shoal draught yacht

What Is Shoal Draft & Why Your Boat May Need A Shoal Keel

The draft of a boat determines the depth of water the boat can be used in. You may be aware of shallow draft, on boats that can navigate very shallow waters, and deep draft, on boats that are used in deeper more turbulent waters, but what exactly is shoal draft?

What Is Shoal Draft?

A) shoal draft allows a boat to pass through shallow waters, b) shoal draft means you are less likely to damage your keel, i) shoal draft boats are not as stable in turbulent waters, ii) shoal draft gives a boat a different righting moment, 1. fin keel, 2. wing keel, 3. bulb keel, 4. catamaran (no keel).

Shoal draft refers to the draft of sailboats that have a shorter type of keel than a boat of similar size. The shorter keel allows the boat to pass through shallower waters than a full keel would. Shoal draft gets its name from the boat’s ability to better navigate the shallow waters found near shoals.

Most sailboats are fitted with a full length keel to give them better stability in deep water, especially when the water is turbulent. They are said to have a deep draft.

Because a a shoal boat has a shorter keel it can access shallower water and is said to have a shallower draft.

Because the keel length prevents the boat from accessing very shallow water, like a flat bottomed Jon boat , it is not a shallow draft vessel.

Likewise, because the keel is much shorter than a full-length keel it is not a deep draft vessel either. We can think of it as a cross-between the two types of draft.

Because a shoal draft boat is used in open ocean water but can also access water near sandbanks and shoals that form in coastal areas, these boats are referred to as shoal draft boats.

Although sailboats that can access shoals are often referred to as shallow water sailboats, every ocean-worthy sailboat will be a shoal draft boat as shallow water boats are rarely fitted with keels (one exception being the canoe ).

Why You Would Need A Shoal Draft Boat

Shoal draft is almost always used to refer to the draft of a sailboat that is shallower than your would normally expect on an ocean-going boat of that size.

Shoal draft allows a sailboat to access the type of shallow waters that a deep draft sailboat would be unable to navigate.

This unique capability has both advantages and disadvantages as we will see.

Before moving on to the advantages and disadvantages of shoal draft though you may want to read the article about shallow draft vs deep draft to get a better understanding of how draft affects a boats performance.

Be aware that shoal draft is not the same as shallow draft. For simplicity terms you can think of shoal draft as referring to a deep draft boat that has a shallower draft than normal.

The 2 main advantages of shoal draft

Below are the two key advantages that shoal draft offers:

• The ability to pass through shallower waters close to shore or submerged banks.
• Less likelihood of grounding or damaging your keel in shallow water areas.

It should come as no surprise that a boat with shoal draft is better equipped to navigate shallower waters than a deep draft boat of similar size.

The boat’s capacity to pass through shallower waters is due to the shorter length of the boat’s keel.

As the keel is the part of the boat that sits deepest in the water a boat with a shorter keel will be able to access water with less depth than a deep draft boat (with a longer keel) would need.

But, why would you need this capability?

Well, if you regularly sail in waters that have shallow areas, or plan to cruise around shallow bodies of water where you run the risk of entering shallow areas by mistake, like the Florida Keys for example, then it would be best to get a shoal draft boat rather than a deep draft one.

Having a shorter keel, and thus a shallower draft, means you run much less risk of damaging your boat on the bed.

Passing through shoals or shallow waters with a boat that has a full keel, and thus a deeper draft, would likely result in the boat getting stuck (best case scenario). Or, the keel can become damaged (most likely scenario).

When this happens the bottom of the boat may also become so damaged that the boat starts to take on water and sinks (worst case scenario).

So, a shorter keel on a boat that usually has a full length keel gives the boat a shoal draft which allows it the ability to pass through shallower waters, such as shoals, more easily and safely.

The 2 main disadvantages of shoal draft

As with everything in life where there are advantages there are also disadvantages.

Below are the disadvantages of shoal draft:

• Not as stable in turbulent waters.
• Different righting moment.

Shoal draft on a boat does give you the advantage of traversing through shoals easier but this comes at the cost of stability in turbulent waters.

Although a shoal draft boat is more than capable of ocean voyages it does not offer the same type of stability as a deep draft boat especially in challenging conditions.

