Competitive Sailing Sailing To Win Yacht Racing

Twist, It’s Importance and When to Use It

Twist, is the relative trim of your sail from top to bottom. Your sail has a lot of twist when the top of the leech is open and when you have a closed leech, this is described as little twist.

The effect of an increase in twist is a reduction of power and reducing twist adds power up to the point where the sail stalls and power drops.

Twist in your sails is necessary because of surface friction. The wind is stronger the higher you go than it is at the surface and this is referred to as wind gradient.

True wind and boat speed combine to create apparent wind and the stronger true wind higher up creates stronger apparent wind and a wider apparent wind angle aloft.

The upper part of the sail must be twisted relative to the lower part to match the wider apparent wind angle up high.

Wind gradient is more pronounced in light air,  and a deep sail shape, used for extra power in light air – is prone to stalling, so trimming with plenty of twist is necessary.

In moderate winds, you can trim harder without stalling flow and this harder trim with less twist adds power and improves pointing.

In heavy air, as the boat gets overpowered, you flatten sails and add twist to spill power.

You sail with more twist in light air and heavy air and the least twist in moderate air.

Generally, less twist will help to point while more twist is faster giving you a wider steering groove. Coming out of a tack, for example, sails are initially trimmed with extra twist to prevent stalling while you are still slow then you trim on as the boat accelerates to full speed.

In waves and chop, you will trim with extra twist to give a more forgiving steering groove as the boat as pushed around in waves.

Reducing twist when sailing in smooth water maintains full power and a high pointing angle. 

Sometimes, as conditions dictate, a combination of twist and flattening is best and one of the challenges of trimming is to achieve the correct mix of power by adjusting depth and twist to match the conditions. 

Your boom vang and cunningham are two other controls at your disposal to achieve balance.



Competitive Sailing Sailing To Win Yacht Racing

How To Sail Fast in Waves and Choppy Conditions

To sail fast in waves and chop you need speed which means powered up sails and footing off in the worst bits.

As you hit each wave it slows you down and sailing well in waves requires determination, concentration and the correct technique.

When sailing in chop, acceleration mode is the only mode and speed breeds speed so the faster you go the more power you have to deal with speed sapping waves and to reduce pitching.

Upwind, you will need to sail lower than you normally would to keep the boat fully powered and drive to keep the jib telltales flowing with the outside ones starting to lift but not stalling.

To power up your sails there are three settings to achieve this being

1.Angle of Attack 2. Sail Depth and 3. Twist.

To achieve depth with the mainsail, straighten the mast, ease the outhaul and soften the luff with a combination of letting the Cunningham go and easing the halyard.

For the Jib, allow the forestay to sag and move the jib leads forward to make the jib fuller. Move them until all the inside telltales luff evenly up the whole luff of the sail.

Trimming the sheet on takes the twist out of the leech and adds power and assists with pointing but be careful not to over trim because you will stall flow which in turn will slow you down.

Creating a little leeward heel can help your performance in chop and create weather helm, which will help you keep the boat on the wind even as the chop tries to push the bow down. (not too much though as too much weather helm creates drag) 

On flat-bottomed boats, the heel can also soften the landing when pitching, concentrate weight low to further reduce pitching and reduce windage.

If you see a particularly nasty set of waves coming, foot off for extra power before you hit them. By sailing low and fast you’ll have extra power to sail over the big ones or steer through them.

Just like going upwind, the first step to downwind performance is to build speed. Head up to a hotter angle with the apparent wind on the beam, this gets the boat moving and establishes flow across the sails.

To build speed, you need to keep the apparent wind forward. Once you’ve got the boat moving downwind, let the apparent wind guide you. Sail as low as you can while keeping the apparent wind blowing in from the side of the boat.

The spinnaker trimmer should provide feedback and if the load on the spinnaker sheet lightens, the trimmer needs to pass that information to the helmsman, “No lower, I’m losing pressure, heat it up.”


Competitive Sailing Sailing To Win Yacht Racing

The Boom Vang & It’s Importance

Depending on the boat you sail, the boom vang will be one of the most important controls to determine the twist of your mainsail. 

As we go from sailing upwind to across the wind and then downwind, the difference in mainsheet tension will determine how much the boom will try to lift as you ease the sheet and this is where vang tension plays its part.

When sailing upwind, different amounts of twist in the mainsail are needed depending on wind strength and sea conditions and as a rule of thumb, in 10-12 knots of wind the main telltale should be breaking 50% of the time and not much or any vang will be needed.

