Bilge keel performance design

[dancrane]

Visiting La Flotte on Ile de Ré this summer, I saw a sporty-looking yacht, bolt upright in the drying harbour...and to my surprise, she wasn't a centreboarder...

...anybody know what the yacht was?

 

[Birdseye]

No. I'd be interested in knowing myself since I fancy changing boat and would like a newish bilge keeler. I really cannot understand why the mass manufacturers arent making bilgies - there are lots of drying moorings and shallow creeks almost everywhere in the world, and in some areas like the Bristol channel or the east coast UK, a deep fin is a real PITA.

 

[dancrane]

That's certainly my point of view, Birdseye. As far as I can see, the only recognisably fine-sailing bilge-keeler which doesn't suffer badly for its practical design, is the Westerly Fulmar.

 

[Tranona]

No. I'd be interested in knowing myself since I fancy changing boat and would like a newish bilge keeler. I really cannot understand why the mass manufacturers arent making bilgies - there are lots of drying moorings and shallow creeks almost everywhere in the world, and in some areas like the Bristol channel or the east coast UK, a deep fin is a real PITA.

Because there is no demand - or rather the potential in our tiny bit of the market is too small to justify making them. Legend tried and failed, and the other builders cater for shallow draft with lifting keels - know it is not quite the same, but the french who have a similar environment of drying harbours and creeks manage quite well. You could of course buy a Sirius or an RM, both of which are available with twin keels. The latter will probably satisfy your performance needs as well. A Sadler 290 would fit your bill as well, if you can find one.

 

[roblpm]

Grrr i never deleted that! I posted that there are quite a few French "biquilles"

http://www.mareehaute.fr/?lang=en

 

[Bru]

Twin keels (two proper foils designed for hydrodynamic performance) have an undeserved reputation for poor sailing qualities due to the dire upwind performance of bilge keels (two slabs of GRP or steel stuck on the hull any old how)

Even the production "bilge" keelers of the sixties and seventies often offer respectable performance to windward but they too are tarred with the same brush as the handful of truly poor designs

Yes, the twin keel Centaurs, Sabres, Sadlers etc will never perform as well to windward as the fin keel equivalents but sailed properly the difference isn't drastic and the advantages of shoal draught and the ability to take the ground can make the compromise worthwhile

As far as new build is concerned, I doubt there's much of a market for twin keelers. New boats are not bought by people looking to save money on moorings (either permanent or visitor), they will nearly always be kept in and sailed to and from marinas

Just for interest (and to show off), my response to people who say "bilge" keelers don't sail to windward is to show them the track log from our sail from Burnham to Bradwell in April this year ..

(Note that the "cutting off" of the track on a couple of the tacks is an artefact of the track logger not logging a position near enough to the time of the tack)

We were beating into the Blackwater with a fair tide of a knot or so, give or take (we crossed the Spitway at nigh on low water IIRC) with two reefs in the main, a big chunk of genoa rolled away and 25 to 28 knots of wind in our teeth. It was quite, erm, lively out there as well!

The engine was off as soon as we cleared Burnham Yacht Harbour and got the sails up and it wasn't restarted until we were within a stone's through of the beacon at the entrance to Bradwell Marina

Now tell me "bilge" keelers can't sail to windward!

 

[Birdseye]

That's certainly my point of view, Birdseye. As far as I can see, the only recognisably fine-sailing bilge-keeler which doesn't suffer badly for its practical design, is the Westerly Fulmar.

+

last boat I had was a Moody 336 bilge and that certainly sailed OK - we raced her and did quite well. The hull was rated as a bit faster than a Sigma 33 which the NHC lists confirm. With decent twin keels underneath she would definitely be at least a match for the Fulmar. Good accommodation too, but a poor cockpit - far too shallow and with main sheet in front of the sprayhood.

But the 336 was one of the very last british bilge keelers built so you would expect it to be better than what went before.

