The Joy Of Ketch

Experiences with a Ketch Rig

At the end of our first season cruising aboard Speedwell of Rhu it seems like a good time to write something about our experiences of sailing a ketch rigged yacht. We've found that the rig is very flexible and well suited to our style of sailing, but before describing some of the reasons for this it's worth considering why, if it's so good, the ketch is so uncommon in current production yachts.

Why is the rig out of favour?

The ketch rig was a much more common option twenty or thirty years ago than it is now. It was often used to split a large sail area up into smaller, more manageable pieces. As sail handling equipment has improved it has become possible for even very large yachts to carry all of their sail on a sloop rig while still being manageable by a small crew.

I'm not aware of any modern racing yachts that carry a ketch rig. For a given sail area a sloop will be more efficient than a ketch. The sloop is taller, giving a higher aspect ratio to the rig, and a taller main mast can set a larger spinnaker for off wind work. Close hauled performance is particularly important for the racing sailor and a ketch suffers compared to a sloop hard on the wind because its mizzen gets back-winded and ends up creating drag rather than contributing any power. The racing world influences production yachts, partly through fashion and partly because many yacht owners indulge in some club racing and so are looking for a boat that will perform around the cans as well as going cruising.

A second mast adds not just the mast but also additional rigging, structural reinforcement for the mast step and standing rigging, extra winches for the mizzen and restrictions to the possible deck layout. All of this is extra expense that the highly competitive volume yacht building business can't justify now that powerful winches and modern sail furling options enable large single masted rigs to be relatively easily handled. I think that the extra expense is probably the biggest factor in the unpopularity of multi-mast rigs.

Our ketch rig experiences

First of all I should state that we are cruising sailors, we don't race. We enjoy making the boat sail well and making good passage times but we want to do this in an easily handled and flexible boat. I expect that a sloop rigged Oyster 435 would be faster than our boat on most points of sail, and certainly not slower. However ultimate performance isn't the only criterion in choosing a boat, a deeper keel, lighter weight, broader beam and maybe water ballast in a similar sized boat would give better performance that a sloop rigged Oyster 435 but few people would want to live with an extreme racing machine so we have to accept that there are always compromises when choosing a boat.

Probably the best way to illustrate what we like about the rig is to describe how we sail it in different conditions.

Getting under way

When we're at anchor or on a mooring and lying head to wind (as is often the case) we'll raise the mizzen before getting under way. If we're motoring out of the anchorage we'll get into clear space under engine then unfurl some or all of the genoa to get sailing. If we want to raise the mainsail the boat will comfortably sail to windward under genoa and mizzen while we do the hoist. In this configuration the main boom is off slightly to leeward away from the helm. The boat's motion is more comfortable close reaching than motoring into the wind and there's no engine noise, so working on deck to raise the main is more pleasant (our mainsail handling is at the mast).

If we're setting off from a marina berth we'll normally get the mizzen hoisted as soon as possible after getting going. It's an easy sail to hoist from the cockpit and then it's a simple matter to get some genoa unfurled when we've got space to start sailing.

Light wind sailing

By light wind sailing I mean conditions where the boat will happily carry full sail.

We try to plan passages to avoid lots of close hauled work but if we do need to be hard on the wind then the mizzen gets back-winded by the air coming off the leach of the mainsail and doesn't provide any power at all. Close hauled it's best to drop the mizzen and just sail under genoa and main. In this configuration we're setting less sail than an equivalent sloop so can't expect to make as good a speed, having said that Speedwell has an easily driven hull so she's no slouch close hauled. A cutter rigged boat may not be able to set its staysail when hard on the wind so our windward performance probably isn't too far off a similar sized cutter.

Easing sheets onto a close reach we can set the mizzen and benefit from our full sail area. As soon as the mizzen comes into play we've got a powerful boat trimming tool available. Because it's well aft small changes in mizzen trim can make a big difference to the boat's balance. This makes it easy to set the boat up with just a touch of weather helm. As well as making life nicer for the helmsperson a well balanced boat will sail faster (less drag from the rudder).

As an exercise in using the mizzen to trim the boat we sailed across the sound of Jura on a close reach with the wheel locked, making course changes by sheeting the mizzen in and out.

Reaching is most people's favourite point of sail and a ketch performs well on a reach, with the mizzen contributing to the driving power and providing trimming options to keep the helm light. I've heard it argued that because the overall sail plan is lower down on a ketch than an equivalent sloop the ketch is able to carry full sail at slightly higher wind speeds, but I've not had any opportunity to do side by side tests so I can't confirm or deny this. On the other hand in lighter winds a sloop's taller rig should catch stronger wind further from the sea surface so the actual performance difference is likely to depend on conditions on the day.

On a dead run we'll goosewing, with the genoa on one side, the main on the other and the mizzen on the same side as the genoa. The mizzen is far enough aft for it not to disturb the genoa too much and the boat seems to sail a little better in this “wing and wing and wing” configuration (at least it looks good and may make a few people stop and think to work out which tack we're on...).

