Stabilizers worth the dough?

My wife and I are considering a modified V hull boat, semi displacement something like an ocean Alexander 423 or 456. We are wondering how necessary or desirable stabilizers would be on such a hull. We are going to be cruising mainly in the ICW and hope to do the great loop. When doing the ICW we would expect to be able to go outside occasionally as weather permitted. We would also like to go back to the Bahamas.

We are former sailboat owners and are just wondering about the pros and cons to stabilizers and the relative worth of same.

I would appreciate hearing any comments from those with experience.

Thanks,

Gordon

Active stabilizers do work. Only you can decide if they are worth the money and space. For the tripe you describe I wouldn't bother just pick good weather and watch the wakes of other boats.

Worth the dough

Bayview,

Thank you for your response. I perhaps did not word my question as well as I might have. My real question has to do with how much ride improvement I will get out of stabilizers on a semi displacement hull.I have I have been on a Katie Krogen 48 and understand the need for stabilizers there. But I am unsure if ride improvement will be significant on a boat like an ocean Alexander drawing 4 feet and having hard Chines.

Thanks again for any and all insights.

Gordon

On our hard chined Hatteras 56, they made a huge difference. I have no idea how that might translate to the boat, and potential owner, in question here. Probably can only be answered by actual testing, which can be done if you can find a boat equipped with them. Do a sea trial on a day where you can spend some time in a beam sea and run the boat with and without them on.

If they are in your budget, get them. You will not regret it now or at resale.

Capt.Bill11 said:

If they are in your budget, get them. You will not regret it now or at resale.

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Better answer than mine.

Well for icw don't think you will need them much but when I got my 48 KK didn't trun them on till we were in the Gulf girlfriend said don't ever turn them off

Pure pleasure said:

Well for icw don't think you will need them much but when I got my 48 KK didn't trun them on till we were in the Gulf girlfriend said don't ever turn them off

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May not need, but sure will like the first few times you get waked; not to mention to crossing the several often choppy sounds that comprise big stretches of the ICW. If you have them, always use them!

I put stabilizers on my Grand Banks 47 which is a 4' draft, hard chine planing hull just like what you are contemplating. They made a huge difference. Worth every penny.

I can't wrap my head around putting stabilizers on a planing hull. We have one and it would seem to me that the drag would hurt performance or would tear them off after a while. At least based on the bigger ones we have seen on KKs and LRCs.

What am I missing?

All,

Thank you for all your answers. these have been the kinds of responses I have been looking for. People who have had them are glad they did. Again appreciate your responses anymore insights from anybody are and will be appreciated.

Gordon

Tom.B said:

I can't wrap my head around putting stabilizers on a planing hull. We have one and it would seem to me that the drag would hurt performance or would tear them off after a while. At least based on the bigger ones we have seen on KKs and LRCs.

What am I missing?

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Stabilizers slowed my grand banks by 1/4 to 1/2 kt at wide open throttle which was around 21kts. So negligible performance impact. There is some leeway in fin selection to be considered. You can use larger fins which will give more effective stabilization at lower speeds, but more drag at higher speeds. Or you can us smaller fins and get less drag, but also less effectiveness at slower speeds. We went with the largest fins we could because we wanted as much stabilization as we could get at or below hull speed. Even then, the high speed drag was negligible. And they are definitely not coming off.

Stabilizers on a planing hull are smaller and move less.

We have Wesmar hydraulic fins on our full displacement, hard chine timber hull. Cruise speed is 7.5 knots.

Fins this size begin to lose their effect at less than 4 knots with hydraulics driven from main engine.

No experience with stabilisers in previous boats, but now I wouldn't be without them for cruising in any sort of sloppy seas.

Anybody installed stabilization as a retrofit? How much did that cost? I have been looking at gyro stabilization but at $50k it's too rich for me.

I'd be interested on the cost from others.

I researched this one to death, and it's on the list, at some time, but initial cost for non-active was 40-50k installed for my boat. Add another 10k if active was needed. This is installed by a yard. Did not include anything else being done during Haulout.

Guess, I'll have to cruise another year to save the boat bucks.

I'm really trying hard to stay within the "paragraph" guidelines. Just saying!

We have 9 sf Wesmars on our 100,000 pound boat. At displacement speeds they work exceptionally well. My kids know if they are not engaged, even in relatively calm seas. On my shakedown cruise (from San Diego to La Paz), we were headed north up the Sea of Cortez into closely spaced 4' seas. Stabilizers don't do much (or anything, as far as I am concerned) to reduce pitch so the ride was a little uncomfortable. Since I had then not yet had any chance to put the stabilizers to the test, I was very apprehensive about having to turn to take those seas on the beam. To my surprise and delight, the rolled very little -- it was MUCH more comfortable than heading into the seas.

At planning speeds, my boat (most boats, in my experience) doesn't roll very much, so if you typically travel at planning speeds you probably won't appreciate the benefits of stabilizers as much as I do.

Fin size is important. A buddy with an OA of about the same size had the same stabilizers, but in the 6 square foot size. His are not nearly as effective.

Once you have them, you'll never go back. The impact on most planing boats is minimal. If that's really a concern, then you might try Side-power vector fins.