Because there is no demand - or rather the potential in our tiny bit of the market is too small to justify making them. Legend tried and failed, and the other builders cater for shallow draft with lifting keels - know it is not quite the same, but the french who have a similar environment of drying harbours and creeks manage quite well. You could of course buy a Sirius or an RM, both of which are available with twin keels. The latter will probably satisfy your performance needs as well. A Sadler 290 would fit your bill as well, if you can find one.

I dont buy that Tranona. The fact that bilge keelers are now at a premium to the same model with a fin shows that there is demand. And boat building is hardly so mechanised a business that other designs of keel cant be coped with as shown by the French drop keelers. Trouble is, very few drop keelers can cope with a drying mooring.

Legend are still going and making bilge keelers but I would neve consider a Legend whatever keel. And from the numbers sold, neither would most people.

 

[matt1]

This was my "twin fin" Hunter Channel 31 on a typical wind against tide beat down the Western Solent into a force 7. The tacking angle is fairly respectable, even allowing for the tide under the keels, especially considering we only had the headsail up. In fairness she doesn't point quite as well under just the jib and she was a little under powered but we were taking it easy.

 

[Tranona]

+




I dont buy that Tranona. The fact that bilge keelers are now at a premium to the same model with a fin shows that there is demand. And boat building is hardly so mechanised a business that other designs of keel cant be coped with as shown by the French drop keelers. Trouble is, very few drop keelers can cope with a drying mooring.

Legend are still going and making bilge keelers but I would neve consider a Legend whatever keel. And from the numbers sold, neither would most people.

Plenty of demand for old twin keelers for £20 or £30k - zero for £100k, which is just about the lowest price for a new 30+' boat.

Ability to use a drying mooring does not figure on most new boat buyers list of must haves, and shallow draft is catered for with many boats being offered with shallow draft keels and some drop keels.

Twin keels are a peculiar UK phenomenon from the time when three factors influenced the market. First, the dominance of shallow and drying moorings, second n explosion in boat buying and third the introduction of GRP which made twin keels easier to build.

That lasted for about 15 years and all the builders who majored on twin keels rapidly brought in single keel versions or new designs. Why? Marinas, deep water moorings, wider cruising horizons and better performance. No twin keel boats have been built in any quantities in the last 25 years. That is telling us something.

Agree about Legend - but their (largely correct) analysis was that performance was low on the list of priorities in the old twin keel designs, so what was missing on the market was a staid, large volume boat, sort of Macwester on steroids. They were wrong.

 

[HenryEDM]

Lots of French yards do high performance bilge keelers. Check out RM Yachts for example

 

[dancrane]

Interesting thread, thanks for contributions. The following isn't meant to rile anybody, it's just what seems to me to be the way things are, despite publicity-people's deceptive ways.

Mr Tranona has explained to me why almost all the boats I'd like, aren't built...some of the reasoning is excellent, though what it says for new-boat buyers in the UK, isn't flattering.

I can certainly see that anyone buying a costly new yacht is very unlikely to want to leave her on an inexpensive drying mooring...and of course, the manufacturer has no reason to cater for the convenience or economies of his products' third/fourth-hand owners, long after the factory-sheen has worn off, and a large proportion of her initial value too...

...so, long after the ageing fin-keeler's owner wishes he could berth her annually for a small proportion of what he paid for her, her design still requires a pricey deep-water mooring.

That seems unarguable because it's inevitable, if a bit sad, like all those once-grand cars whose resale value today is tiny compared with the cost of any repair to the bodywork, though perhaps it permits low-budget folk to own for a while, some faded, almost-glamorous things. But...

...the reasoning overlooks a basic line of thinking (not exclusively my own, I hope?) which is that in the UK, it is appealing to be able to visit drying harbours, rivers, beaches, etc...

...and the default solution, those delightfully versatile lifting-keel boats, are on close analysis mostly too vulnerable to rocks, wrecks and mooring blocks, to actually leave to dry.

