Dutch barges

Which are the key areas of compromise?

I'm not 'wedded' to barges per se. Its just that they have important attributes for me:
1. fit into the canals, and under bridges - not readily compromised!
2. space for live aboard amenities from length rather than beam, with benefit of lower engine power requirement and thus fuel economy.
3. LOA unlikely to exceed 24m due to licensing practicalities in France, and overall displacement being 'large but not monstrous'. In all likelihood can 'get by' with around 18m LOA
3. barges offer a lot of 'bang for the buck'
4. but, want it safe enough for coastal passages on East Coast or even to NZ provided care taken with weather windows, and vessel/systems not being too close to limits.
5. cruise 10 knots hopefully, enough reserve power for adverse wind/sea state or go a bit faster for times of need

 

We'd need to see your entire design brief before saying what should be compromised in that list. Do you want to sail I might have missed that bit?

So for a start
Min depth of water to navigate, maximum height clearance with everything folded down, maximum beam, and overall length. Have you thought of the cost and limits of haulout facilities you want to use, and local regulations and tickets required? That might limit maximum displacement.

Operating costs? Projected cost of bio diesel in 10 years ? Even a small simple sailing rig is a great fuel reduced .

You can have a bluff bow but wave resistance will dictate resistance. Looking at sheltered water resistance is no indication. If you want to motor at 10 knots into a force 6 with a bluff bow you'll need a big engine turning a big prop slowly (and getting close to 100 ft on the waterline) !

Would a catamaran be a better option? A big cat built in alloy might be worth considering ?

The other form that evolved for shallow water and coastal and even offshore passages is the Scow.

Off these forms only the Cat is a good efficient fast passagemaker.

From there on you can compromise with a monohull for whatever characteristics you desire. The designer will then have to play with the design spiral to get the stability, GZ, k, GM etc suitable for the area of operation.

You probably really need to sit down with a NA for an hour or two and nut out what your options are.

 

Thanks Mike - as always questions lead to more questions!

Yes, your right about time with an NA, but I'm wanting to get at least part way around another lap of the design spiral first, (Eg air draft as noted above) so that its efficient for both the NA and myself. I've tempered a lot of 'wishes' already, but know there's more to come. Will Allison's K5 concept/brief and design does have a lot of what I'm looking for, although I'd prefer 'commuter' or 'classic' styling than modern styling. And back to your earlier point, can I do it all in steel rather than ally for both cost and longevity/maintenance?

I'm aiming at a sailaway boat to finish fitout myself - that way I still get a project I enjoy but also get a finish date that isn't too far out. I'm also going to search some more for used boats that kinda fit the 'design brief' as lots of people have highlighted the cost and time benefit of that option. But it seems that there isn't a lot of long, skinny and low boats with good sea-keeping characteristics out there.

 

Bridge clearance / draft

Many of the category I canals in France are less than 2.2m deep. All the main routes are at least 1.8m deep, in theory (except the Garonne). The smaller canals around Burgandy are less - 1.4m for part of the Burgandy canal, less in the Nivernais canal (1.2m?), but you can go around these.

Even then, with a maximum gabarit, you will need to travel down the centre of the channel, and hope you don't meet a loaded cargo barge on a shallow stretch.

The main canals have 3.5m air draft, but again Burgandy area has lower air drafts (2.5m in Nivernais, 3.4m in Burgandy).

If you want to go directly from the Med. to the Atlantic, you'll need take the Midi Canal, which is not class I. It is shallower and has low bridges.

Some of the bridges are arched, and the air draft refers to the height st the centre! Check out Pont Marengo (http://en.wikipedia.org/wiki/Pont_Marengo) - it is 3.3m in the centre but only 2.6m at the sides.

You also need to bear in mind that the depth and air draft changes according to the season, especially on the canalised rivers.

 

Thanks Euro

It looks like the low bridges are the killer. In Brittany, either side of Rennes the draft is 1.2m and airdraft 2.5m, so I think that's not achievable for me and the Midi Canal is a bit worse. Although the guide says 3m airdraft for the canal, the Capestang bridge arch is effectively 2.4m high for a boat with 5m beam so Pont Marengo may not be the limiting one. These areas will need a different boat.....

 

A pilot house which breaks down is entirely possible, as suggested by Beebe in his book and as seen on some canal barges. You can see windshield hinges and the roof in three pieces (ease of handling) in this video.....http://www.youtube.com/watch?v=WJ_6hkFpyp8&feature=related

 

Nice video - just about ran out and got a plane ticket! Given its size I was surprised it can navigate Midi Canal given bridge arches. I guess the sole is quite a way below DWL, and walkways at sides of trunk cabin trims down beam at cabin top level to help as well.

 

I see a lot of those old converted "Luxemotor" barges around here (on the Moselle). They are perfect for the European canal system, but you would not want to go out to sea with one.

This couple just crossed the Irish sea in a Dutch barge: http://www.spallsatsea.com/ ! But they are using a newly built replica, RCD Cat B or C with a shallow V hull. (This interesting link was posted earlier by capt littlelegs - thanks!).

Even so, I'm not sure I would want to get caught in a storm at sea in one of these. It looks like one big wave over the folding wooden wheel house would knock it off the ship!