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[MikeA]

Not so long back i started a thread about losing my boat on the local lake and how it took over 2 days to get it back. To jog your memories or if you are unfamiliar heres the link:

http://www.modelboatmayhem.co.uk/forum/index.php?topic=33096.0

I would like to share with you my solution to the problems i face just in case things dont go to plan and i need a recovery. I have now a backup in progress and just wondered what you pros thought. The Criterias which i faced were:

1, must be quick to set up, quick to launch and quick to the stranded boat, before it gets into an even worse situation.
2, must be wide enough to fit round all the boats that i have
3, must be able to push and control the boats i have
4, must be easy to transport on the bus
5, must be cheap!

Here is my solution:





One of the limitations i have is transport so buying a dinghy is out of the question and building large boats is a problem too so all my boats are relatively small, no more than 2ft long. I had to design a fast tug type vessel which can fit around my boats but this would make it over a ft wide which is no good because if its that big i cant take my main boats! The sponsons if thats the right word fold up for transport changing it from 12 inches wide to a more managable 7 inches. It will have a single 540 motor in it to a 35mm prop. with 7.2 nimh split into 2 packs of 3 in either hull.

It seems like a long winded way to get your boats back just in case, but going on the water is out of the question. Theres sometimes people on jet skis but their at the other end of the lake a mile an 1/4 walk away and even if i did make the walk i will lose sight of my boat. I think it should work anyway.

[marinemole]

Very ingenious. Would be interested to see photographs and/or video of a trial rescue.

Andy

[MikeA]

thanks for the compliments Its only the bare hull at the minute, theres no mechanicals ill try and get a vid or pics posted of it working when its finished.

[john s 2]

Instead of making a whole boat,why not make a frame to fit around an existing boat? 22mm plumbers pipe and the judicous use of bends 90* and 45* plus 3 way elbows and end stops.Can be fitted together to make a frame to go over and around a suitable hull.Use solvent weld glue when finished to hold together.This can be a cost effective alternative to a dedicated rescue boat.John.

[malcolmfrary]

Dont forget the long piece of string.  Sometimes boats get stuck because of something in the water that affects not only the original stuck boat, but also the rescuer, leaving two stuck boats.  The piece of sting is a low tech, but very reliable, method of retrieval.

[MikeA]

Instead of making a whole boat,why not make a frame to fit around an existing boat? 22mm plumbers pipe and the judicous use of bends 90* and 45* plus 3 way elbows and end stops.Can be fitted together to make a frame to go over and around a suitable hull.Use solvent weld glue when finished to hold together.This can be a cost effective alternative to a dedicated rescue boat.John.

i had thought of some simple solutions, but this seemed to be the best answer. either way i need a seperate radio to one in the normal boats which is till an expense. i also dont have a boat suitable to push other than my trawler and its too small, i would still have to build a larger boat and if i built a larger tug or trawler it would get broken in transport. also the frame would have to break down to fit into a rucksack which then would have to fit a trawler in and then the speed boat. I thought about putting a fork on the front of my other boats but then it would still need to fold and need some kind of floation to stop it from lifting the props out of the water.

[MikeA]

Dont forget the long piece of string.  Sometimes boats get stuck because of something in the water that affects not only the original stuck boat, but also the rescuer, leaving two stuck boats.  The piece of sting is a low tech, but very reliable, method of retrieval.

i hadnt thought of that ill take that on board 

[john s 2]

Good luck Mike.Please let us all know how it goes as retreiving boats is something most of us have had to do.Its not so bad when your in a crowd  ,but on your own its much harder.John.

[Netleyned]

If you have a 2.4 GHz four channel radio, you can just get another receiver and use the other two stick axes to run 'Rescue One'
Its also worth having a reel of fishing line to attach to the rescue craft to go out and circle round the casualty and bring it shoreside
by catching around the stern gear.
One word of warning though, don't run ahead or astern on the casualty if using this method as it tends to reel you in!

Ned

[barriew]

What you are building will certainly work - provided you are not stuck in weed when there is  danger of getting the rescue boat stuck also. In the March MMI there was a design for a rescue boat powered by a ducted fan. I thought that was quite a good idea.

 Barrie

[wullie/mk2]

I have thought long and hard about this problem myself being a lone sailor much of the time. My solution is as follows;
First I built a cheap and cheerful airboat, doesn't need to be pretty, or fast, and no prop to worry about. It's only purpose in life is to get a line out to the stricken vessel.
The line is a fishing monofilament that will not sink. A fixed spool fishing reel attached to a piece of broomhandle or whatever is the method of retrieval. The line is firmly tied to the airboat. That is the equipment you need. The method of use, which I must admit is, as yet, untried is as follows.
The rescue boat takes the line out to, and past, the boat to be recovered, by a couple of metres. Then hard left or right to form a loop around the boat to be saved continuing round to "lasoo" the boat. It will probably snag in one way or another. Reel it in. My reasoning behind this method was that if it is a yacht being rescued it could be at the mercy of the wind and therefore not so easy to simply push back to shore. Hope this helps somebody. Apologies for repeating a previous post, but I wrote this a few hours ago and didn't get to post it.

