Strong wind downwind with unstayed Masts, Cat Ketches and Cat Yawls, more safety and efficiency

In general our thinking about angle of heel downwind is passive – however we can take active control – also a neat trick for more power from cat ketches and yawls with or without unstayed masts and for all boats with unstayed masts.

More info about the Goat Island Skiff Plans

I was only able to make the trip because of Chuck and Sandra from Duckworks putting me up and John Goodman, the owner/builder of the Green Goat Island Skiff “GIR”.  It was a particular pleasure to sail with John (left in pic below). He because he is a very good sailor and was interested to make as much from the learning curve the conditions provided as I was.

Though one of the smaller boats in the fleet it was able to perform equal or faster than larger boats.  Part of it is the boat is lighter and simpler than most of the other boats. And it has gained a reputation for high average speed.  The other thing was we were doing something in a very different way to all the other boats.

Strong Winds – Mostly Downwind.
… A good chance to experiment

The winds were strong (25mph – 20knots plus) and from the stern.  It meant lots of high speed running and broad reaching.  Points of sail where control can be difficult as the boats roll around badly as they encounter large waves.

Why sailing by the lee is NOT a no go zone or something to avoid

Sailing by the lee is traditionally something we are all warned about. But getting used to it has really significant handling and safety benefits for boats with unstayed masts.

The more you use it the more understandable and predictable the boat behaviour becomes.

Raceboats with unstayed masts have been using these techniques for years and switch between regular sailing to by the lee sailing continuously on the downwind legs to add speed and control.

Building up experience by sailing by the lee in moderate conditions allows us to really see the different stages and hints that the sail will give you before it does anything silly.

And if you do gybe accidentally, the sail is completely depowered on the other side.

This attitude to by the lee sailing makes gybing safer – Read More!

Goosewinging correctly – sailing fast by the lee in unstayed sailboats

Most sailors have some idea of goosewinging.  Particularly as many boats move to much cheaper and easier to handle unstayed rigs. Many will goosewing when the wind is from behind.  Most do it the wrong way.

Normally the crew will flip the mizzen over to the opposite side.  This is the wrong thing to do for best performance and in many conditions for safety.

A better choice is to allow the mizzen to flip over to the side it wants and forcefully gybe the mainsail to the other side.

The following diagram explains why in most conditions it is better to gybe over the mainsail.

In the left image the mizzen is partially blocking the wind from the mainsail.

In the right the mainsail is completely exposed to fast moving fresh air.  Or, even better, it can be in the stream of accelerated air that passes either side of the blockage caused by the mizzen.  Racing sailors will know a similar effect when you go either side of an island. Or, when there is a big bunch of boats just to one side of direct upwind behind you.

So that is for speed.  But the important thing I want to show is also how it is good for SECURITY and makes sailing faster.

RELATED LINK – All our Lug Rig Articles – over 20 directly useful articles on setting up and thinking about lug rigs.

Control of heel and powering up through sailing by the lee

Because almost all the sailing in the Texas 200 is with strong winds from behind we had hours each day to play with different settings. For years I have used Sailing By The Lee to maximise speed.  But I had heard A second advantage of sailing by the lee has two stages of explanation.  This part also applies to cat rigs that are unstayed.

The diagram above shows what happens to the heel vector as the mainsail is trimmed in and out.  The boat will heel one way when you pull the mainsheet in and the other when you ease it out.

We used this actively when sailing the Goat to give the boat the angle we wanted.  If the boat starts heeling in the wrong way or becomes unstable this method gives you a powerful method to bring the boat upright.

Video showing Active heel Control from a “By the Lee” angle.

We didn’t have to worry about the boat rolling or heeling uncontrollably in the fast running and broad reaching conditions.  In the video I get the windward and leeward side mixed up – very easy to do when sailing by the lee. But it still shows how new to using the method we were.

The reason this is such a powerful method is that at all times the mainsail has full power.  The following diagram shows why.

In the left diagram with the mainsail on the conventional side you can also control the heel by sheeting the mainsail in and out.  However there is a limit because the sail loses its power as it is eased – it starts to luff.  Just when you need the power to pull the boat upright you lose the power to do so.

When by the lee the (boat on the right) power increases dramatically as you trim in the mainsail. The the sail moves from stalled to having smooth flow from leech to luff reversing the normal flow direction.

From a speed perspective it gives control to avoid a nasty roll in the wrong direction. Simply by pulling in or easing the sheet suddenly a few feet. But whichever way you are forcing the boat to heel the mainsail is developing full power the whole time.

This understanding feeds into methods of the “Safe Gybe” – Click this link.

Limitations of sailing by the lee

During the Texas 200 we started off with a fairly gung ho attitude.  “full mainsail or one reef” and then towards the end we were usually deciding between second and third reef.  There was so much power available using this method our normal sailing speed above 8 mph at any time. Most of the time around 10 mph (just under 9 knots) with extended sprints up to 12 or 14 mph.

Here we would ease the mainsail to push the boat upright.

Very good speed for a little boat – and it was consistent speed – not momentary.  The only boats the little Goat Island Skiff was unable to overhaul were the catamarans in the event.

The downside of the by the lee method is as the wind increases there comes a point where the boat is going so fast in the waves that it overtakes a wave at such speed that it digs its nose into the wave in front deeply.  Happily with the balanced volumes of the Goat hull this does not produce any veering or helm loads. Quite unlike 1980s style planing boats that have wide transoms.

If this happened consistently we simply stopped, sheeted in the mizzen to hold the boat on a close hauled course. Then put another reef in the mainsail.

If we were not sure that another reef was the best choice we would gybe the mainsail. Putting the main on the leeward side and accept that the sail would lose power when eased – something we counted on.

Related Article
The Safe Gybe and the Fast Gybe