So we have to assume that all new-boat buyers decide like sheep, that they'd much rather be herded into marinas and limited deep-water space, and that they'll cheerfully sign the cheque, acknowledging that all those sheltered shallow blue bays and idyllically peaceful wooded drying creeks are going to be permanently out-of-bounds to their new yacht...

...but surely that isn't the case? I reckon it's generally acknowledged here, that a laughable number of offshore yachts never go offshore...most of their owners are pressed for time, so whatever their ocean-going dreams, they rarely go further than attractive accessible local spots on summer weekends...and what could limit those sites more, than a fin keel?

As I understand it, for reasons of national economic downturn in the nineties, other nations' cheap, fast, arguably appealing, mostly fin-keeled yachts virtually monopolised the new-boat-buyer's choice at that time and since, and thus they now also dominate the secondhand market, despite the high cost and limited choice of suitable berths, and the boats' own uselessness for enjoying so many of the appealing areas on their doorsteps...

...so, the problem isn't that bilge-keelers aren't wanted, but that almost everything we've been offered for several decades has been drawn with a very different, continental type of sailing in mind...and in the virtual absence of a UK small-boat industry, hardly anybody here buys an appropriate boat for the place they'll use it. The marketing men take care to push the performance benefits of a deep fin, they spatter the brochures with images from the Mediterranean scene which these hulls were designed to be at home in...

...and the future of UK coastal cruising under sail is intrinsically limited by the absence of any viable UK industry creating a home-grown, home-focused product. Blooming tragic.

By the by, what is wrong with Legend yachts? I don't admire their styling, but I approve of their designer's breadth of mind.

 

[matt1]

Interesting thread, thanks for contributions. The following isn't meant to rile anybody, it's just what seems to me to be the way things are, despite publicity-people's deceptive ways.

Mr Tranona has explained to me why almost all the boats I'd like, aren't built...some of the reasoning is excellent, though what it says for new-boat buyers in the UK, isn't flattering.

I can certainly see that anyone buying a costly new yacht is very unlikely to want to leave her on an inexpensive drying mooring...and of course, the manufacturer has no reason to cater for the convenience or economies of his products' third/fourth-hand owners, long after the factory-sheen has worn off, and a large proportion of her initial value too...

...so, long after the ageing fin-keeler's owner wishes he could berth her annually for a small proportion of what he paid for her, her design still requires a pricey deep-water mooring.

That seems unarguable because it's inevitable, if a bit sad, like all those once-grand cars whose resale value today is tiny compared with the cost of any repair to the bodywork, though perhaps it permits low-budget folk to own for a while, some faded, almost-glamorous things. But...

...the reasoning overlooks a basic line of thinking (not exclusively my own, I hope?) which is that in the UK, it is appealing to be able to visit drying harbours, rivers, beaches, etc...

...and the default solution, those delightfully versatile lifting-keel boats, are on close analysis mostly too vulnerable to rocks, wrecks and mooring blocks, to actually leave to dry.

So we have to assume that all new-boat buyers decide like sheep, that they'd much rather be herded into marinas and limited deep-water space, and that they'll cheerfully sign the cheque, acknowledging that all those sheltered shallow blue bays and idyllically peaceful wooded drying creeks are going to be permanently out-of-bounds to their new yacht...

...but surely that isn't the case? I reckon it's generally acknowledged here, that a laughable number of offshore yachts never go offshore...most of their owners are pressed for time, so whatever their ocean-going dreams, they rarely go further than attractive accessible local spots on summer weekends...and what could limit those sites more, than a fin keel?

As I understand it, for reasons of national economic downturn in the nineties, other nations' cheap, fast, arguably appealing, mostly fin-keeled yachts virtually monopolised the new-boat-buyer's choice at that time and since, and thus they now also dominate the secondhand market, despite the high cost and limited choice of suitable berths, and the boats' own uselessness for enjoying so many of the appealing areas on their doorsteps...