The longer the keel, the more stable the boat is in turbulent water.

The shorter keel on a shoal draft boat means less stability in turbulent waters.

If you plan on taking your boat to deep choppy waters, you might be better opting for a deep draft sailboat rather than a shoal draft one for the extra stability it offers.

This is another stability issue.

The righting moment of the boat is defined as the ability of the boat to maintain static stability.

With a shoal draft, the righting moment of the boat can be compromised because of the shorter appendage of the boat (the keel).

Usually, this is remedied by adjusting the ratio accordingly. This means that to correct the righting moment of a shoal draft boat the keel of the boat must be heavier.

Additionally by lowering or increasing the ballast it is possible to adjust the center of gravity of the boat, thus normalizing the righting moment.

Some boats do this better than others.

The 4 Types Of Shoal Draft Keel

As you know, the keel is the lowest part of a boat that is responsible for maintaining the stability of the boat while it is in the water.

As we have already learned a shoal draft keel is shorter than a full keel in order to allow the boat to navigate shallower waters.

There are several types of shoal draft keels found on boats (and a no keel shoal draft boat). They are:

• Catamaran (no keel).

Let’s take a quick look at these keels now to see how they contribute to the shoal draft of a boat.

This is a variation of the standard deep fin keel but the draft is adjusted by reducing the keel length and profiling the keel to be able to add more weight to the ballast.

A lot of yachts are usually equipped with this or given the option to swap their full keel to this type of keel.

Another variation of this is a fin keel with a retractable centerboard .

This is usually used by people who take interest in sailing because the retractable center board makes it easier to avoid grounding.

This type of keel is usually used on boats with shoal drafts because the wing keel provides a way to be able to reduce your boat’s draft.

Wing keels are usually found on yachts that regularly pass through shallower bodies of water.

This keel gets its name from its wing type protrusion at its tip (as seen in the image above).

A disadvantage to this is that wing keels tend to create a suction effect in soft mud bottoms slowing down the boat or even getting it stuck.

The bulb keel is a type of keel that usually has a high aspect ratio foil that has a ballast at the bulb.

A bulb keel is good when it comes to providing an efficient and effecting righting moment especially when your boat has a shoal draft.

Another good thing about this keel is the fact that it does not often get stuck in the ground but in the event that you do get stuck, it is relatively easy to free.

This makes the bulb keel one of the most suitable and common for shoal draft boats.

Bulb keels also come in centerboard designs allow it to be lifted thus giving the boat an even shallower draft.

The Catamaran is an ocean -going vessel that has no keel therefore it is considered to be a boat with a shoal draft.

A catamaran does not need a keel to be able to stay stable, and not tilt, because of its multi-hulled design which is geometrically stabilized by the two parallel hulls and the wide beam it possesses.

If you would like to know about the different types of shoal draft boats available read our article what is a shoal draft boat .

Mick McGrath

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How keel type affects performance

• Chris Beeson
• December 2, 2016

James Jermain looks at the main keel types, their typical performance and the pros and cons of each

A fin keel and spade rudder configuration gives high pointing but can be sensitive on the helm Credit: Graham Snook/YM

James Jermain has tested hundreds of yachts in his 30 years as Yachting Monthly’s chief boat tester

The performance and handling of a yacht depends on many things, but perhaps the most important single feature is the shape of the hull and the profile of the keel. Over the years hulls have become shallower and keels narrower, but for many types of sailing this progression is not necessarily progress. Of the various shapes that have evolved, each has its own advantages in different circumstances. Here is a run-down of how they may fit your sort of sailing.

FIN KEEL WITH SPADE RUDDER

A low wetted surface area and aerofoil shape means speed and agility

The most common modern option, usually combined with light but beamy hulls with high freeboard.

