10M Thai Long Tail

[brian eiland]

Here's a couple of photos I found.

Looking for them brought back memories of Thailand. I like this country, its food, and its very gracious people. I was just over there last Aug picking up a scale model of my 65 cat design.

I need to return soon and idle down my frustrations with this Bush administration. Helping the Thai people recover from the Tsunami should be a lot more rewarding than trying to effect this wayward administration and congress (I live in Washington DC at the moment)

[Mikey]

I don't, like the Thais , care about regulations too much IF the end result is good and it benefits the community. But you are of course correct that some enhancements probably could be made.

But I would be very cautious, remember what happened to the very sea worthy fishing boats working the north Atlantic? Despite being bigger than the older ones, they became less sea worthy. Not to mention what this forum mainly is about and Fastnet 79. I would not make the FRP longtail boats lighter than their wooden equivalent That would increase accelerations and make the boat more difficult to work from, sea kindliness, the forgotten aspect

I have not seen any longtails being made, but I have seen the bigger "real" fishing boats. All that sawing and matching of the planks, very time consuming, very manual and requires a lot of skill. Yes, to add some efficiency to this process would not be a bad idea...

I think it is a very good idea indeed to use FRP, it is also cheap if it is locally produced. Would be cheaper too, wouldn't it? What is the price for locally produced, say 24 oz woven roving or 2415 stitch mat?

Mikey

[tom kane]

Many thanks to all for interesting images and information,I hope there is more where that came from.I am very interested in propulsion system in relation to where the propeller is run for efficiency.The pressure waves formed by the hull would give the props something to push against.May vidios I have seen show them moving very fast.I have some images showing big V8 powered craft.

[Mikey]

Tom,
The V8 powered craft you have seen are surely from Vietnam. Saigon (Ho Che Minh) still has them, remnants from the Vietnam war I suppose. Thailand does not have them.

They are extremely fast! 30+ knots easily for some of them.

The high placement of the engine is not really a problem for the Thai fishing boat longtails, at least I did not feel it was, but that would mainly be because the enormously heavy flywheel that the horisontal diesels have. Snappy is not the word...

The engine is truly multi-purpose. The same engine can be the on the "tractor like" vehicle Thais use for the rice fields, and it is also used to drive water pumps, and why not on the "tractor like again" vehicle that they use to drive to the rice fields on. "Tractor like...", well I don't know how to describe them. I will try to find some pics.

I have seen Toyota 4 cylinder car engines being used on the "car engine longtails", I don't know for sure but think that this is the most common engine used on them. Since they have much more power and react much faster to the throttle, I can surely believe a soft hand would be good if you don't want to swim.

Mikey

[S.E.A.]

Hi Everyone

Sorry for not following the posts as much as I could but just spent the last week in Phuket looking for suitable shipyards etc and seeing whats going on to help the Fishermen.

The build specs of the 10M LongTail are printed below but still waiting for final details of the first one built as well as sea trial report etc

Length : 10.00 metres
Beam : 2.15 metres
Depth : 0.80 metres
Draught : 0.20 metres
Engine : 10 HP Air Cool. OR
50 HP Water Cool
Propeller : 2 Blade Fixed
Light ship : 1 ton
Displacement : 2 tons ( full load )

As soon as I have some more info Ill post here.

[Alik]

Are these LOA and BMAX or LWL and BWL? I try to generate stability curve for that boat, so maximum GZ tends to be only 0.25...0.30m. Also, downflooding angle is somewhat 30 deg. Am I right?

[S.E.A.]

Hi Alik

As mentioned before I am just a conduit for the information but where can will reply to your questions. Have passed on your questions/ thoughts to the designer and will reply soonest. In the meantime have just been informed that sea trials are commencing on the first completed 10M LongTail so I will update shortly with results and pictures

[Alik]

Thanks, S.E.A.
I am seriousely concerned about their stability/safety.

[S.E.A.]

Pictures taken of the Long Tail Test in Bangkok

[S.E.A.]

50hp Engine (water cooled) being mounted, checked before trails

[Alik]

Looks nice!
This open boat requires emergency flotation elements, because now it is FRP, not wood.

[tom kane]

Printed great images thanks,love that propulsion,it must make some engineers crazy.

[tom kane]

Perhaps the propulsion shown in images would be a good inovation.Many ways of building and installing.Low maintenance cheap to build.Not a lot different to the present set up.Motor does not pivot,just the shaft.A pivoting drive allows shallow water operation and kicks up if obstruction struck.Can have a shroud around prop.Many advantages.

[Frosty]

Normally used is the ubiquoutous Yanmar TS 70. Or 80 90- single diesel They were primarily for agricultral instalations. These engine at 7 -8-9hp are expected to--and do--- run alone unattended for days in irrigation systems. They are stripped of un-neccessries and bolted to a frame when used as a long tail engine. The reduction gear at a guess is at least 3-1 more like 4. They have a funnel arrangment just aft of the prop that picks up water and pushes it through the block and over the side. Thats it. The liner and piston is 800 Baht as I bought one once,--42 baht to the us dollar. The liner is pushed home with the cylinder head and stock bolts, the crank has ball bearings on outers and can be removed from the side. The big end shell for the con rod can be replaced through a plate at the rear without even draining the oil. These engines can be overhauled in the forest in about 2 hours. Parts are very un-believably cheap.

[tom kane]

We have one long tail boat in Zew Zealand,not sure which area it`s from.I have always been interested.The image shows another attempt at propulsion,I do not know where they were mainly used.