Bilge keelers & taking the ground

[Nealo]

There seems to have been a lot of discussion on the forum about the merits of bilge keel boats. One of the advantages, according to received wisdom, is the ability of this type of hull design to take the ground, and therefore reap the many associated benefits.

Bilge keel boats also seem more popular on the East/South East coasts.

I don't know enough about yachting yet to figure this out, but it seems to me that if a bilge keel boat is drying out in sheltered waters, a drying harbour or marina, then fine, but otherwise, unless the sea state is flat calm, surely the swell will cause the boat to "bounce" off the drying surface as the tide ebbs?? This must surely place a lot of stress on the keels, unless the tide goes out really fast and plonks the boat down quickly, or have I got this all wrong? I wondered if the reason b/k boats were more popular in the east was because the coast is more "friendly" so to speak.

If this "bouncing" (for want of a better word) is an issue with bilge keelers, would a long keel boat with drying legs be a better bet in such circumstances, because there is more inherent strength in the part of the hull coming into contact with the drying surface?

 

[Searush]

Believe me, you do NOT want to be on a bilge keeler taking the ground on hard sand with a bit of a wave on the water. The whole boat crashes down & everything rattles, including your teeth & it goes on for around 20 mins or so. Very nasty. But it has only ever happened to me once when I ran aground on a lee shore taking a short cut (when I was young, naive & over confident!)

999 times out of a thousand, I cannot telll when I have taken the ground or lifted off. We often have discussions "Are we aground yet?" "I don't know" followed by rapid leaps from side to side to see if the boat rocks or not. Most harbours & good anchorages are protected well enough for boats to go aground quietly. Even apparently open anchorages will have a bar or offshore sandbank that gets exposed as the tide ebbs & provides superb shelter before one goes aground.

I cannot see that hitting the bottom in a long keeler will be any better whatsoever than in a bilge - or any other boat. Remember many fishing communities beach their boats & drag 'em up a shingle bank above the tideline when ashore. Soft mud helps, but very deep mud can be a problem with splayed keels as there is a lot of suction as the rise & sink which can cause flexing.

 

[Dan the man]

No boat wants to bounce up and down when drying out, for bovious reasons. You are right that a long keel boat is inherently stronger so therefore more suitable for drying out. My father has two wooden boats, one 34ft the other 40 ft that we have dried out frewuently sand shingle seabeds when it has been a bit sloppy, bouncy and the boats are fine, nearly 40 years later for one of them!

My bilge keeler dries out happily even when it is a bit choppy in the harbour estuary, but it dries on sand that is not massively hard. I dont like, and never have dried her out in soft mud, especially if the keels are splayed out slightly, for logical reasons when the keels sink into the ground, and rise again later.

If you do have legs, they want to be a bit shallower than the actual keel so as the boat rocks side to side they dont dig into the gorund....I guess you let her settle and then lower then if unsure.
I guess, dont dry out when it is choppy, in my view.

 

[vyv_cox]

A long time ago, not long after we started cruising, a bilge-keeled Westerly Discus sunk on her mooring in Beaumaris when a bilge keel punched right through the hull. A rather large boat to dry on every tide but a warning of what can happen.

 

[MoodySabre]

Bilge keelers are popular on the East coast because there are lots of drying moorings. There are also lots of sandbanks and bilgekeelers draw less. Most are built to withstand the pounding whilst drying out, and as you have said, the ground is usually fairly soft if not just plain muddy.

 

[Searush]

A long time ago, not long after we started cruising, a bilge-keeled Westerly Discus sunk on her mooring in Beaumaris when a bilge keel punched right through the hull. A rather large boat to dry on every tide but a warning of what can happen.

That is not usual. I would expect there to have been a build issue with that. There are many W33's of various models that have dried every tide for a score of years or more without incident. There are a few Centaurs that have suffered keel flexing due to deep mud & lack of adequate internal strengthening. I also understand some Fulmars have had keel issues from design problems. But it isn't a general problem.

 

[Seajet]

You are quite right in your concern; as Searush said, drying out on hard sand, even with just tiny ripples in the water, is heart-stopping.

At my moorings it's soft mud, the twin keelers settle happily, though not often completely upright as the mud varies in consistency ( there are plenty of Luftwaffe bomb craters which have filled with softer stuff, even now ! ) and the wind will probably be blowing on one side, heeling her a little as she settles.

Some of the club twin keelers do suffer keel flexing, nothing drastic though; considering the loads on splayed keels going in & out of mud twice a day all season it's not surprising.

