as an aide to ensure the sail is trimmed correctly.

  Ideal trim Sail too far out or sailing too close to the wind Sail in too tight or need to point closer to the wind
  Both tell tales flowing back in parallel Inside or windward tell tale not flowing, outside tell tail flowing back Outside or leeward tell tale not flowing, inside tell tail flowing back
  Equal wind flow over both sides of the sail No wind flowing over the windward side No wind flowing over the leeward side
Upwind (sails already in tight) Keep sailing fast Too close to the wind:  Come down – pull the tiller toward you Not sailing close enough to the wind – push the tiller away
Reaching Keep sailing fast Trim sail in Ease sail out

TIP:  If in doubt – let it out.  Then pull it in until the tell tales are flying nicely

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