...so, the problem isn't that bilge-keelers aren't wanted, but that almost everything we've been offered for several decades has been drawn with a very different, continental type of sailing in mind...and in the virtual absence of a UK small-boat industry, hardly anybody here buys an appropriate boat for the place they'll use it. The marketing men take care to push the performance benefits of a deep fin, they spatter the brochures with images from the Mediterranean scene which these hulls were designed to be at home in...

...and the future of UK coastal cruising under sail is intrinsically limited by the absence of any viable UK industry creating a home-grown, home-focused product. Blooming tragic.

By the by, what is wrong with Legend yachts? I don't admire their styling, but I approve of their designer's breadth of mind.

Couldn't agree more. I love to SAIL.. (Eg sail, not motor.......I pretty much sail everywhere!) but I still bought a twin keeler because with young kids I wanted to visit beach areas and dry out so the kids could splash about etc.

Because I love to SAIL, I bought a fast one and then added laminate sails and a folding prop....she is consequently very quick and sails very well in very light airs. I'm often quicker than many fin keelers several feet longer.

The biggest reason I bought a twin keeler was that I wanted to have the flexibility to visit more harbours around the South Coast. So if Cowes is overcrowded on a Saturday, I can choose between Newport or drying out opposite island harbour for example. The boat has been to Christchurch, Lyme Regis, the top of Wareham, Bembride beach amongst other areas (that would have been less accessible, or impossible to a similar sized fin keel boat). I think Tranona is right about the historic reasons about drying moorings (although this was never a consideration for me having a deep water mooring) but I think French sailors have moved on and the increasing number of French twin keelers is probably because they have so many more tidal anchorages / harbours they couldn't visit with a fun keeler.

 

[Tranona]

There are some flaws with your argument, Dan. The reason that twin keels disappeared from the new market was that firstly the sub 30' market for family type boats declined as people got richer and there was an ample supply on the second hand market. Little to do directly with the growth of the European builders. Twin keels were never popular in the 30'+ market where their advantages were less obvious - indeed only a few builders bothered with the option.

Cannot understand why you think that new boat buyers are being forced into particular courses of action or patterns of usage. Most of them are rational and choose based on their own preferences. So, your assumption is wrong. Suggest you sit on a boat at a boat show and listen to what potential buyers are looking for, what they like and don't like. May be nothing like what you (and some others here) would like, but they are the real people with the real money - well some of them anyway - and builders build what they want to buy. When you are holding your £100k in your hand, it is highly unlikely that you would spend it on something that did not meet your needs!

As to Legends, suggest you go on one to get the answer. As with many boats, some good points, but overall not an attractive boat compared with its competitors.

Anyway, this thread started off with performance twin keels and, as pointed out earlier there are several designs available in France, notably the RM range which is once again being actively promoted here. However it has not achieved much in the way of sales despite rave reviews. Perhaps what it says about British buyers is not very flattering! Or rather it is, because for their own reasons they do not choose to buy such a boat!

 

[bbg]

@dancrane,

Dan, there is absolutely nothing to stop you from buying your perfect boat. Specify exactly what you want, retain a naval architect to design it for you, engage a boatbuilder to build it. You can have precisely what you want.

It seems odd to me to lament the absence of a mass-produced boat that fits your perception of the "ideal" boat even though you are not actually in the market for one. Tranona has identified the reasons that they are not mass-produced. Essentially, there is no mass demand for such boats.

It is a bit like lamenting the retirement of Concorde by those who would never have flown on it.

 

[roblpm]

There are some flaws with your argument, Dan. The reason that twin keels disappeared from the new market was that firstly the sub 30' market for family type boats declined as people got richer and there was an ample supply on the second hand market. Little to do directly with the growth of the European builders. Twin keels were never popular in the 30'+ market where their advantages were less obvious - indeed only a few builders bothered with the option.

Cannot understand why you think that new boat buyers are being forced into particular courses of action or patterns of usage. Most of them are rational and choose based on their own preferences. So, your assumption is wrong. Suggest you sit on a boat at a boat show and listen to what potential buyers are looking for, what they like and don't like. May be nothing like what you (and some others here) would like, but they are the real people with the real money - well some of them anyway - and builders build what they want to buy. When you are holding your £100k in your hand, it is highly unlikely that you would spend it on something that did not meet your needs!