GENERAL AND TO WINDWARD

• Low wetted surface and good aerofoil shape means good speed, high pointing and quick tacking
• Light steering
• Best designs can slice through heavy seas in reasonable comfort
• High volume, light-weight designs can be lively and tiring in heavy weather
• Flat sections can cause slamming
• Less steady on the helm, requiring more work and concentration
• Strong tendency to round-up when hard pressed
• Generally require earlier reefing
• Can be unstable when hove to
• Quick to surf and may even plane
• Can broach easily and suddenly
• Can be directionally unstable and hard to control in heavy conditions

UNDER POWER

• Handling is precise and turns tight and quick
• Some handle almost as well astern as ahead
• Limited lateral area so susceptible to beam winds at low speeds
• An unattended helm can slam over suddenly

FIN KEEL WITH SKEG RUDDER

The skeg running aft protects the rudder and improves tracking under sail and power

Similar to above but with some key differences.

• Skeg provides better support for the rudder
• Tracking under sail or power is improved
• There is less chance of damage
• More wetted surface so potentially slower
• Objects can get stuck between rudder and skeg
• Limited balancing can make helm heavier

The mass of a long keel is often more seakindly and will carry way well.

The traditional option, usually found on pre-1970s designs.

• Good tracking
• Slow, soft, comfortable motion
• Drive powerfully through short seas but can be wet
• Carry way through tacks
• Resist rounding-up
• Heave-to well
• High wetted surface area and a poor aerofoil shape, so speed reduced, tacking slow, leeway increased and pointing ability reduced
• Long ends can cause hobby-horsing
• An unbalanced hull or rig can cause heavy helm
• Track well and very resistant to broaching
• Very stable in heavy conditions
• Reluctant to surf (a mixed blessing)
• Carry way well
• Track straight
• Heavy construction can reduce vibration and noise
• Large turning circle ahead
• Unpredictable and hard to control astern

LIFTING OR SWING KEEL

A lifting keel enables beaching, but beware of stones jamming the plate

The ultimate shallow-draught option.

• A fully retracting keel offers shallowest draught
• A well-designed lifting keel can be very efficient and fast
• Grounding on anything other than soft mud or sand can damage an unprotected hull
• Stub keels offer better protection but are less efficient and prevent level drying out, except in soft mud
• Stones and dried mud can jam the lifting plate
• Internal keel boxes reduce accommodation space
• Directional stability is poor
• Early surfing and planing
• Control can easily be lost in strong winds
• Good performance and handling with keel down
• Directional control increasingly poor as the keel is raised

TWIN OR BILGE KEEL

A bilge-keeler will dry out upright on a flat bottom

A popular shoal-draught option in Britain, less so abroad.

• Shallower draught
• Dry out upright on a flat bottom
• Good protection when grounding
• Good designs are better to windward than long keels, almost as good as fins
• Pointing and speed to windward is reduced, considerably so in older designs
• When well heeled, waves can slap under the windward keel
• Can topple over if one keel finds a hole or soft ground

Modified water flow over the wing keel foot can give the motion of a longer, heavier boat

Once popular, now largely replaced with various types of bulb.

• Reduced draught
• Low CoG means good righting moment
• Modified water flow over keel foot means greater efficiency and gives the motion of a longer, heavier boat
• More likely to pick up lobster pots, etc
• Risky drying out
• Weed and barnacle growth under wings difficult to remove

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Yachting World

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Jeanneau SO410 review: lift keel opens up options

• Toby Hodges
• October 21, 2021

With its lift keel option, the Jeanneau SO410 has a potent trump card: It has the draught of a Class 40, yet can also nose into the shallows. Toby Hodges was intrigued

Product Overview

Manufacturer:, price as reviewed:.

If you sail in tidal harbours or shallow waters, your choice of midsize new production yachts is more limited than you may realise. While most manufacturers offer a shallow draught version of their fixed keels by adding more weight to the bulb to compensate for the reduction in righting moment, this is not a compromise all sailors are willing to make. Jeanneau, on the other hand, has long offered a lift keel on its smaller models, yet by doing so on something the size of the new Jeanneau SO410, it has established a clever niche.

The Vendée yard certainly didn’t follow the status quo when it developed its eighth-generation Sun Odyssey line three years ago and the Jeanneau SO410 adds to a string of innovations for this latest range.

First came the groundbreaking bow and hull shape, together with the walkaround deck design on the SO440 and SO490. Now comes this lift keel option, which is technically a hinging ballasted keel. It is a similar concept to that employed by Pogo for its performance yachts, yet Jeanneau is the only large scale cruising yacht manufacturer to offer such a system.