Stabilizer revolution - Side-Power

As to Gyro, we decided against for several reasons. First, the warm up time. Second, not so much a concern to us but might be to many others is the need to run the generator. Third is noise. Fourth is just old established technology vs. newer technology still being refined.

McGillicuddy said:

Anybody installed stabilization as a retrofit? How much did that cost? I have been looking at gyro stabilization but at $50k it's too rich for me.

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I had my Naiad's installed in Port Townsend about 3 years ago. Retrofit is a bit of a hassle and impacts on cost. Cost was a little over $60k all up, and the yard did all the work.

My fins are 7.5 sq ft., and they are very effective. I would not be without them and they are pretty much always on. They turn off (centre) below 4 kn from GPS input.

What are typical percentage roll reductions that you have experienced?

I had wesmar fins on my last boat and yes they made a difference but not enough to warrant what they would cost to fit nor maintain. I specifically looked for my next boat to not have them and found a 70ft hard shine motor yacht which cruises at 9 knots and have not even remotely missed the active stabilization.

The dropping of fins and level of maintenance is significant and adds to the cost of ownership to a point where for our use they are not needed.

The big factor is in how you use your boat and what weather you wish to boat in. With our cruising we are not crossing oceans and can plan to not have to boat in poor conditions so stabilization is not worth even remotely considering. Not even if free would i have them. Just not needed for our usage. But everyone is different and they can be awesome for others.

Inland they have little use , but do create a danger from knocking a hole in the vessel in a grounding.

For tiny runs like the Bahamas a SD boat will feel more stable at higher speeds , and get the transit over with quicker.

$30K to $45K would pay for lots of extra SD fuel burn.

I don't have any quantitative data on percentage roll reduction. There was a discussion on the forum some time back, comparing active fins to other alternatives but I could not find it. I seem to recall gyros around 80%, active fins quite a bit higher and paravanes very much lower.

Newer active fins have accelerometers in their control systems so the fin movement is large and early which gives the 'flat ride' experienced.

But its true that for older systems, some brands more than others, were high maintenance and somewhat problematic in other ways as well. Not sure of exact timing but I doubt that anyone with fins that are about 5 years old or newer, and have Naiad's or ABT's in particular, have had anything but joy from them.

Worth the dough? Question of whether my wife is coming or not and thus question of whether I have a boat or not.

makobuilders said:

What are typical percentage roll reductions that you have experienced?

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For us:

Probably 90-95% difference in roll with them on. In average seas you can put a glass down anywhere with them on. There's barely any roll at all.

Once seas build say 5 or 6ft, especially off the beam, they can't match the energy in the water, and she'll roll some, but nowhere like what it is without them.

When we were first researching moving from sail into a trawler, a friend told us we'd regret looking at boats without them. He was right. For us it's a must have.

Do people look to stabilization because they are prone to sea sickness? Just wondering... I can't come to terms with the cost, another service item on the boat, risk of banging a fin on something and compromising the hull compared to the benefit, unless one cannot go boating because of motion sickness then I'm sure they are welcome.

A fellow we know had these installed. Gyro Gale Stabilizers | Marine Stabilizers for Yachts
Cost was 1/3 less than Niads. They work at zero speed as well. They use compressed air, no hydraulics. I never heard of them before.

I was on a Hatteras LRC that had active stabilizers for a week of coastal and ICW cruising. When you turned them on and off you could definitely tell they were working.
I spent years cruising the same area on my boat without stabilizers and other than some big wakes didn't see the need. The guy who owned the Hatt was going from Tampa to Venezuela which means a thousand of miles of open water and beam seas. For him I think they were worth the cost.


For me in coastal and ICW cruising with lots of shallow spots I never considered them. If you have special needs such as prone to seasickness or balance problems the difference may then be between boating or not and they will be valuable.


Boats equipped with a schedule in coastal and ICW cruising seem most in need of active stabilizers. []


You can always add them later if you have problems.

makobuilders said:

What are typical percentage roll reductions that you have experienced?

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Depending on the boat and the stabilizer, normally the roll at rest is reduced by 40-75% and the roll at speed is reduced 70-95%. However, there are other factors beyond the measured distance such as the rate of roll. Ultimately, much like the weather, you end up with a combined "feels like". So the overall impact to passenger discomfort or reaction or sensation of roll at rest may be 60-90% and at speed may be 85-99%.

If you or your spouse or kids are having problems with seasickness, stabilizers can reduce that and even eliminate the problem in a very high percentage of cases. The numbers I showed above are for fins and vector fins. Gyro stabilizers will be on the upper end of those rangers as well, in the range of 90-95%.

hmason said:

A fellow we know had these installed. Gyro Gale Stabilizers | Marine Stabilizers for Yachts
Cost was 1/3 less than Niads. They work at zero speed as well. They use compressed air, no hydraulics. I never heard of them before.

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Are you sure they work at zero speed? The reason I ask is that on their website, they have charts showing the roll reduction on a Hatteras LRC and then to the right of that the percentage reduction at various speeds. That chart shows 0% reduction at 0 knots, about 55% reduction at 2 knots, and 87% or so at 4 knots and above.