Windy weather

The use of foresail and mizzen (“jib and jigger”) in heavy weather is often cited as an advantage of a twin masted rig. We've not yet had Speedwell out in really heavy weather and we're trying our best to avoid it (I'm writing this at anchor in Tobermory harbour sitting out a gale) but I expect we'll get caught out one day. However we've found genoa and mizzen to be a very comfortable sail configuration on strong wind or blustery days.

We can set our mizzen and unfurl our genoa from the cockpit. The genoa sheets are handled by large winches and the mizzen sheet load is easily handled on its 3:1 purchase even in strong winds. With the main stowed there's no worry about injuring the crew with accidental gybes.

Under genoa and mizzen Speedwell will make good progress to windward, pointing a little lower than under genoa and main but still making between 35 and 40 degrees to the apparent wind. With the genoa and mizzen at opposite ends of the boat there's no slot effect so this configuration isn't as efficient as using the mainsail, but on a windy day we're generally more concerned with de-powering rather than powering up the rig so the lack of a decent slot isn't a problem.

On a reach Speedwell will make 7 or 8 knots in a force 6 under reefed genoa and full mizzen with a light helm and little fuss. That suits our cruising style.

Shortening and dropping sail

When we need to shorten sail we've got a number of options. Rolling away some genoa is usually the first choice. The next step is either to drop a reef in the main or stow the mizzen, which we chose depends on the conditions and point of sail but as the mizzen is easily handed this is often our first choice as it comes down quickly and can equally quickly be re-set should we need it later.

Although we've got three reef points in our mainsail so far we've not used the deep reef, when we need to take a lot of power out of the rig we drop the main completely and hoist the mizzen (if it's not already up). We have a reef point in the mizzen as a further step though we've yet to use that in anger, I expect that we'd also be setting the storm jib if we get to that point.

When we're dropping sail at the end of a passage and we've got all three sails up we drop the main first, sailing the boat at a close reach under genoa and mizzen (the reverse of our normal hoisting procedure). The main drops nicely into its stack-pack and the boom is off slightly downwind so the reefing pennants don't end up falling down around whoever is on the helm. As with the hoist the deck is a nicer place to work sailing on a close reach rather than motoring to weather.

Other sails

We can set a cruising chute in place of the genoa in the same way as a sloop (though of course we also carry the mizzen in this case). We don't currently have a spinnaker but I can't see any specific issues with flying one on a ketch.

Other ketch owners speak highly of a mizzen staysail in light airs. On Speedwell we've got a wind turbine on the mizzen mast and a triatic stay that joins the mizzen mast some way below the mast head so there are too many possibilities for a nasty snarl up for us to try one out.

Other uses

Riding Sail

At anchor we have the option of using the mizzen as a riding sail to keep the boat head to wind, either to point into swell or to make the boat sail around less on a gusty day. We raise the sail then tie the boom off centrally using a rope running from one aft cleat to a clove hitch on the boom then off to the other aft cleat (this holds the boom more firmly amidships than just cranking the sheet on hard).

When a gust hits the bow initially blows off a little but that brings the wind around to the side of the mizzen sail which then pushes the stern away from the wind and straitens the boat up. The boat still veers around in gusts but much less than it does with no sails set.

So far this isn't something that we've done much, partly because we've not needed to and partly because there's a trade off between controlling the boat's motion and noise from the sail as it tacks on its batten cars in gusts (perhaps a partially battened sail would be quieter in this case).

With the Engine

Setting the mizzen moves centre of windage further aft and helps to reduce the tendency of the bow to blow off on a windy day. This can be handy when manoeuvring under power if we have to reverse the boat any distance with the wind on the bow (we don't have a bow thruster and our long fin and full skeg make the boat less handy in reverse than a short fin and spade rudder boat).

Crane

We use the mizzen boom and sheet as a crane to get the tender or other heavy items on and off the boat. We've fitted a snap shackle to the mizzen sheet's lower block so that it's easy to unclip from the deck. With the boom supported by its topping lift we can hoist the load on the sheet then swing it in or outboard on the end of the boom.

Antenna Mount

The mizzen mast is a handy place to fit various pieces of kit. We've got our wind generator on our mizzen, keeping it out of the way, together with our radar scanner, radar reflector and a few antennas.

Aesthetics

And finally: I happen to think that a second mast makes Speedwell look like a proper cruising boat, but other people will, I'm sure, have different opinions.

Conclusions

We've found our ketch rig well suited to cruising short handed. The mizzen sail gives us a lot of flexibility in the amount and configuration of sail that we set as well as making it easy to trim the boat. Because the mizzen can be quickly and easily hoisted and dropped from the cockpit it's usually the first sail that we set and we often sail the boat on just genoa and mizzen. When we need more power we can hoist our mainsail with the boat sailing comfortably on a close reach and under all three sails she looks her best.

Articles Index



© Copyright