Consider the fact that the standard draught of a Jeanneau SO410 is a conservative 2.25m and the shoal keel version just 1.6m deep. Alternatively, this lift keel version reaches down to 2.97m/9ft 8in, which is the draught of a Class 40 race boat and a substantial difference in potential pointing ability. Then, at the push of a button at the helm, this swings up to reduce it to just 1.37m/4ft 5in.

This €20,000 option is therefore a prospective game-changer for those wanting to sail efficiently to windward. For example the owner of the test boat, which is the first lift keel version of this model in the UK, wants to sail regularly from Falmouth to the Isles of Scilly with his large family. So he wants to cut passage times when sailing against the prevailing westerlies yet be able to tuck into the coves on arrival.

We had a brief opportunity to sail his new boat with agents Atlantic Yachts in Plymouth before it was handed over the following day.

Jeanneau SO410 under sail

The SO440 and SO490 were the forerunners for this modern trend in hull shapes and first impressions of the Jeanneau SO410 are of another contemporary, powerful, aggressive-looking design.

This Marc Lombard interpretation continues and refines that full bow, chined and chamfered look – elements which help give maximum internal volume yet keep the wetted surface narrow. The forefoot and first 0.5m below the dreadnought bow is also noticeably dry.

Chines help create volume and stability, while twin rudders give the beamy hull plenty of grip. Photo: Josh Tarr

A bow thruster is an option most owners reportedly take and while that sounds like overkill for this length of boat, I can understand why. The light, voluminous bow gets taken by the wind easily when under motor, which makes manoeuvring tricky, particularly in reverse.

Typical British summer conditions greeted us in Plymouth Sound, with 15-20 knots westerly winds that were really puffy under the dark clouds. It was the first time the boat had sailed, so I was surprised and impressed with how quickly and easily the Jeanneau SO410 found its groove. It never felt pressed and was easy to maintain good speeds (very close to the polars in fact).

We averaged 7 knots beating and 9 reaching. It was also a fun yacht to sail off the wind, deep reaching with the swell, where we nudged 9.5 knots with the Code sail. I was left wanting more, which is always a good sign.

The bowsprit integrates the bow roller, an option needed to keep the anchor clear of the reverse stem. Photo: Josh Tarr

Worthy of note were the form stability of the hull shape and the ability this keel gives you to point high to the wind (tacking through 70°). It remained very light on the helm, yet with enjoyable and direct control. Marc Lombard is a veteran designer of race yachts around this length, so the performance and handling of the SO410 should perhaps come as no surprise.

The grip of the deep twin rudders and deep keel gave me plenty of confidence to sail around the moored yachts in Cawsand Bay. Sailing heeled and powered up on the wind is addictive. The mainsheet and genoa sheets are on neat bridle systems and while the latter allows for adjustment to lead the sheets inboard for tight pointing, the lack of a traveller option means it’s almost impossible to trim the main to a similar high angle.

The deep swing keel lifted. Photo: Josh Tarr

Managing the sheets from the two aft winches is a little fiddly. You need to pre-plan tacks to ensure the new working genoa sheet will be on the correct winch, swapping it with the German-led mainsheet. However, a real benefit the ramped side deck design brings is the option to stand outboard to work the winch yet with the security of over 1ft of bulwark to brace against.

Both sheets on the test boat had clutches, which allow you to free up the winch, but can cause issues for genoa sheets during tacks if accidentally left on. We also found these sheets consistently snagged the forward mast base cleat during tacks, so moving or covering that cleat would be prudent.

The winches and pedestals are positioned right aft to maximise cockpit space, leaving a compact space behind the helms. However, you do have the option to either sit athwartships, or take the unique position of sitting facing forward with your legs outstretched on the side deck.

The resultant cockpit size is impressive, as is the protection afforded by the deep coamings and large sprayhood. There is no stowage for sheet tails so bags would need to be fitted to keep things tidy. Elsewhere, deck stowage is adequate in two shallow bench lockers, a quarter locker and a sail locker.

Jeanneau SO490 down below

The SO410 offers plenty of accommodation options, from two cabins and one heads to three cabins with two heads, and it is arguably the excellent proportions and the amount of space it provides in all areas that help it stand out from the competition.