[MikeA]

well in my perticular situation its for the retreival of my powerboat. So far i have been very careful with but other day i flipped it again i dont know why it happened just went over some ripples on the lake a gust of wind over it went. Its not the first time its happened either, the other time i was lucky as it flipped close to the bank and drited towards me but on friday i decided to take a risk and send it way out in the middle of the lake, it was at least 100ft away from the bank. I contemplated about it a minute. I was considering abondoning it, then i tried to push it back with my trawler. My trawler runs on the same rc gear as my powerboat and so when i pushed forward on my throttle the trawler went forward but the powerboat was switched on aswell still and it was screaming upside down, cos it was also getting the forward command. I was trying my best with the little trawler to push the power boat back but i could barely see it. Anyway luckyly a guy with a bait boat pushed mine back thanks to him. Its been on my mind to build a recovery boat but i was putting it off for a pt boat build, not now though.

Weeds are rarely a problem (touch wood) because i sail in a massive open space but the huge gusts of wind are a real problem so i have to overkill with power on all my boats. The recovery boat will have to be no different.

[malcolmfrary]

The great thing about running a line out is that the rescue boat only needs the power to get out there and circle - you provide the horsepower on the way back.  You don't need to be as good a shot at distance, either.  Using a rod and nice big reel is probably a good idea - you can get a lot of line on the reel, and it provides somewhere tidy to put the line when you pull it in.

[MikeA]

its seems like a good simple idea. Im not entirely sure what the line would snag on my boat though, its very low profile. Ill carry on with the way its going atm, as the ability to steer the boat back is pretty important. The perimeter on the lake is about 1.5 miles 1.3 miles of that perimeter is not accessible to the waters edge by fields of reeds and bushes. 

[malcolmfrary]

If its a fast boat liable to flip, there will be a prop and rudder sticking up.  If the line slides under, there is often an aerial tube or similar to snag.  If its still the right end up, much the same applies.
With your design of capture, fixing the line to the front of the boat would enable you to dock the casualty in its arms, pulling in would keep the rescue boat plus its catch facing you.  Only problem then is ensuring that the rescue boat doesn't run over and tangle its own string.

[MikeA]

I suppose there are many methods available for recovery. From my experience of the lake i sail at a lot of simple methods have been ruled out though. Maybe my solution is bit OTT but id rather be OTT than insufficient. using string seems like a good fall back but whats the point in pulling the boat back when it has the ability to push it back? the powertrain for it will cost me beans, the radio too. Btw ive painted it white, i had loads of it left and itl save me some money. I dont like the look of it though i might paint it orange later.

 i keep saying on here it was about 90ft away from the bank, it just goes to show my bad estimation of distance. Using google earth it was actually more like 370 ft lol

[MikeA]

Its been a while since i posted any progress of my rescue boat build and thought id show you the finished article (I hope). The reason i say that is because ive had to endure an imense amount of faffing about with it and now i can hand on heart say its the ugliest creation ive ever devised. Ive takin it out now for 3 test runs, although my new TXRX hasnt turned up yet ive been able to trial it with the one i have.

 Trying to make the boat foldable I put all my design efforts into making it so, only i forgot about the basics of boat construction. The flat front of the middle hull and the booms for the outriggers acted like a giant brake and in conjuction with the steep angled propeller on the first run the boat plowed through the water in such a way it was lifting the transom out of the water and exposing the propeller. Im afraid i have no pictures of the sea trials as i was on my tod and cant operate a camera and sail a boat at the same time. I have however pics of my solutions.

First modification was to put a more pointy front on to stop the water flooding the deck, and sum sections of the booms cut out to shop them dragging in the water.



With the middle hull only being 8 inches long the space inside was very cramped especially with a 540 motor. I used an MMB propshaft and cut it down to 2inches with 35mm prop on the end. The prop angle is very steep but not causing any issues.





The rear on the boat showing the rudder, the notches cut out the rear booms and some tabs which allow the water to flow over the top of the booms rather than pile into them.



I fitted a push button on off switch on the top for a fast launch. its been water proofed with a balloon. The strategically placed sponge    saves some of my paint work when im trying to scoop up boats. The batteries are stored permanently in both outriggers. 2 banks of 3 subC cells are joined togeather by the black power wires entering the middle hull.

Ill try and get a video showing it rescueing something at a later date.

[MikeA]

forgot to add a last pic: