Hugh Welbourns's DSS 25

Monomaran on Hydroplaning foil.

The enquiry came from New-Zealand, quite a few years ago.
Loosing our nerves as the project developed, the client ended up building a (traditional?) Dick Newick's Tremolino.

 

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Thanks for the info, Yves! It is an intriguing idea...

 

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I found the Welbourn is building a cruising boat and posted it here somewhere. Enclosed is a picture. And a comment on cruising applications from an article about DSS on SA:

Martin Baum, Pantaenius: "I believe that this system could not only benefit the racing community but also the cruising world for several reasons. It helps to reduce the overall movement on a sailing yacht, can prevent capsizing and will thus make our sport more comfortable and safe. It might even reduce sea sickness and help to attract more newcomers to the sailing sport. A great invention."
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Found it here, Timothy: http://www.apolloduck.co.uk/display.phtml?aid=135241
Pix=JK 50 designed by Hugh Welbourn(click on images) :

 

Hugh Welbourn's 52, Neil Prydes "Hi Fi" won the Rolex China Sea race. Congratulations, Hugh! The boat doesn't use DSS but it was designed with the possibility of installing the foil and may be converted-or a new boat built. Pryde likes the DSS concept...

http://www.rhkyc.org.hk/chinasearace/results.htm

 

Congratulations,Hugh! One of the first examples of "foil assist" on a mono
hull keelboat shows her potential.....

Sailing Anarchy today:
"The new Welbourn DSS 25 doing its first race, the “Bay to Bay” in Queensland, Australia with plenty of sport boats and trailer sailors - 70 boats and over 2 days, so two races of about 30 miles. "Brace Brace Brace" came 1st both times in monohulls and knocked off most of the multis too.

There are plenty of seriously quick boats doing the event but even though the guys had only done a day’s testing since launch they got the gun both days. They reckon there is plenty more pace to come,.."

05/11/10

pictures from Sailing Anarchy,The Daily Sail and Ocean Navigator:

 

Dss 25

Just heard from Hugh Wellbourn. He sent a bunch of pictures but, unfortunately ,they are in a format I can't use.
He said he's gotten a lot of response and will be doing a new slightly larger ,
more powered up version for Swiss lakes...
This is a great technology and these pioneering efforts are very cool!
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UPDATE: figured the pictures out-all are from Hugh Wellbourn
Photo Credits: Vid Pic Pro.com/Julie Geldard-

 

JKyachts

More details on the cruising application of DSS, look at www.jkyachts.com, semi custom fast IRC friendly cruiser. Hull No.1 Due for launch second half of this year. Look up jkyachts.com on FB for the latest news

 

Dss 50

Just received this e-mail from James-which I appreciate very much:

"Thanks for the reply, we're very keen to let people know what we're doing.

We are building a VERY fast cruising boat that can be used in IRC, of course
fitted with DSS. Not only does the DSS (and design) make it one of the
fastest 50ft cruising boats available, the DSS foil makes the motion of the
boat feel like its at least 30% larger in any kind of sea, this is a huge
benefit in this cruising application. The entire concept of DSS is just as
applicable to cruising applications as to racing. The foil generates more
stability, with more stability you get more power, with more power you need
less sail area, with less sail area you have a lighter boat, a lighter boat
means....... do I need to continue???? Its a positive spiral that's enables
you to have a much more lightly equipped (sail area) boat without loss in
performance.

We have developed a thoroughly practical modern semi custom cruising yacht,
hull number one was designed to be sailed by a husband and wife team and
when required accommodate a few extra hands for racing. The JK 50 DSS, is
available in either raised deck saloon or flush deck models with a selection
of interiors.

The hull moulds are complete with hull number one due to leave the Ocean Tec
yard in July when the second hull should be well under way.
For more information please go to www.jkyachts.com , email info@jkyachts.com
, see JKyachts.com on Facebook or of course contact myself.

Regards
James Kemp


JKyachts.com
4 Higher Port View
Saltash – Cornwall – PL12 4BU – UK

t +447868025308
e james@projectandmarine.co.uk
w www.jkyachts.com

Click on image:

 

WOW. Its actually happening. How will it remain water tight? What drives it in and out? Or is it permanent? Does it have to stick out one side or another or can it pull all the way in? Otherwise docking will be a prob or someone will run over the foil with their tender.

 

with more stability you get more power, with more power you need
less sail area, with less sail area you have a lighter boat,

?????

 

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This foil system is the first production system designed to implement "foil assist" on monohulls. Not designed to fully lift the boat but a fully retractable system designed to increase righting moment, reduce wetted surface and improve handling, according to its inventor.

