How to Sail with a Swing Keel | Sailing Blog - Technical Hints and Tips - Sailing Television

How to Sail with a Swing Keel

Throughout our 27 years of international cruising, Sheryl and I have sailed over 100,000 nm and 40,000 of those miles have been sailed on the two lifting-keel yachts - Distant Shores, a Southerly 42 and Distant Shores II, a Southerly 49. Many people have asked what it is like to sail such a boat, how they sail upwind, what to do in storms, what happens if you hit the keel, what to do in huge waves and more.

Sailing Upwind

We always put the keel all the way down when working to windward. Our Southerly 49 draws 10' 3" (3.13m) with the keel down - an extremely deep aerofoil keel. Since the swing keel is also deeper than a conventional keel, it performs well upwind. The design doesn't carry as much weight deep down so the boats aren't as light or stiff as a racing boat, but they do well compared to a standard cruising boat with a moderate keel and offer many advantages to the cruising sailor. As you can see in the photo below, Southerly 49 keel at 10' 3" (3.13m) is a REALLY deep keel!

Aerofoil Keel Shape

Some centreboard boats have a flat board for a keel but the swing keels on the two Southerlys we've owned are both airfoil shaped and perform well upwind. I asked world-renowned yacht designer Rob Humphreys how important it was to have an aerofoil shaped keel. He said, "It’s vital, and not just for upwind performance. A well profiled aerofoil section keel optimizes the lift-drag ratio and widens the stall angle."

Sailing in Shallow Water

Whenever we are sailing in shallow water and there is a chance we might touch the bottom, we look over the chart and raise the keel to a comfortable depth. For example, when crossing the shallow Caicos Bank (photo below) we raise the keel halfway so we draw just 6-7 feet. The boat will still sail well, but she will not point as closely upwind. You can see we are close reaching. It is great to have this ability when exploring.


Lifting the keel can reduce or eliminate the risk of the yacht broaching. According to cruising guru Jimmy Cornell, who owns a Garcia Exploration 45, "continuing to lift (the keel) up to the point where the board is fully retracted, is a great advantage as the risk of broaching is virtually eliminated. The absence of a keel to act as a pivot in a potential broaching situation means that the boat does not tend to round up when, in a similar situation, a keeled boat would do just that. It is a feature that I have blessed on many occasions and that has allowed me to continue keeping the spinnaker up longer than I would have done otherwise."

Ocean Sailing Downwind

Before we sailed a Southerly Yacht across the ocean (we've now done it 5 times), I wondered what it would be like on a boat with a swing keel. Talking with other sailors who owned shallow-draft swing-keel yachts, I realized there were more options for sailing efficiently if you have a lifting keel. Swinging the keel up to raise it means you have actually moved the centre of lateral resistance backwards. It's possible to use this to your advantage when sailing downwind. Normally the yacht designer has carefully calculated the best position to mount a fixed keel. For a yacht with a swing keel, the design is done to optimize performance with the keel all the way down. When we swing the keel partially up, the centre of effort moves aft as you can see in the diagram below. We use this to improve performance when sailing downwind plus it reduces helm effort. It is similar to sailing a dinghy. With the keel most 70 percent raised, we have modified the bottom profile so the boat is more like an arrow. In this position the boat loves to sail downwind!

Distant Shores III

If you are considering buying a swing-keel yacht, please contact us for more information on the new Distant Shores III. She will have a swing keel just like Distant Shores and Distant Shores II and, based on our experience, she will be a great boat for a circumnavigation! We are currently working with a design team to develop this new model - to be launched later this year!

Swing Keel FAQ


Can you sail with the keel up?

Yes. The boat is safe to sail with the keel in any position including raised all the way up. Naturally the boat makes a lot of leeway when going to windward with the keel completely retracted, but she only heels a few more degrees. To understand this you can look at the image below of the keel for our Southerly 49 before it was installed during the build. The keel assembly consists of the massive grounding plate (weight 3180 kilos) plus the swinging keel at 2050 kilos. When you swing the keel up the centre of gravity does raise but not by enough to effect the safety or heeling by very much since so much of the ballast is in the grounding plate. In the picture above we have the keel of our Southerly 42 almost all the way up sailing the shallows of the Bahamas. We are drawing about 4.5 feet instead of our usual 9 feet (2.72m), the deepest draft of the Southerly 42. We are beating upwind and, despite making more leeway than usual, she still makes progress upwind.
Cool Keels - 8

What happens if you run aground?

The keel is designed to swing up into the hull when raised. Since it pivots on its front bearing in normal operation there is no damage if you hit something. Of course we try not to run aground, especially when moving at speed. The lifting pennant goes slack and the boat slows down. This is unlike a "vertically-lifting" centreboard which can be damaged by hitting something as the board jams in its case.

Does the board rattle?

We have never heard the keel move while sailing either of our Southerlys. We do not call it a centreboard since the weight and profile make it more like a regular keel. The swinging keel part of the assembly weighs 2050 kilos (4400 pounds) on the Southerly 49 which is about the same as a BMW 740 automobile! I don't think it could rattle. When we drop the keel down all the way it makes a thump as it comes to rest in the stops in the massive grounding plate.

Does the keel require maintenance?

Yes. The keel lifting mechanism is a system and as such has a maintenance schedule. Once a year we check the hydraulic level, and every five years we replace the pennant that lifts the keel.

Are you considering a Swing-Keel Sailboat?

We're currently developing a new model of swinging keel shallow draft monohull. Distant Shores III be 48 feet long with a draft around 3' with the keel up. If you are in the market for a similar sailboat and would like more information please email us.

In an upcoming blog I will discuss how to sail a swing-keel yacht in heavy weather conditions…

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