jaguar 22 swing keel

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pidy

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Hi.

Is it ok to sail without the keel down. What I mean is, does the keel in the down position contribute to much of the ballast weight?

I have sailed in a harbour quite a few times and would like to venture out into the solent. I understand the principle of the keel but I have not had any trouble sailing with it fully retracted.

I know that wind could and may be slightly stronger out in the solent so will in turn cause the boat to keel over more, but how much does the keel retracted counter this.

Thanks in advance for your replies
 
Drop the keel right down. It's only a few feet. If it's that shallow that it grounds you shouldn't be there. :)

The real answer is of course that you'll make dreadful leeway without the keel down. Sailing will be a desperately futile activity.

I take it you don't have a lot of experience. Perhaps find a more experienced sailor to come with you.
 
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pidy said:
Hi.

Is it ok to sail without the keel down. What I mean is, does the keel in the down position contribute to much of the ballast weight?

I have sailed in a harbour quite a few times and would like to venture out into the solent. I understand the principle of the keel but I have not had any trouble sailing with it fully retracted.

I know that wind could and may be slightly stronger out in the solent so will in turn cause the boat to keel over more, but how much does the keel retracted counter this.

Thanks in advance for your replies
Click to expand...

Why don't you want to put it down?
 
Welcome to the Forum pidy.

As others have said drop the keel down. You need the resistance of the keel 'pushing' against the water to counteract the force of the wind 'pushing' against your sails in order to translate the force of the wind into movement forwards. Without the keel you will go sideways (leeway), and become confused because the boat will be pointing in one direction and travelling in quite another. It is not about ballast or the location of ballast, it is about surface area and shape below the waterline.

I am also wondering why you have been sailing so far with your keel retracted?

Cheers
 
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pidy said:
Hi.

Is it ok to sail without the keel down. What I mean is, does the keel in the down position contribute to much of the ballast weight?

I have sailed in a harbour quite a few times and would like to venture out into the solent. I understand the principle of the keel but I have not had any trouble sailing with it fully retracted.

I know that wind could and may be slightly stronger out in the solent so will in turn cause the boat to keel over more, but how much does the keel retracted counter this.

Thanks in advance for your replies
Click to expand...

The keel is the ballast weight isnt it? Or is there other internal ballast that I cannot find mentioned anywhere.

I think you will find that the keel weighs about 250kg. When lowered it will have a significant increase righting moment compared with when raised.

Lakesailor and bitbaltic may both be a little pessimistic about the amount leeway the boat will make with the keel raised as a good proportion of it remains below the bottom of the hull even when raised. Nevertheless Id expect to see significantly less when fully lowered. The whole dynamics of the thing will be different.

Get the keel down. Try it in the deeper parts of the harbour and then go out to sea on a day when conditions are moderate. I think you will find the handing and performance will be transformed.
 
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VicS said:
Lakesailor and bitbaltic may both be a little pessimistic about the amount leeway the boat will make with the keel raised as a good proportion of it remains below the bottom of the hull even when raised.
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Considering the flack even bilge-keelers get for leeway I can't see sailing a swing keel boat with the keel up being very satisfactory.
 
I agree with VicS. You will find that on any course other than close hauled the keel position will make little difference to the amount of leeway. It will make some difference to the stability, the lower the keel the more righting moment it will provide. Sailing upwind, close hauled, I suspect you would find you need the keel down to make satisfactory progress.
Even with your keel right down and drawing 5ft there aren't that many bits of the Solent that you need to avoid. If you run aground with the keel fully down you know you have still got 3ft of water left to sail in if you raise the keel. A swinging lift keel is an excellent echo sounder that rarely suffers damage, I've thanked mine on several occasions.
If you can successfully sail around in the harbour then I'm sure you will be perfectly OK out in the Solent.
 
As VICs says and as you can see from the pic even with the keel up most of it is still there resisting leeway.

I had a Jaguar 22 and it sails fine with the keel up; just heels a bit more.

But I would always sail it with the keel down, that way I would not worry about getting caught out in skinny water. If the keel clonks just wind it up a bit and you are free.
 
In answer to OP question. Even if the keel area exposed to the water stays the same it will work better if down. It will go from a low aspect ratio keel when up, to a high aspect ratio when down. This is all about the water flow from one side to the other when the keel is working to hold the boat against the side pressure of the wind. The high aspect ration (down) has a large area compared to the small end plate area where water can go across the end so less drag. When the keel is up (low aspect raio) there will be much more tendency for water to flow from one side to the other. This flow causes drag and diminishes keel effect. So it will sail better to windward when down. Obviously many boats rely on a shallow keel and the hull to provide resistance to leeway and they can be sailed OK but a deep keel is far better.