Here is the DSS site with some nifty animation:
http://dynamicstabilitysystems.com/#

 

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I think it's more like this: with more stability you get more power to carry sail,with more power to carry sail you can reduce the ballast normally required, with reduced ballast you have a lighter boat.
But a word of caution: this is a dynamic stability system: stability is enhanced as long as the boat is moving.

 

Brace, Brace, Brace : DSS 25

DSS 25 showing its speed :
http://www.sportsboats.hk/

guys still getting used to the boat-capsize in one race and this:
Race report - Autumn regatta Hong Kong
What a fantastic weekend! (90 boats)

But then it happened,Brace brace brace finally got the wind conditions they love and took off like arocket! It was impressive to see the guys holding on to the massive kiteand rounded the first mark well ahead of anyone else. They were extending theirlead and finished over five minutes ahead of the next boat who was FBW (only 14seconds ahead on corrected time).

 

Dss

A couple of pictures of a DSS foil on a T 30 in New Zealand-race results apparently so-so so far.


Brush with Sail Blog: July 2010
http://www.abrushwithsail.com/i-do-believe.html

The - 'I DO Believe What I'm Seeing!' - File
Wellington - Date-line Sunday 12 July 2009. It's mid-winter in New Zealand and sure, we go sailing in the winter, we have winter series racing in all yacht clubs in this tiny wee country down-under but there are times when it'd just too damn cold to even consider it. Today is one of those days, but at nine twenty, I get the call, 'If you want the pics, you'd better front. Pier B, at ten o'clock!'

It's blowing a really fresh no, call it, strong south-easterly, right off the Southern Ocean and the ambient is eight degrees C.But the call for sailing went out, not to race, but to show-off the Thompson 30 sport-boat Drinks Trolley and see if any of the much heralded claims made about Dynamic Stability Systems (DSS), stack up.

Is a group of sailors, such as this, called a 'gaggle?'

There is a fairly inauspicious start to the morning, as we wait - and wait - in the warm comfort of Kim and Julie's, Salthouse Corsair 36 Shariba, while five, or was it six, grown men, try in vain to put a second reef in the mainsail of Drinks Trolley!

Fifteen or twenty minutes later, it appeared that it had been decided to forget about the second reef and go sailing.

It was certainly going to be a revealing excercise, because Drinks Trolley would be carrying a lot more sail in the prevailing conditions than would otherwise be considered suitable, up-wind anyway. With one decent reef in, there was still a lot of sail area on show!

Fearing nothing, the lads bore away, hoisted the head-sail and off they went, with Shariba and her onlookers following at a fair pace.

Still plenty of sail-area with only one reef.
As fresh gusts pumped the breeze up from 25 to 30+? knots, there was obviously a lot of work on for the mainsheet hand, but it rapidly became apparent, that, not doubting his ability in the least, something else was greatly assisting the stability of this, slack bilged, over canvassed sports boat!

There is no doubt in my mind, that the DSS was working to stabilise Drinks Trolley.

Of the 35 photos of the boat, I shot during the next hour - and only when I thought it was carrying the force of a high-end puff of wind- only once was i able to shoot Drinks Trolley with an excessive heel. She stuck her bow in a large sea, partly kicked up by Shariba's
wake and slowed considerably, falling over as the mainsheet was dumped in a hurry, but bearing away and accelerating on the next wave, stood up straight and went for it!

The faster it went, the constantly straighter the yacht stood up! Having been a sceptic, I can now state categorically, that it was working for Drinks Trolley on reaches. The yacht was far too overcanvassed to sail competitively on the wind, without the second reef in the mainsail.

I might point out that it was a very rough day on Wellington Harbour and along with two other people chasing images and video footage, we experienced bumps, bruises and a hard time trying to keep the photographic equipment dry, with spray bursting right over Shariba, at times.

As other photographers will know, the sea never looks as tempestuous in image, as it does through the human eye.

After slowing in a big wave, a big dump of the mainsheet and 'Drinks Trolley' was up and away.

 

I would guess this will increase the chance of a capsize in real world conditions. Imagine being hit by a decent size beam sea in storm conditions. Most boats have at least some chance of sliding sideways when knocked down. Not this one. The foil will be pointing straight down when the boat is knocked down tripping the boat right over. The lighter keel will then add to the risk of a capsize. I believe BBB has capsized already. Not that this proves much but anyway.

I'm not dissing the whole concept. I actually like the idea overall. But you have to take some of the marketing hype with a grain of salt.