How to Maximize Lift
(and minimize drag)
• Lift and drag is variable
• Sails may be adjusted:
– Light Air
• Deep Draft, Draft Aft, more sail area
• Fuller shapes work because light air produces less
drag.
– Medium Air
• Reduce Draft, Draft Forward, maintain sail area
• Flatter shapes provide lift without excessive drag
– Heavy Air
• Reduce sail
– High wind velocities produce sufficient lift with much less
sail area.
– Overpowered is not fast
– Smaller flatter genoa/jib
– Reefed mainsail, full out haul to flatten the mainsail
General Sailtrim/Boatspeed
Guidelines
• Light Air,
– Sail trim
• Full Shapes, deep draft
• Ease halyards, Outhaul and Cunningham
– Steering
• Foot off to keep the boat moving. Helm and Trimmers work
together to continually adjust sail and helm to the varying
conditions. As boat speed increases, point a little higher to
make distance toward the mark.
–Move crew to leeward
• Keep the boat heeled so it is ready to take advantage of any
– breeze.
• Light Air, Choppy seas
– Arrgh! This is the worst!
– Foot off, keep boat moving, one wave can stop
you dead in your tracks, and take minutes to get
moving again. Don’t be greedy and try to point
too high.
• Move Crew to Leeward
– – Try to sails from collapsing/flopping
• Medium Air,
– Yeah! This is by far the easiest to sail
– Start reducing draft in the sails (flattening)
• Outhaul
• Halyards (move draft forward)
• Cunningham
– •
• Medium Air, Choppy Seas
– With a continuous breeze, it is easy to get the
boat moving.
– Watch for the waves, if you hit one head on,
you will loose momentum. If you are about to
take a wave on the bow, steer down,
momentarily.
– – Anticipation is key, don’t get caught sleeping
• Heavy Air,
– This is a transition state, most likely the wind
has just come up.
– You will need to reduce, flatten sail.
– Don’t be fooled. This state is short lived. The
waves will likely come soon. Use this time to
– get ready.
• Heavy Air, Choppy Seas
– Reefed main, Tight Halyards, Cunningham
– Small, Flat
• 90% to 110%
• Roller Reefing will reduce sail area, but don’t
expect to point very high.
– Watch out for big waves, they’ll stop you dead
– in you tracks.
• Velocity Made Good (VMG)
– Strong Winds
• Sail more direct course toward mark, Run down
wind, boat speed will be maintained for Best VMG
– Light Winds
• Sail more of a broad reach to maintain boat speed
– for best VMG.
Down Wind Sail Trim
• Loosen most sail Controls
– Ease Halyards
– Ease Outhauls
• Sails will be let out, air flow over sails will be
reduced, Sails will work in two modes:
– Drag Mode: Wind is pushing sails and boat down wind
– Lift Mode: Air flowing over sails produce lift when
– sailing a broad reach
–
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