Regarding righting power or stiffness. ie resistance to heel. With a little heel on the boat the righting power comes from what is called form factor. This relates to the way the boat sits up on its chine (if it had one) The volume of hull at the curve from flat bottom to sides. Sitting up on this part of the hull the weight of the boat is along the keel line but the centre of buoyancy is off to one side. This provides a lot of righting power. The total weight of the boat provides the righting power. Think catamaran here as an extreme case of form factor righting power.
In any keel boat the pedulum type force of the keel not being vertical is not significant until the boat leans a lot ie past 45 degrees. As the boat leans more the mass of the keel and especially if that is down low on the keel tends to right the boat.
So you will find that the stiffness of your boat with keel up for small degrees of heel will not be much different to stiffnes with it down. However if the boat heels a lot ie to knock down then the keel extended will have a lot more effect in righting the boat.
This type of boat is built in Oz and one of the requirments of the trailer sailer association is that the type be self righting with keel retracted.So it should be OK either way.
If you were really keen you could try a pull down test. Here the boat is tethered bow and stern and pulled down by the halyards to horizontal. To meet Oz ocean racing requirements Cat 5 or higher you would need to have more than 35kgs of force at the hounds (top of the stays) to hold it down. This test done with no one on board. People in the cockpit make a lot of difference to righting moment.
If you OP are sailing very sedately with no spinnacker then I think you will be safe fromn capsize with keel up. (not so with keel removed) good luck olewill
 
Lifting keel boats are supposed to be sailed with the keel down all the time. They have the advantage of being able to lift the keel so that they:

  1. can moor in drying harbours
  2. can sail on very shallow water
 
VicS said:
The keel is the ballast weight isnt it? Or is there other internal ballast that I cannot find mentioned anywhere.

I think you will find that the keel weighs about 250kg. When lowered it will have a significant increase righting moment compared with when raised.

Lakesailor and bitbaltic may both be a little pessimistic about the amount leeway the boat will make with the keel raised as a good proportion of it remains below the bottom of the hull even when raised. Nevertheless Id expect to see significantly less when fully lowered. The whole dynamics of the thing will be different.

Get the keel down. Try it in the deeper parts of the harbour and then go out to sea on a day when conditions are moderate. I think you will find the handing and performance will be transformed.
Click to expand...

Having seen one out of the water this winter, with keel raised, there aint much protruding.
However, it can be sailed much like a large dinghy, adjusting drop keel as appropriate.
 
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alant said:
Having seen one out of the water this winter, with keel raised, there aint much protruding.
However, it can be sailed much like a large dinghy, adjusting drop keel as appropriate.
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The diagrams I have found seem to show a good proportion of it still below the bottom of the boat.

TQA says he owned one, agrees and says it sails fine with the keel up, just heels more


The OP seems to find it sails Ok with the keel up too.
 
Lakesailor said:
Seems pointless fitting the swing bit at all then..........

.
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I dont think anybody is suggesting it wont sail better with the keel down.

One thing for sure is that with it up its going to heel more, although its low ballast ratio is going to make it a tippy little boat I think even with the keel down.
 
Its a 500 lb keel (others may have already explained this...if so , sorry) which lies partially outside the hull when up. It sails brilliantly downwind like this, acting as a long shoal keel. To windward I would not do so except in the lightest of breezes if needed. There is a piece on the J22 I wrote for the JOA years ago on their website or I can forward it to you?
(laurie@lmilton.co.uk)
 
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VicS said:
I dont think anybody is suggesting it wont sail better with the keel down.

One thing for sure is that with it up its going to heel more, although its low ballast ratio is going to make it a tippy little boat I think even with the keel down.
Click to expand...

Its very stiff with the keel down...500lb and nearly 5 foot draft............
 
Camelia said:
Lifting keel boats are supposed to be sailed with the keel down all the time. They have the advantage of being able to lift the keel so that they:

  1. can moor in drying harbours
  2. can sail on very shallow water
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Not entirely true.
True lift-keel boats should not be sailed with the keel up - true lift-keelers being those with their ballast entirely in the keel.
Many drop-board boats wil actually go a lot faster off the wind with the board up (as any dinghy sailor will confirm).
I have sailed both and do not pontificate.
 
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