Twin keelers generally offer the most user-friendly, least hassle option, though there is a performance penalty of course; just how much depends on how good the designer is.

Incidentally don't be tempted by any boat with vertical twin keels, it'll sail like a brick; splayed keels are for a good hydrodynamic reason.

There are of course wing keels; some boats settle, usually on more firm ground, on these, often with twin rudders to offer some stability aft.

Some peope are happy with this - not so often for everyday moorings as drying out when the crew are around - but personally I hate this idea, the wing keel is a relatively tiny footprint, and it's a horrible load on the splayed rudders.

Part of the idea is to have twin rudders so one is always immersed as the boat heels, but with a normally proportioned boat this shouldn't be an issue.

Also if one goes aground accidentally in a wing keel boat, there is a significant danger the wings will tip the boat over a very long way, risking her filling up as the tide returns.

I get around all this by having a central lift keel. These have their own problems, as in they involve moving parts, but do offer better performance than twin keels.

I am lucky with my ( Anderson 22 ) keel, in that it's well designed, there is a large streamlined 900lb ballast bulb on the end which stays outside the boat, but is veed on top to fair in with the hull & prevent small stones or mud intruding.

The keel - the plate itself is 3/4" galvanised steel in a tapered section - is raised and lowered by a simple ( and replaceable ) manual winch in the cabin.

The ballast bulb sinks into mud, and the boat remains upright; on hard sand she would heel 20 degrees, but for the reasons given above I avoid drying on hard ground like the plague.

Some other lift keelers have a lot of trouble with stones etc jamming the keel, and designs which leave a flush bottom with the keel raised risk the hull settling on protruding stones, the mooring sinker, etc.

A long keel with legs is really only for very settled conditions when her crew are present; horrible twisting forces can be exerted on legs, not only collapsing the legs allowing the boat to fall or dry on her side, but also risking tearing out their hull attachments.

In some places like Looe in Cornwall or St.Helier old harbour in Jersey, boats with single keels are actually 'docked' into very sturdy floating cradles, which then settle on fairly firm ground.

Of all these, a good twin keler is the minimum hassle, accepting some performance loss, unless one has to reinforce the keel stubs and periodically tighten keel bolts !

Incidentally, to be pedantic 'bilge keels' are steadying keels, often just steel plates, to keep a boat with a central ballast keel upright; boats designed from the outset to have two ballast keels, usually more modern, are 'twin keeled'. Most people including me mix the two terms interchangably though !

 

[Zagato]

There seems to have been a lot of discussion on the forum about the merits of bilge keel boats. One of the advantages, according to received wisdom, is the ability of this type of hull design to take the ground, and therefore reap the many associated benefits.

"One of the advantages", are there any more advantages? The more I read the more single keel boats seem to be such an advantage especially encapsulated ones. No keel bolts, no stress cracks, deep bilges, superior sailing etc.

I have to say I thought I would never buy anything with a long keel for the very reasons you give let alone cheaper mooring costs. My draft is only 3" 9" but I am going to be mildly terrified of running aground in Chichester Harbour - you are stuffed if you do! I have a VERY low freeboard (Folkboat!) and would presume if it falls over it will be submerged when the tide comes in . I don't think a depth sounder will be much help either as it wouldn't give you enough warning!

I suppose if you know the terrain, can afford the moorings and are a purist sailor wanting the best performance it would be a single keel every time and my concerns would not be a problem.

 

[Nealo]

"One of the advantages", are there any more advantages? The more I read the more single keel boats seem to be such an advantage especially encapsulated ones. No keel bolts, no stress cracks, deep bilges, superior sailing etc.

Advocates of bilge keelers generally cite lower draught, less rolling, and not likely to be "tripped" by steep waves (compared to fin keelers) although I think I am right in saying that the last point has been rendered less relevant by modern designs?

 

[Zagato]

I have just read somewhere that bilge keels rolled more than long keels but this was when it was on a mooring not sailing. I bet there are some very long threads on here about this

 

[Haven't-a-Clue]

Right, cards on table: I have a Colvic 26 encapsulated vertical keels and to be fair, upwind is not her forte, 42-43 degrees (where is that symbol?) is her limit. On a beam reach, however, a different story, hull speed achievable in 15 kts or more under the (admittedly!) oversized genoa. But I digress, beaching her as I did for the first time a couple of weeks back, all went well and I was lounging about waiting for the tide with a glass of wine and a book when I got up to get another glass and she rocked an hour earlier than I expected. This was way up the Hamble so apart from the occaisional wash, no waves to worry about. I expect it would be a bit bumpy on an open shoreline, but I ain't ready to do that yet! well not intentionally. I would therefore agree with Searush, most of the time you'll find it difficult to tell when you ground and float off. Pick your spot and away you go.

