About landing crafts

it was a good one, just way off topic.

 

So, how is the snow? LOL

How is the project going?

I think you were right that other boats could be modified, just opening up the bow and reinforcing the bow and trim it out, but not too many suggestions that direction. And then it seems that without spending 6 figures, a smaller LC would just have to be built.

 

Sorry about the delay.

These two photos show the front end of a landing craft built by ATEC. The way I see it is this is a basic 4 panel vee hull boat design that has the addition of a ramp on the front end. Follow the keel line up to a point a little bit above the waterline. From this point the hinge line intersects, pull the side panels out to whatever width the ramp is, add the roughly triangular piece that fills in the area between the sides, ramp and bottom panel.

On this boat (and mine) the hinge line is above the waterline all the time, except for plowing into big waves. The ramp is not sealed in any way. On my boat I get as much water splashing in over the side from spray as comes in through the ramp edges. This boat has a sole that is above the waterline when unloaded, this makes for a self draining boat when moored.

On one particularly rough day I had the fun job of hauling a few people across the bay 8 miles with this boat (the ATEC boat). We were cruising along at probably 25mph when the winch holding the ramp up failed. The ramp dropped down into the water, the boat made a sudden stop and as the bow turned into a submarine the water came up to the middle of the boat. Once the forward motion stopped the water drained back out and we spent the next hour bobing around in the waves trying to get the ramp closed.

C.O.
http://whatsintheshop.blogspot.com/

 

Thanks CO, it looks like it has a very long bow to it. Some story too. I had already thought about using a couple bolts to keep the ramp up!

Maybe someone would know of an old boat that could be converted, at least the style of boat.

Don't know if that would be viable anyway as I'm stuck in the Ozarks, kinda far from everything except bass boats and pontoons. By the time I find something large enough I get into delivery issues and costs that make it unreasonable....I need to do any modifications here.

So the only alternative seems to build. Unless I find someone to assist me it looks like my limited skills will be keeping me in the flat bottom designs.

The flat bottom scows seem to work. Or a long sharpie. Regardless, it seems that long and narrow will have stability issues. To overcome this I thought that amas might be used. Making it a tri-

A sailing tri is not really what I'm after, just stability to reduce rocking. I can also see a deck over the akas could provide a small deck area. They could fold up or I could detach them for transport.

If the boat were say 30' with a 5'/6' beam, how would one figure out the length of the amas for stability purposes, the shortest possible that would make a significant contribution to that goal?

And, should amas be similar in design to the hull, I would think that if it were a scow, that the amas would look better if they were similar in design.

 

It's a little big for you, but here is what the real thing looks like.
http://kenai.craigslist.org/boa/2807960634.html

C.O.

 

LOL, if I put it in really hot water, would it shrink?

I'm sticking to just a bit larger than yours CO!

Trying to get a drawing of what I want and having some problems guessing where the rocker will start and end up, how far back and forward....I can just draw rocker, but it may not (probably won't be) right!

 

Folding ramps

What are the numbers that dictate the number of pieces in a landing ramp? I can see where a one-piece ramp stowed in seaworthy fashion, may block vision from the bridge. Are there any simple solutions or do we need a second hydraulic axis?

Ryland

 

Aren't SeaArk boats manufactured in Monticello, AR? They build landing crafts, as well as many other styles. They are pretty tough boats, IIRC.

 

Elevated helm.

 

Hey, sorry I'm late.....yes, Seaarks are made in Ar, but going through their site they have a commercial boat that was beefed up, but I could not find any LCs.

COR has a pretty good work boat there and maybe using scow plans, might get a decent motorsailor using leeboards which would be fun....I guess amas could go on if stability was an issue.

anything close to that?

 

Go here: http://www.seaark.com/site/start/marine_home.html
and click on "Transporter Series" in lower left-hand column...

 

Good point Ryland, probably a good idea to keep the ramp shorter, doubled over folding in two pieces, would a scew rod arrangement work there?

Yes VI they are made in AR, but by the time you get to a custom built large enough, same problems mentioned above $$$,$$$ and not fitted yet.

Got room to start something outside now, under cover....man it's hot!

 

My landing craft

I just got the trapezoidal bridge beams finish welded and fitted to the hulls. I think the landing ramp will be around 15 feet long and can be deployed, folded or extended to make more deck space. At that point, the vessel would be around 75 feet long. I'll try to post photos. I hope this isn't a thread hijack......if so, I will delete it. Please advise.

Ryland

 

Royland, I'd be interested in the ramp design as it may be adapted to a much smaller craft.

Your project is a one of a kind I'm sure and it surely deserves a special thread to itself, not saying the comments are not welcome, just that it would be great to have that project so it could be easily followed by everyone instead of hits in various threads. I'd like to participate in it myself.

As to much smaller crafts, I'd like to ask the possibilities of haveing outriggers on both sides, small OBs between the main hull and amas or pontoons set slightly forward so that the stern couldbe beached and laod from the rear. This cockpit area would serve double duty for gear or seating and having a forward cabin. Still in a garvey designed bow arrangement.

Sure wish I could load pics of drawings.....sorry!

 

Hi..Im have to haul about 2,500 Tons of construction materials (gravel, sand, steel rebars, etc) to COIBA island (pacific coast of Panama very famous worldwide for fishing in near by Hanibal Bank and is in the UNESCO WorldHeritage list).
I was looking to buy/lease a lcm8, but your design I think is awsome and I would be cheaper and more practical for me to build at my shop....Have you finished it? It would be great if you can post/email me more pictures at luiher@hotmail.com or luishernanriverawatson@gmail.com
What about the motors? are you planning to install outboards or inboards?...Take care and congrats on this project.

Luis