Spacious, light and airy in the main saloon with a practical C-shaped galley. Photo: Bertrand Duquenne

This space allows for the inclusion of a proper navstation, ample aft cabins and an impressive en-suite owner’s forecabin. The slab topsides between the upper and lower chines helps create the beam in the galley, saloon and forward cabin.

Rectangular berth in the huge forward cabin. The lift keel version angles this berth. Photo: Bertrand Duquenne

Below decks has a modern apartment feel and I liked the fabric on the bulkheads and neat stowage solutions throughout. The central galley configuration, which has a practical C-shape for working at heel, is one of the main differences over the old SO409. It includes a deep fridge and ample stowage.

The door to the forward cabin has been offset to allow space for the keel box, which removes the option of a convertible double berth in the saloon. The central chaise longue is a great feature and makes clever use of the keel box. A very comfortable seat in the heart of the boat, it also extends out flat to make a nice child’s berth. The manual pump for the keel ram is mounted below and there is a spy glass for checking the ram position.

The forward cabin has an intelligent layout too. By angling the headboard and berth against the forward bulkhead it creates room for a proper rectangular berth (as opposed to a typical V-shape) as well as a good en-suite heads and shower compartment offset to port, which is the same size and configuration as the aft heads.

There is also plenty of space and light in the near identical aft cabins, which have low berths, modest stowage, and large side access panels into the engine room. The curved and fiddled joinerwork, notably the central stowage unit between navstation and galley, provide good support when walking around at heel. Dampeners and spacers are used on the soleboards to prevent some creaking, but unfortunately much of the plywood endgrain has been left exposed and unsealed.

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The SO410 has a smart modern hull shape which offers good sailing manners and behaviour, and has been used wisely to create an appealing accommodation layout. It’s another versatile model from Jeanneau, and one with an added twist – a proper trump card option. If you want a 40ft+ production yacht with shoal draught but deep keel performance, this is the only option. It will allow you to effectively take the competition at the traffic lights and claim the inside track, then when you get to your destination you’ll be able to pick the best parking place too.

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Shallow-draft keels are optional on four Oyster models and available in two formats. The Oyster 495 features a fixed shoal keel and the 595CB, 745CB and 885CB feature a lifting centreboard keel. All offer the advantages of shallow-draft cruising.

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What is the Best Keel for A Shoal Draft Boat?

The popularity of our recent discussion of shoal draft boats prompted a dive into the archives on related topics, and we were delighted to see the name Warwick Collins pop up. Collins, the inventor of the tandem or “Collins keel,” died in 2013, but his name frequently appears up in boat design forums today. For those unfamiliar with Collins, he was typical of the eccentric personalities who often rise to the top in the field of sailboat design—a creative genius whose talents spread into a wide range of forums. In Collins case, the pursuits included poet, novelist, evolutionary biologist, and naval architect. And of course, inventor of the Collins keel—a design which incorporated two efficient foils joined by a ballasted foot. Do a Google image search for “Collins keel,” and you’ll see several variations .

The fact that this PS Advisor Q&A from more than three decades ago ( PS January 1989) is just as salient today as it was then (the tandem’s close relative, the canard keel is a fundamental aspect of can’ting keel racing designs today) illustrates how innovation in foil and hull forms still relies as much on the imagination of creative geniuses like Collins as  it does on computer algorithms.

One shallow-draft keel form that this article doesn’t mention is the bilge keel, which is seeing a bit of a resurgence today. Also missing is the ancient leeboard design. If you are the proud owner of a bilge-keeler or leeboard boat, we’d be interested in hearing from you in the comments below, or e-mailing us at [email protected].

Here’s the original excerpt from PS Advisor January 1989, featuring a question from a reader in Tampa, FL, where shoal draft can greatly expand cruising grounds:

I read your comments on the shoal draft tandem or canard keel by the Englishman Warwick Collins. While you praised the keel, you really didn’t answer the main question for those of us who are looking for a new boat with shoal draft.

Which is the preferred keel for shoal draft? Wing? Scheel? Collins? Centerboard? The old-fashioned long, shallow keel?