 

[Searush]

FWIW, both my yachts have been twin keelers & I have had one or the other of them since 1981. There are a number of benefits; drying upright is critical where I sail (with a family crew) as we regularly dry out on lovely beaches with the grandchildren. Spending 3 hours on your ear with young children aboard is definitely a no-no! In crowded anchorages I can anchor inshore of everyone else because it don't matter if I misjudge it slightly. I can take chances crossing sandbanks (if sheltered!) cos I draw less & if it goes wrong it's no problem.

Cleaning the Barney Kulls off the hull can be a bummer as you have to lie on the ground to get between the keels, but see how you get on with a lift-keel - it would have to be in a cradle! Winter storage is a doddle, lift it out & drop it on a couple of wood blocks - end of problems, & damned unlikely to get blown over.

When it's going like a train, the kids like seeing the windward keel just below the waves. But you may get some slamming in short steep overfalls if the hull is flatish between the keels.

Over the years I have occasionally hit a rock or wreck - twin cast iron keels can take quite a clout without any damage & tend to protect the rudder too (although this can't be guaranteed!)

 

[dylanwinter]

no guarantee

I sail a mirror offshore

 

[dt4134]

Couldn't you just put really big springs on the bottom of the bilge keels to absorb the shock?

A sort of amphibious space hopper.

 

[Ubergeekian]

In some places like Looe in Cornwall or St.Helier old harbour in Jersey, boats with single keels are actually 'docked' into very sturdy floating cradles, which then settle on fairly firm ground.

Years ago I looked at a Hunter 490 in Aberystwyth harbour whose owner had made a bra for it. Well, that's what it looked like to me. The 490 has the same keel arrangement as the Anderson 22 - same designer - so if it dries out it heels a fair bit. The chap in Aberystwyth had two wide profile car tyres connect by about 2' of rope and with ropes up each side. They were left attached to the aft rope of his fore-and-aft mooring. When he moored he pulled them under the hull with one rope coming up each side and attached to cleats in the cockpit. That put one fat tyre under each side of the hull, just behind the keel, and kept the boat more or less level when she dried out.

It was a lot simpler than my rather long-winded description, and it worked very well.

 

[sighmoon]

I've only ever dried out accidentally(!). First time was in a full keeled classic, and second in bilge keeler. Both were in East Cost mud, and both dried at a bit of an angle (the mud being deeper where we dried out the classic). I wouldn't really do it by choice, because you can't wade through the mud and nip ashore. Different matter on sand though.

I wondered if the reason b/k boats were more popular in the east was because the coast is more "friendly" so to speak.

What does "friendly" really mean in this context? Would friendliness not extend to single keels?

 

[barnaclephill]

Cleaning the Barney Kulls off the hull can be a bummer as you have to lie on the ground to get between the keels, ...

Searush, I've found that a garden hoe (the one with the 90 degree head) on a 5-foot handle reaches between the hulls to get most of the barnacles off. With the hoe, you can kneel instead of lie, so it can be cleaner on the body. It doesn't seem to do as good a job as a paint scraper, but there are places where I wouldn't feel safe risking getting caught trapped partly under the boat. I've found a good careening spot - 2 inches of mud over hard scoria, in a sheltered drying channel.

 

[savageseadog]

Beaumaris Bay on the Menai Strait as already mentioned has quite a large collection of bilge keelers on drying moorings. Watching and hearing them grounding as the tide falls on a strong North Easterly would put anyone off buying a bilge keeler.

 

[Seajet]

Ubergeekian,

For you ad anyone else possibly interested, an Anderson 22 in her floating cradle at Looe.

The cradle ony just shows, as it was not the subject of the photo' when her owner took it.

In case of interest, you'll probably spot she has a non-standard but rather splendid stainless stem fitting, which incorporates the forestay tang fix essential on this design.

She also has a built-on stainless 'A' frame, allowing quick singlehanded mast raising and lowering.

When she was on this mooring at Looe ( a previous owner a while ago; she is for sale now if one sees www.anderson22class.co.uk as the initial sale fell through ) - she was upstream of the bridge, so to go for a sail he had to lower the mast, go under the bridge, raise the mast, go for a sail, then do the lot in revers, before docking the boat !

 

[reginaldon]

Apart from one drop keel, we are all bilge keelers in the half tide harbour, which goes from sand to mud; virtually no one has any problems apart from a couple that settle nose down or nose up.