In order to replicate settings for each wind strength and angle of sailing to the wind, it is important to have marks on the vang rope as a reference for the correct amount of tension to control the leech of the mainsail for the current conditions.

When you sail into a lull, the mainsail begins to stall and more twist is needed so the main sheet is eased until the tell tail eventually flies but with the vang on, the mainsail moves to leeward closing the slot. With the vang left slack, the boom is able to rise and the mainsail twists at the top without losing power from the lower sections of the mainsail, and without dropping the boom to leeward and closing the slot.

In light wind and choppy conditions have the vang on hand tight to stop the boom from bouncing but constantly check that your twist is correct by watching your tell tales.

As wind speed increases, the twist is controlled by a combination of sheet and vang tension.

In heavy air where your traveller is completely to leeward and you are still easing mainsheet to keep the boat upright, the mainsail will begin to flap  when the mainsheet is eased. Pull your vang on to tighten the mainsail leech to stop it from flapping while keeping power in the leech. You are in effect driving off the leech of the mainsail.

In these conditions ensure your outhaul and Cunningham are pulled on hard and your backstay (if you have one) is at maximum to flatten the mainsail as much as possible without inverting it.

When reaching, the vang is the main control which effects mainsail twist. As your boom is eased beyond the quarter of the boat, the mainsheet is no longer effective at holding the boom down, so the vang takes over.

On a run, the boom is even further out and the mainsheet is now completely ineffective at controlling mainsail twist, pull your vang on to keep your top batten parallel to the boom and this keeps the mainsail fully projected to the wind.



Small Things Can Have a Major Impact in a Race

  1. Make all your lines as short as possible, this reduces weight and minimizes the number of tangles you’ll get. Use a magic marker or piece of tape to mark important settings on each sheet.
  2. Minimize twists in the spinnaker halyard tail by tying the end to a fixed point. All your halyards, especially the main, will stretch, so you may have to tighten them occasionally.
  3. A rolled sail guarantees it will last longer, take your time and do it right to prevent kinks and bends. If under postponement on the water, roll them up and keep them out of the sun and if you have to leave them up, prevent them from flogging.
  4. Use shock cord to hold hiking straps as close to normal hiking position as possible, this will ensure that you won’t have to reach into the bilge searching for the strap with your toes after every tack.
  5. Wrapping tape around parts of the rigging is really important to stop inadvertent unravelling or pins coming loose. However, seeing little tape ends that have come unstuck and are flapping in the breeze is bad. To prevent this, put silicone sealant over the ends of the tape but make sure you use as little tape as possible.
  6. Adjust your mainsheet cam so the jaws are just below the mainsheet when you are trimming it from a hiked-out position. You want the cam low enough so the sheet won’t automatically go into the cam but you want the cam high enough so you can use your foot to get the sheet in the cam temporarily.
  7. Don’t leave lines in a cam cleat as this wears out the springs. Use metal instead of plastic cam cleats because these hold better and last longer plus you can even sharpen them when they begin to wear.
  8. Clear the weeds from your centreboard and rudder just before the start. On a keelboat, you’ll have to back down to do this. If you have an engine, don’t set your prop too early in light air because you may need some help to get to the favoured end of the line before the preparatory signal.
  9. Read the Sailing Instructions before getting to the starting area. Concentrate on courses, recall procedure, shortened course, protest requirements and any other sections where the committee may have modified standard procedure. Always encourage your crew to read the instructions as well.
  10. Use magnetic tape or yarn for sail telltales and sail repair tape is the best way to stick telltales to the sail. Make it easy to tell which telltale is on which side by using red yarn on port and green on starboard with the starboard telltales a little higher.
  11. Before and during the race, there are certain things you should record for future reference. These include wind direction, the order of marks, compass course to marks, and heading on each tack. Use a grease pencil to write anywhere on fibreglass because it’s easily erasable and still works when the boat is wet.
  12. Sailors, like all athletes, need water to keep from getting dehydrated, get a water bottle with a spout and put it in a place where it’s easy for the crew to reach. Encourage everyone to drink, both before and during the race.
  13. Start the race with your bilge as dry as possible. In windy conditions, if you are planning to sail the race with your thru-hull bailers open, you may have to close them while luffing before the start.
  14. Your best source of good ideas is other sailors. Talk to the competitors in your fleet, and spend some time perusing their boats and their setups. You will definitely come away with a few new ideas, tricks and techniques. FREE BOOK! 49 SAILING SECRETS & TIPS