Part of it depends on the hull. You can’t just stick any keel onto any hull-there has to be a marriage between the two. The long shoal keel, for example, would be a disaster as a replacement for the fin on a typical modem flat-bottom hull, and the fin a disaster on the deeper, round-bottom hull. So the following comments assume that there’s a satisfactory union between hull and keel. Practical Sailor published an in-depth report on keel-hull connections in the wake of recent failures.

We think the Collins or canard keel looks promising, but we’d have to say it is still not adequately proven. It probably does offer better performance than a conventional keel of the same depth, but it’s not clear that its performance is superior to the other shoal-draft options. There’s also a bit of structural concern with the keel, in that it just about has to be made of iron or steel to have sufficient strength. Wing keels have some of the same problem, but a lead version of the Collins keel could probably deform badly in a hard grounding.

We remain skeptical of the wing keel. While a well-designed one can perform comparably to other shoal-draft keels, we see many wings that are questionable. We walked through the New York Boat Show in 1989 with a naval architect who had designed wing keels for the America’s Cup boats, and his judgment was that every wing at the show was poorly done—sometimes appearing less efficient than a wingless keel of the same depth. In addition, of course, you always have the potential problem of snagging lobster pots or kelp, especially with wing keels that have reverse slope front edges (which they apparently need to be truly efficient).

The Scheel keel is pretty well proven by this time. We think it’s a better bet than the wing, if you have that choice, and overall a good moderate design for shallow-draft cruising. Performance isn’t bad-in racing, both PHRF and IMS show that the Scheel keel is about 5 to 12 seconds per mile slower than a deeper fin on otherwise identical boats.

However, we think the best bet is the modern keel/centerboard. Unlike centerboards of 20 years ago, the new ones are very efficient going to windward with the boards down and not all that bad with the boards partially raised or withdrawn into a stub keel.

For the two boats we’ve recently sailed on-a C&C and a Sabre—our impression was that even with the board retracted the boats sailed about as well as comparable wing-keelers or Scheel keel boats. Maintenance, especially keeping barnacles and weeds out of the inside of the centerboard case, is a problem, and the tackle to raise and lower the board is a minor complication in rigging.

But otherwise they seem best—good performance with shallow draft, and excellent performance when you drop the board fully. For people who like getting into the nitty gritty of foil design, designer Eric Sponberg produced an informative analysis a while back. Ralph Naranjo also reflected on keel preferences in his in-depth report on keel design .

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12 comments.

The Horizon Cat design by Com-Pac was a good answer to Florida west coast cruising with all the shoal waters. The stub keel provided ballast and together with a small amount of the bilge, provided the centerboard housing without intruding into the living space. The board is long enough for good lateral resistance and provides easy management with a pennant towards the tip led to a clamshell cleat on the cockpit sole. I have been exceptionally happy with the combination (and the early heads up when I wander into shallow water!).

The keel/centerboard on Little Harbors(Ted Hood Sr)—I had a 38 footer for 14 years–was phenomenal. Go to weather?? Like a bullet. Did 4 Regatta D-Amigos races with her(Galveston /Vera Cruz), 620 NM , hard to weather most of the way into strong S/SE winds . She was in Trophy range in each race. Would have a larger one today except they quit making them and the larger ones were/are very expensive.

I sail an 87 Sabre 42 CB. i love the keel…we can point with newer boats with a deep keel such as a 2003 SunFast 37 with the board down, but only draw 5′ with the board up. Yes there are negative aspects, such as the maintenance issues involved, but for us, the benefits have outweighed the negatives.

Everything is a trade off….Is there the best all around design?

I’m a twin-keel sailor in Southern Florida. I’ve owned and sailed four, a Vivacity 20, a Westerly 25 and a pair of Westerly Pageants (23′). I’m based in Sarasota, on the west coast where the Gulf waters are warm and blue, but the estuarine waters are brown and shallow.

