Sailing across the North Sea in a dinghy by Northbound

[Keith 66]

The LB ratio isnt really enough to exceed the hull speed limitation, her rowing boat inspired hull will make her fast & easily driven but the weight of the cruising gear she has to carry will make her unlikely to exceed hull speed to any high degree.
My current rowing boat is a stretched Cosine wherry, ostensibly similar but a much shallower hull, she is 17ft long & rows like a dream, she also has a 60sq ft balanced lugsail, with no dagger board. She can barely make to windward but off the wind on a reach or run is very quick, & will give a Laser a real run for its money in a breeze. To take her offshore like Northbounds boat would be suicide!
I think the hardest boat of all to design is a sail & oar boat that does both really well, most do one thing better than the other!
And yes it was John Seymour, long time since i read that book.

 

[dunedin]

Just wondering if the narrowness/beam might overcome the limitation of hull speed. ?

Any naval architect's out there ?

Narrow hull will lack form stability so difficult to generate much power under sail (unless large lump of lead 2m below waterline or twin trapezes) so generally slower than a boat which can generate more power and plane.

 

[Snowgoose-1]

Narrow hull will lack form stability so difficult to generate much power under sail (unless large lump of lead 2m below waterline or twin trapezes) so generally slower than a boat which can generate more power and plane.

I see
Like the old "lead mines" of old re AC.
I expect there is a reason why he picked such a narrow design. Hope he does a video about it.

 

[noelex]

The North Sea is the roughest water I have sailed in (although my wife feels the West Coast of Island in winter was worse). The trip from the Shetland Islands to Norway is only short and can be attempted within a favourable weather window, but still, it is a brave thing to do in the vessel featured.

Thanks for posting the video.

 

[boomerangben]

Just wondering if the narrowness/beam might overcome the limitation of hull speed. ?

Any naval architect's out there ?

Hull speed is not a hard barrier of course, just a sudden increase in power required for each increase in unit speed.

Where narrow vessels, or more specifically boats with a fine entry and streamlined stern, the size of bow and stern waves are smaller and therefore produce less resistance. I remember looking at the stern waves of a tradition fishing boat here in the outer Hebrides and marvelled at how little wake was being made, showing the importance of stern form.

Of course hull speed calculations are for smooth water. When you have a long passage with a following sea where the wave lengths are longer than the vessel and sufficiently steep, surfing becomes significant and of course the bow and stern waves are constantly being interfered with by wind waves. So down wind I can see why an average speed of greater than hull speed is not surprising. Going to windward would of course be slower, even with sufficient drive

 

[veshengro]

A short video that answers many of our questions about the boat, it's builder and the boat's equipment. Many aspects of the boat's build and lay out and the thinking behind them impress me. However...his solution for stability when carrying full sail in a stiff breeze being to hang out over the side on a Trapeze while crossing the Irish Sea or on a lively jaunt across to Norway, would terrify me.

 

[DownWest]

A short video that answers many of our questions about the boat, it's builder and the boat's equipment. Many aspects of the boat's build and lay out and the thinking behind them impress me. However...his solution for stability when carrying full sail in a stiff breeze being to hang out over the side on a Trapeze while crossing the Irish Sea or on a lively jaunt across to Norway, would terrify me.

Bonkers. So many things to go wrong...
I sail an unballasted 15ft Faering (no trapeze) and in choppy water have had some close ones. So, not being quite so agile... the new build can go 90° without significant water coming in. Little cabin and self draining cockpit. Plus, 200kg of lead in the keel, so I can relax a bit more if rough/windy.

 

[Keith 66]

Great video, I thought she was Whitehall inspired, for those interested in naval architecture its worth looking at the lines plan he shows early in the video, the classic Whitehall had considerable rise of floor midships which became a design characteristic of the type, this because of primary propulsion being rowing, The Whitehall i built was a Pete Culler design (Americas Yawlboat) & was a copy of two boats he built for the replica of the Schooner America, originally such boats would be fitted with a single spritsail of modest area.
Mine had a single spritsail about 60sq ft & because of her steep deadrise angle was initially very tippy putting her lee rail down easily. A disconcerting aspect was that when laid over sailing fast she would put about 5ft of lee side below the water & the bow wave would curve away from the hull in a long smooth wall, yet not come aboard.
Northbound has flattened the deadrise angle to increase form stability & raised & flattened the sheer to increase stability.
Im seriously impressed with what he has done with that boat & the thinking behind it.
As for the trapeze, he is a bloody hero!

 

[Snowgoose-1]

A short video that answers many of our questions about the boat, it's builder and the boat's equipment. Many aspects of the boat's build and lay out and the thinking behind them impress me. However...his solution for stability when carrying full sail in a stiff breeze being to hang out over the side on a Trapeze while crossing the Irish Sea or on a lively jaunt across to Norway, would terrify me.

Fascinating. Well found.
Not often you get both the cruising experiences plus design and build of the boat offshore.

Impressive speeds and a very interesting approach with the sail plan and handling.

The mind blowing bit for me is the capzing. He seems to be able accept it when it happens, and deal with it without too much fuss. Perhaps the narrow beam makes it easier to right the boat. How many times you can do it without becoming totally exhausted must require a high level of fitness.

 

[Keith 66]

A perhaps overlooked aspect of this type of hull form is ease of righting. My whitehall was a light open wooden boat with no bouyancy, capsized she would lay with the mast flat on the water, the hollow sharp waterlines meant little bouyancy below the waterline & she would self right with just a touch on the masthead. First time i saw this was on a film set filming a storm scene for a film at Pinewood studios, we had to tie an iron weight to her masthead to keep her from rolling upright. With decked in bouyancy in the ends self righting ability is increased.
The last rowing gig i designed & built of similar hull shape also does this, air tanks to deck level meant capsized she would ride on them & come up easily. Rnli lifeboats used this principle from the beginning to gain self righting ability.

 

[oldbloke]

The difficult trick is to have a boat that lies low in the water on her side so she is easily righted and doesn't turtle AND comes up with sufficiently little water in that she is stable and doesn't get swamped.

 

[DownWest]

The difficult trick is to have a boat that lies low in the water on her side so she is easily righted and doesn't turtle AND comes up with sufficiently little water in that she is stable and doesn't get swamped.

As earlier, my ''nearly finished' little cruiser will go over to 'mast in the water', with no water that comes in that won't drain out of the small foot well in the cockpit. The centerline hatches are well above the water if it does go over. Not that I expect that, but in the 'if,but' scenarios.

Local friend with a small open gaffer got it all wrong and capsized, three on board. The engine well and general set up meant they had no chance of self recovery. Had to call for help and were pulled off by an inter island ferry and helio. The 'gendearms de mer' recovered the boat and parked her on a mooring on one of the islands. Next day, we went over and bought her back. Stripped the new engine and cleaned out every bit. Insurance agreed that waiting for a service agent would have scrapped the engine, so coughed up for the bits.
Re,think. Increased bouancy and raised the surroundings of the engine well. Then pulled her over on the river to see. Managable water and quick bail out. Of course, it hasn't gone over since.. 10 yrs.