As to Legends, suggest you go on one to get the answer. As with many boats, some good points, but overall not an attractive boat compared with its competitors.

Anyway, this thread started off with performance twin keels and, as pointed out earlier there are several designs available in France, notably the RM range which is once again being actively promoted here. However it has not achieved much in the way of sales despite rave reviews. Perhaps what it says about British buyers is not very flattering! Or rather it is, because for their own reasons they do not choose to buy such a boat!

I think you mean RM haven't sold many in the uk? I follow them on Facebook and they are selling multiple 10s of boats a year.

Not many compared to benbavjen but a lot compared to rustler etc.

 

[Tranona]

I think you mean RM haven't sold many in the uk? I follow them on Facebook and they are selling multiple 10s of boats a year.

Not many compared to benbavjen but a lot compared to rustler etc.

I thought I made it quite clear I was talking about the UK market. Well aware that many have been sold in Europe (not just in France), but only a handful have been sold here, and at least one of those has been sold back to France. note that they now offer fin keels and wheel steering which suggests that their original concept has limited appeal and if they want to expand sales they need to respond to what buyers seem to want.

I was having a bit of a dig at Dan pointing out that even when products are freely available it does not mean that people buy them if they do not suit their needs and choose to buy something else.

Pretty sure that there are people in France who lust after a Rustler, but guess that none actually buy one.

 

[dancrane]

I was having a bit of a dig at Dan

Well, I deserved that for writing a 500-word post.

As has been said, the problem, if it is a problem, isn't currently mine...and when it is, I'll want a wheelhouse anyway, so there's another whopping portion of the new-boat market removed from my list for being unsatisfactory. I see my future...it's a Konsort Duo.

But I wonder, twenty or more years hence, when those bilge-keelers (that once routinely dotted the UK's inter-tidal zones) have gone to the scrapyard, which yachts will still permit access to undeveloped beauty spots on our shallow coastline? By current trends, cruising under sail will almost exclusively take fin keelers from one marina to another...

...and while that may be what the overwhelming majority of people who actually order new boats wish for, to my eyes it's terribly limiting and I really hope there'll be alternatives.

Regarding performance, someone drew a distinction between 'bilge keels' as just crude supporting legs, and 'twin keels', whose profile and form had been drawn very skilfully to benefit the vessel's performance. The point was made that the improvement could only continue if twin keelers continue to evolve and be built. Shame if that doesn't happen.

 

[Tranona]

Going off topic in this forum, which is about racing and performance, but it is perfectly possible to access much of the shallower part of our coastline with a boat that does not have twin keels. Remember they were only in vogue for a very short period in the history of yachting, and people managed before they were invented. Look around the east coast and you will see thousands of fin keelers working the tides and making good use of the beautiful creeks and swatchways.

Of course being able to dry out enables one to take greater advantage, but again if you look around, very few twin keelers actually do that.

And design is still evolving. The RM keels are nothing like the typical British keels of 30 or 40 years ago. Also David Thomas designed many good twin keelers for Hunter, some of which are still in production even if their appeal is limited. As I noted above RM now offer fin keels on their boats and it would not surprise me if in 5 years time the twin keels went the same way as the tiller has been replaced by the wheel, at least in the boats in their range above 10m.

 

[dancrane]

Of course being able to dry out enables one to take greater advantage

Credit to you Mr T, for recognising a virtue which your new boat doesn't possess. :encouragement:

I'll look again at the Hunter twins.

 

[bbg]

Credit to you Mr T, for recognising a virtue which your new boat doesn't possess. :encouragement:

I'll look again at the Hunter twins.

Dan, do you recognise that the virtue to which you refer is one that relatively few people value, and that comes with certain drawbacks or trade-offs?

It is nothing more than a design feature that some people will prioritise higher than other features, and others will prioritise lower (or not at all).