Barge to carry a single pick-up truck

[DogCavalry]

Considering how things are going with work, and what we are paying for delivery, there's a real business case to be made for a small landing craft barge.

SOR
Carry a full sized, fully loaded pickup, safely over moderate seas. Locale is east Coast of Vancouver island. Land on a beach, and deliver said truck to where it can drive away. Footprint of load is 7', 2.2 m wide. 20', 6m long
Max weight is 13000#, 6000kg. CofG of load is 3', 1m max height above deck. Generally lower.
Barge to be primary pushed, or side towed. Towed on a hawser if things go sideways.

No accomodations required on barge.

So the question is, I guess, dimensions of a barge that can have adequate stability. Naturally, as is the case here, I don't know the things that I don't know that I don't know. I'm sure I will be enlightened.

I'm aware that the project is a ways out. One of my lessons learned building Serenity is that I should have joined the forum a year earlier, and got things worked out. I joined a month before I started actual construction, and that cost me much time in indecision. If I had asked questions a year sooner, I could have moved much faster. So this time I'm asking a year ahead.

DC

 

[Blueknarr]

Good luck
Just an observation;
The CoG of an empty pickup may be a yard above the ground.
BUT
The CoG of the pickup 's load is often a yard or more above the bed.

 

[DogCavalry]

@Blueknarr , good observation. Since I'm packing the truck myself, I have some influence over load distribution, but a full load of insulation, for example, has tremendous volume, which will surely raise the net CoG.

 

[TANSL]

I have the basic project and complete construction plans for a 40' aluminum landing craft. It can be used as is or modified as needed. If it goes well for you, contact me via pm or email.

Edited: payload without engines and without fuel tanks: 6400 kg

 

[DogCavalry]

I have the basic project and complete construction plans for a 40' aluminum landing craft. It can be used as is or modified as needed. If it goes well for you, contact me via pm or email.

Pretty darn sweet. I'll have a good look. Presumably the SOR was clear enough, so this vessel could manage.

 

[Ad Hoc]

....
SOR
Carry a full sized, fully loaded pickup, safely over moderate seas. Locale is east Coast of Vancouver island. Land on a beach, and deliver said truck to where it can drive away. Footprint of load is 7', 2.2 m wide. 20', 6m long
Max weight is 13000#, 6000kg. CofG of load is 3', 1m max height above deck. Generally lower.
Barge to be primary pushed, or side towed. Towed on a hawser if things go sideways....

As always, depends upon the budget, as anything is possible, here is one we have done before:

This has various loading scenarios...the jeep shown is just one option.

Since if you wish a bit more, you can do more. But of course, everything on a boat, costs!
Hence, what is the budget...?

 

[DogCavalry]

Looking at your fine examples gentlemen, and a truckload that @bajansailor sent me, I think it should be 11'6", 3.5m beam, 33' 10m LOA. A socket aft that fits Serenity's bow for efficient pushing and control. Form, naturally is a sea sled. Simplified without non-tripping chines. Landing craft front gate and ramps. Comparable successful LC's regularly carry and deliver similar loads, so I think it should have adequate roll stability.

 

[fallguy]

My Uncle Jim went on tbe Berens River system fishing once upon 50 years ago and saw the Pikangikum tribe try to get a pickup over a rapids. They had a large log raft and drove the truck off below the rapids. Then they moved the raft through the rapids and parked it on one side of the lake above the rapids. The driver of the pickup did a good job of getting the truck up the hill, and my uncle watched the pickup disappear from site and a few seconds later heard a very loud splash.

Jim and his guide stopped fishing and went to look. The truck went over the raft and sank on the edge of the lake. The engine was probably toast, but my uncle said it was a pretty exciting day.

But the ship was budget friendly. Maybe up in BC you can even find a few floaters! Just kidding.

I think one trick is to make sure you have some good stake anchors to keep the ship from moving when offloading.

Otherwise, I don't have much to offer, but they still use rafts up in Alaska, based on a few tv shows I've seen.

 

[BlueBell]

I think it should have adequate roll stability.

Ah, designing by gut.
Ad Hoc won't like that... (neither do I...)

 

[TANSL]

Ah, designing by gut.

This is how a construction of this type and size can last several years and how when testing it in the water, a number of necessary modifications are detected to solve unforeseen problems, because intuition is not useful for designing anything.
But in this forum there are defenders of "construction without a design".It will be for something, I suppose.

 

[DogCavalry]

Well actually it's designing by the most time honored tradition in naval architecture: copying successful designs that have performed the same role in similar conditions. @BlueBell told me about delivering an F250 to a beach in a vessel called a sea truck. @TANSL and @Ad Hoc sent images of comparable vessels. @bajansailor sent me a dozen more, and when I mentioned @BlueBell 's sea truck experience he sent me a video of a Sea Truck 12 loading a 6 ton excavator, and a link to the specs on said vessel.

The Sea Truck 12 is, by coincidence, 12m long. However the last 3m are superstructure and engineering spaces and components. I don't need those. The cost of a barge is enough. An entire seaworthy vessel is more than I can bear at this time, so I excluded some of that length.

 

[BlueBell]

Well actually it's designing by the most time honored tradition in naval architecture: copying successful designs that have performed the same role in similar conditions.

Learning from others successes (and failures ) is sound, but it doesn't leave much room for innovation and advancement and can even lead to perpetual ill-design.
So we end up with similar commercial designs and stagnation in advancement.

I've designed and built enough boats to know that what may seem like an obvious design feature, can turn out to be completely counterintuitive in its effectiveness.
Humbling, shocking, confusing... educational.

I'm not advocating using any old design that looks to fit your SOR, but rather one that has been proven to meet your SOR.
There's a difference.

I delivered an AXOPAR 28 yesterday and marvelled at what a pleasure it was to operate through all the conditions I found myself in ( my immediate SOR ) over the two hour run attempting to make my expected time of arrival.
That's a proven design.
And gawd only knows how many hours went in to refining it.

 

[BlueBell]

So, to the locals, why don't we see any push barges around here.
I've never seen one and have travelled most of the west coast of Canada, except the Fraser River.
Have you ever seen one there @DogCavalry ?

 

[DogCavalry]

So, to the locals, why don't we see any push barges around here.
I've never seen one and have travelled most of the west coast of Canada, except the Fraser River.
Have you ever seen one there @DogCavalry ?

Never have.

 

[DogCavalry]

SOR states push, side tow, or pull.

Scantings for plywood epoxy glass build are the big question. Most such craft are welded aluminum, but I lack the skill. Welding aluminum is a non-trivial skill, that I could not reasonably acquire in a practical time frame. The opportunity cost would be greater than the value of the boat.