Car Ferry

[kajatar]

Hi guys, I'm new here and have a question for you all. I want to build a car ferry, and no, I'm not ambitious, I only want it to carry 1 car. What I am looking at is a loading ramp at the front, wheelhouse at the back, outboard powered. Total vehicle weight 2800kg, 4-6 adults @ an average of 100kg each, and general fittings associated with a powerboat (anchors, fuel, batteries etc). It will be constructed of plywood on timber frames. The question is what size (length, beam, depth (not the same as draught) etc) will it need to be. I will be operated in smooth water with the occasional swell of about 2-3 feet.

 

[Ad Hoc]

Being such a small boat...you would be wise to use a catamaran hull form, ostensibly for stability and it also gives you a nice large deck space.

 

[kajatar]

Thanks for your advise but, and while I am not doubting you word I was thinking of a flat bottomed barge 7.6mts X 3.6mts. So would a flat bottomed hull that size not have a greater load carrying capacity than catamaran hull?

 

[Mr Efficiency]

What is the weight and type of "car" ?

 

[JSL]

Check out Specmar, they have a good selection of landing craft designs

 

[PAR]

I see a minimum of a 6 ton craft, so your flat bottomed boat ~25'x12' will get it done with lots of room to spare, volume wise, though length might be tight, given a ramp and aft wheelhouse (depends on elbow room desired). A craft of these dimensions would draw roughly 6" (150 mm) at 4 tons. There are several considerations to something like this to insure it's safe, practical and reasonably economical to operate and I don't think a novice designed vessel will address most of these concerns. Just developing a water tight ramp that can handle a 3 ton car, not buckle, distort and be light enough to be practical, etc. will be challenge enough.

 

[kajatar]

Check out Specmar, they have a good selection of landing craft designs

I did, and they do. They are exactly what I am looking for but I wont be needing a V bottom.

 

[kajatar]

I see a minimum of a 6 ton craft, so your flat bottomed boat ~25'x12' will get it done with lots of room to spare, volume wise, though length might be tight, given a ramp and aft wheelhouse (depends on elbow room desired). A craft of these dimensions would draw roughly 6" (150 mm) at 4 tons. There are several considerations to something like this to insure it's safe, practical and reasonably economical to operate and I don't think a novice designed vessel will address most of these concerns. Just developing a water tight ramp that can handle a 3 ton car, not buckle, distort and be light enough to be practical, etc. will be challenge enough.

Thank you very much. That was exactly the advice I was looking for. I think I could safely bring the beam down to 9-10ft and still be safe. Indecently, the car I'm putting on it a Range Rover and it doesn't weigh 3000kg, it only weights 2250kg. I'm just giving myself a safety margin.

 

[rwatson]

I dont know if some previous threads will have any value for you like

http://www.boatdesign.net/forums/boat-design/parallel-concepts-vehicle-powered-barges-50283.html

 

[kajatar]

I dont know if some previous threads will have any value for you like

http://www.boatdesign.net/forums/boat-design/parallel-concepts-vehicle-powered-barges-50283.html

I'll check it out, thanks for the info.

 

[myark]

Hi guys, I'm new here and have a question for you all. I want to build a car ferry, and no, I'm not ambitious, I only want it to carry 1 car. What I am looking at is a loading ramp at the front, wheelhouse at the back, outboard powered. Total vehicle weight 2800kg, 4-6 adults @ an average of 100kg each, and general fittings associated with a powerboat (anchors, fuel, batteries etc). It will be constructed of plywood on timber frames. The question is what size (length, beam, depth (not the same as draught) etc) will it need to be. I will be operated in smooth water with the occasional swell of about 2-3 feet.

Hi Kajatar

This is of the early proto type Myark folding trailer barge that is 7.2 X 3.6 X .400 with the width folded is .800 wide and weighs 800kg, built in trailer included so you can have an idea on how much that area will float.
It has a 5 ton Jayco camper van on top which you can see a movie I made in a remote New Zealand lake with my dog. http://www.youtube.com/watch?v=DDfSuAtiVkQ
The other picture shows a Jayco pop up camper planning with two 15hp four stroke motors.
You do not always need to go wide as I have had no problems to float cars with a 2.m wide barge such as on my other models called trailer barges that have removable torsion suspension.
These are great for towing and you can take the trailer and car with you.
Pictured with two 25 hp outboards planning.

 

[myark]

This is an example of a 2.m wide Myark trailer barge with small car on top.
All that needs to be done is raise the sides to suit the extra load like the Myark trailer barge with the film company props that I hired out to the USA company that filmed Hercules.
These barge types sold well to the oyster and mussel farmers as they could load up at sea with marine product and did not have to double handle into a waiting trailer or truck.