Hull development for Journeyman 60
The Journeyman 60 is a project conceived and nursed by Jesper Weissglas. Mr Weissglas is a man of , as it seems, unlimited talents. Having once run a boat professionally, charter sailing to Greenland and taking part in an expedition across the continent, he was subsequently a little restless after a highly successful career in IT in Stockholm.
When Jesper Weissglas decided he needed a new boat, his demands were special and nothing on the market filled his requirements. The fact that he had never designed a boat before did not really deter him from designing his own. He started a 5-year process of design and engineering which went through 9 iterations. After having more or less completed these 9 different designs, the Journeyman was born.
Jesper Weissglas' design # 9 |
For Jesper Weissglas, taking up yacht design obviously had nothing to do with romantic fiddling with dream boats which would never hit the water. He had a goal.
I liked this project from the start, as much as I admired the man behind it, for their honest open-minded sincerity. Both Jesper’s and Journeyman’s.
Faster, easier motion, drier, better steering, directionally stable
Jesper Weissglas’ hull for the Journeyman was a decent, ordinary, fast hull. Rather slender, but of very modern proportions. Blunt stem, wide stern, easy lines.
But over the past decade, we had been testing and tweaking the hull volumes, under water and above water, to make boats go faster offshore, with an easier motion and drier decks. In addition, the same changes made our designs easier on the helm and more directionally stable.
These new designs had been evaluated in a study at Chalmers University of Technology and, surprisingly, apart from having better handling and an easier motion, VMG was improved by approx. 4%. These results were also verified at SSPA, the test tank facility in Göteborg.
I cannot remember now whether Jesper Weissglas had heard about these studies when he turned to us to confirm that the hull shape would work. But I said that Journeyman could be turned into a better boat, and that the difference would be significant. I guess he was thrilled by this option but he looked at me in disbelief. And replied that we were going to be challenged in such case and that he was going to perform a CFD study of our hull design alongside his own. This trial would have to confirm what I was trying to say.
The re-design
In the case of Journeyman, Jesper Weissglas’ basic design was set.
A fine entry, able to slice through waves without losing speed |
However, the waterlines were made sharper forward, for slicing easily through 1-2 m high seas. The decks, on the other hand, were made wider forward, for a dry, buoyant hull.
The boat was made more buoyant aft which meant the keel could move aft. In the screen dump below, the first picture shows the original keel position. We suggested three different keel concepts. All took advantage of the buoyancy aft, moving the keel bulb aft by more than a metre.
Keel configurations, original position at upper left |
· One did not have a protruding bulb, to avoid getting snared in weed and fishing lines
· One had the keel blade at an angle aft, to avoid the keel casing ending up in the pilot house.
· The third one was based on the original Torpedo-shaped keel. This was the keel chosen, for mechanical reasons, as it was the only configuration that would put even loads on the keel hoisting mechanism and the keel guides inside the casing.
Whichever keel concept would have been chosen, it would move the keel area aft, the boat would track better, allowing the helmsman or autopilot to rest. Doing so, the sail plan could move aft as well without putting too much strain on the rudder. This also meant her ‘J’ could be increased a little, her boom could be a little longer, her mast could be made a little lower. Thus, her sail area could be a little bigger, without making her heel more.
CFD result
Journeyman, wake pattern at 8 knots |
As it turned out, the design suggested by us showed much lower drag. I cannot give exact figures, besides, this would perhaps be misleading as the tests were conducted without the usual number of different heel and leeway angles.
Combined with the expected improvements in steering, motion in a seaway and slightly increased sail area, the overall gains seemed irresistible. Jesper Weissglas took a deep breath and started working on design iteration # 10 – which meant a complete re-design.
As the interior volumes had changed, the keel position had moved aft changing the interior layout and the mast as well to some extent. This meant the interior layout, the position of water ballast tanks and the structural drawings had to be changed. In fact, these changes made a number of improvements possible. At this stage, our role was merely to act as discussion partners and help with advice.
Journeyman # 10
So how did Journeyman turn out in her final configuration?
I think, just as intended. Only a little better.
She is just the purposeful, benevolent, fast expedition yacht she was intended to be. And she is utterly comfortable at sea.
She is just the purposeful, benevolent, fast expedition yacht she was intended to be. And she is utterly comfortable at sea.
On 18 July Jesper wrote:
Well, just nu sitter jag vid navbordet och njuter av en sträckbog i
solnedgången mitt mellan Fårö och Västervik, det har blåst på så sjön är
rätt gropig men nu har vi 8 m/s vind, 29° AWA och full ballast i lovart,
det tutar på i 8-8.5 knop med 17° lutning och inte ett vågstamp så långt
jag kan minnas :-) Rorsman behöver peta till rodren lite sådär var 10e
minut eller nått, annars styr hon sig själv mest hela tiden.
Maken till seglingskomfort får man leta efter. Det tackar vi för.
/j
solnedgången mitt mellan Fårö och Västervik, det har blåst på så sjön är
rätt gropig men nu har vi 8 m/s vind, 29° AWA och full ballast i lovart,
det tutar på i 8-8.5 knop med 17° lutning och inte ett vågstamp så långt
jag kan minnas :-) Rorsman behöver peta till rodren lite sådär var 10e
minut eller nått, annars styr hon sig själv mest hela tiden.
Maken till seglingskomfort får man leta efter. Det tackar vi för.
/j
In translation:
Well, I am sitting at the nav table enjoying a reach into the sunset, halfway between Fårö and Västervik. After a windy day the sea is rather choppy but the wind has now come down to 16 knots, we are rushing along at 29° apparent, full ballast to windward, 8-8.5 knots and 17° heel. Not a single slamming for as far as I can remember :-) The helmsman needs to touch the helm every 10 minutes or so, other than that she steers herself.
Sailing comfort like this must be rare indeed. Sending our thanks.
/j
The Journeyman was finished and tested during 2010 and 2011, the official christening party took place in September 2011 followed by a huge crowd of friends and admirers. Renowned racing yachtswoman Pia L'Obry was her godmother.
Admirers |
Pia L'Obry |
A fanfare composed for Journeyman. Jesper to the left |
Two days later, Journeyman left for a world cruise. You can follow her on this site.
Journeyman has no problems carrying a full main and a small staysail in a blow. Steering is never an issue. |
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