My HENG LONG 25" tug rolled in a crosswind & sank on its maiden last summer. Fortunately I was sailing with several members of MMM (Metro Marine Modellers in Toronto) who had experience with such events.

The hulk was in abt 6' of clear water very close to the vertical walls of the launch ramps. They grabbed the closest light aluminum "J" poles from lifesaving stations & manhandled her ashore. Fortunately she weighed considerably less submerged as she displaced several pounds of water.

The design uses a waterballast chamber open to the sea thru grilles in the bottom of the hull; it floods in the 30sec right after launch. For this season I have removed the fire pump & sealed the flood grilles with ShoeGoo.

Ballast is now a 6V 4AHr SLA (I cut off the lid of the ballast tank using my Dremel, the battery fits perfectly, almost filling the former ballast tank) & some lead shot rather than a few cu. in. of water. I am also adding a bulb keel, sailboat-style.

Battery & all electronics replaced.

Hi RN
You are quite right to identify the likely friction points. I had to go through the process myself.

Initially I tried a fishing float but this did not have sufficient buoyancy. After drinking (most of) a bottle of bubbly the answer came to me - use the cork. It was easily fashioned with sandpaper whilst mounted in the chuck of a drill. A flotation test was carried out along with a sensitive weigh scale to determine the 'pull' it would have on a line.

It took two or three attempts with the drum to get it running easily, and the size of the eyes on the mast that hold the float had to be increased to allow the buoy to freely float free.

I have not tried sinking the yacht to see whether it will all work as and when required so I just hope the buoy will not be required.

After a number of sailings I managed to reduce water intake to a minimum, maybe just 20cc, even after many minutes of sailing with the lee rail completely under water. This is not even sufficient to reach the electrics, let alone cause any trouble or possible sinking. The volume of water intake required to sink the boat is around 2000cc, so I don't anticipate sinking any time soon ! 😉

Hi flaxby,
"At deck level the line runs to a bobbin (or drum)."
Your solution certainly looks good in the photos but the one factor that's been bugging me since my first tentative 'thunks' on the subject has been friction! How to ensure that the whole shebang is a friction free as possible and that it actually releases in case of a 'disastrickle'!😮😭 Have you tested your setup for free running?
Your solution appears to have three potential friction points-
The loops that both tether and spike pass through,
The 90° turn through the ring at the mast foot,
The cable drum; bearings, potential line tangling.
Do you know if your bubbly cork has enough buoyancy to overcome all this?

For my sub, type 1A U25, I was thinking in terms of using the aft torpedo loading hatch with the float and the flat-coiled tether in a compartment within the flooded hull section.
Flip the hatch and away she goes. It's the flipping that's the tricky bit🙄
The float could be a Minion body😁 e.g. a yellow Surprise Egg case.
Cheers, Doug😎

Having seen my friend's schooner sink I needed no further encouragement before making the buoy pictured below.
Having espoused the need of such a 'simple extra' I am all the more surprised that fellow LBMBC members have not adopted it. !!😉

flaxbybuck,
I love the idea!
I nearly lost my Robbe Paula III last year in our pond.
A float disguised as a buoy, and attached to a bobbin is ingenious.
I will have to try adding a feature something like yours.
Thanks for the great idea.
Dave B

I indeed encouraged Flaxbybuck to add such a device to his newly- built schooner. This was after my scale motor sailer "Lockdown Dream" actually sank on another club's lake while leading a race!

Scale-Sailing models are at most risk here as their sail areas are proportionately far larger than on full size craft. What is more when water gets during gusts "over the side" it stays in and sinking becomes ever more likely.

My pride and joy was only saved at all because the lake was 18 inches less deep than normal - so just one inch of mast was out of the rather dirty water.

Quick-release bouys are therefore quite vital for such models. What is more they at are least desirable for power boats with insufficient built-in buoyancy to still float when totally waterlogged.

By collisions or from "towering seas"; I have seen actually other boats sink without trace.

For the sake of one cork and some fishing line, a securely tethered marker bouy is one simple extra feature that can indeed save your treasured model!!

Dr John. F Leeds and Bradford. MBC. 😮😮😴

Have seen models with a floatation marker attached and wish I had one on my schooner when it sank. Recovered thanks to a friendly swimmer diver with a full size dinghy but would certainly of helped.
Not sure about using the marker cord to lift the model unless it is very light.
dave976

Nice bit of engineering there flaxbybuck! Never thought of using the mast to run the line through. I don't think it takes away from the model either. Very well done! I hope you never need it... RR 👍👍👍

I once read an article where a buoyant object was tied to the boat with string and then stuck to the deck of a boat with soap. Don't know whether it would work or not. I'm sure there are stickier things around than soap which are also water soluble but it seemed like a good idea at the time.
Best wishes to all, Tim

No good for your submarine ,but I made a float for my schooner that will act as a marker should it sink. I did this soon after seeing a friend's schooner sink. Fortunately it was in shallow water and we were able to spot the tip of the mast just below the surface. But it so easily could have happened in deeper water and not been spotted.
I made a float from a cork (from a bottle of bubbly, of course) and kebab skewer attached to a line that is a couple of meters longer than the known maximum depth of our sailing water. At deck level the line runs to a bobbin (or drum). I had to make all the elements of this strong enough to be able to lift the boat off the bottom by pulling on the line.
Thankfully I have not had to use it , yet !😉