Advantages: Stiff: With a roughly 40% ballast ratio, the boats are stiff and can handle real wind without extreme heel. Shallow draft: The Vivacity drew 2 feet, and the Pageant is 2’10”. And both can be run aground without fear. This makes gunk holing an adventure instead of a peril. And no underwater parts to break or shear. Maintenance: pull up on a scenic sandbar and scrape the bottom, a fun summertime enterprise. Just don’t forget to figure out the tides. Stability: one of the Pageants had a vane-only self steering device, with no pendulum or aux rudder in the water. It once made the 48 hour trip from Sarasota’s New Pass to the Dry Tortugas entirely on the vane. A sheet-to-tiller system is almost as reliable, although with more variation due to “system” lag. Volume: by their nature, twin-keep designs are beamier than similar-sized single-keel designs. This provides separation for the keels. Thus interior space is larger, with more storage bins etc. Strength: most twin-keel boats are British, and are built for use in areas with large tidal ranges. Slips must accommodate serious water level changes, and are expensive to rent. Many twin-keelers regularly “take the bottom” on their moorings, day after day after day, with all the associated pounding. Dry: all four of my boats had bilge spaces so dry I could store postage stamps there. Finding water in the bilge was a rare event, usually due to leaving a port or hatch open in a rain. With a dry bilge, mildew was held at bay if you had some through-cabin ventilation. Posture: sits upright when in the boatyard; no jack stands required. Much better stability on a trailer (use a flatbed if you want).

Disadvantages: Speed: more wetted area, so slower. Over the very long haul, I average about 3 knots for planning purposes. Mind you LWL is about 17 feet. Pointing: doesn’t sail well at the “edge” going to windward. Performs best about 50-55 degrees of the wind. Barnacles: with more underwater surface, more opportunity for barnacles to grow. Racing potential: last place every time.

For family sailing and cruising, we’ve found bilge keelers to be an obvious choice for southwest Florida. They are blue-water capable, but shine in shallow waters. Roomy, airy, comfy. All boats are compromises, and sailors should be serious about what they want to accomplish. My Pageants were designed to take a family of four across the English Channel for a visit to France. While France is a long way from Sarasota, they continue to be seaworthy and sea-kindly cruisers.

Now that is a proper review of a bilge keel, all the main pros and cons broken down, easy to understand and broken down into easy to visualise information. Thanks

Very helpful as I’m looking to trade a Hunter 27 for a twin-keeled boat… Thank you!

What about the swing keel on Southerly boats? Not sure if they fall into the shoal draft category but I find the capabilities of these boats particularly intriguing!

I have had two excellent experiences with low draft boats. The first in a southerly 115, about 35 ft, design Dick Carter. A cast iron slab on the bottom of the boat with two prominent chines could take easily with a shallow draft of 3 ft and then perform even better with a retractable quarter round fin operated by a simple tackle inside the boat. Loved it and loved the downwind reduced resistance that could be measured in almost 1 knot. The second experience was the shallow draft of a 24 ft trimaran ( Farrier 720 trailer tri). This stuck me with multihulls, not because of the speed, but for the ability to navigate shallow waters and hop onto a beach without a dinghy. Unbeatable.

TANZER 7.5 is the best 25′ boat that ever crossed the ATLANTIC with a Shoal Keel? Is this true?

https://sailboatdata.com/sailboat/tanzer-75

I am a yacht designer specializing in shoal-draft cruising sailboats. My designs are all over the world, in the hundreds. These include small craft like sharpies, Sea Bright skiffs and skipjacks, as well as large cruisers up to 75-feet. Most of these are true traditional-looking centerboard designs with long, traditional drag keels, but some have keel-centerboard configurations. I write about yacht design and construction for WoodenBoat Magazine and Professional Boatbuilder Magazine. I have three books in print about boat design, construction, history and cruising. I live aboard a 53-foot ketch with a draft of 3-feet board up, and 7′ 6″ board down. She is an excellent gunkholer as well as a proven offshore sailor.

What is a drag keel? “”A keel centreboard configuration ” means stub keel with centreboard or perhaps a drop/lifting keel that doesn’t swing?

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• San Jose Sailing Club, California, United States

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San Jose Sailing Club

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Qualifying in the Top Nine of the PICYA's 2011 Club of the Year Contest, the San Jose Sailing Club represents a broad cross-section of bay area sailors who find in the SJSC an active community dedicated to enjoying sailing in all kinds of craft, ranging from dinghies to trailerables, to cruisers docked in marinas around the bay.

PO Box 5631

408-873-1811

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http://www.sanjosesailingclub.com/