[Nick Flint Posts: 5083 Status: Offline]

I added FULL length  2X 12  inch foam down the lower (outer) side plenum wall on My Falcon (lengthened Kestrel).
We did an on water stability test  and struggled to get ANY appreciable listing with "many occupants", AKA = LOTS of
The foam was glassed in at birth and was providing buoyancy from the moment it touched the water. Also added hug strength and only small increase in weight- no prob on this cruising machine. Carried the whole family in absolute safety over many years of sea and river travels.

[joncurtis Posts: 2098 Status: Offline]

yep!

[Ian Brooks Posts: 3607 Status: Offline]

100mm thick. which really is the wrong place for it, id prefer more on the sides to provide stability whilst floaty.

When I looked at the floating stability of another craft with similar floor slab it was negative - that is, it will float just fine but upside down! Not quite what you want 😂 as the owner discovered.

The BBV may be ok if the slab is wider but if you can get some foam in the plenum it might add confidence

[joncurtis Posts: 2098 Status: Offline]

yeh will defo be PU as need to glass in place, bit like other craft the entire floor is a slab of foam, id say 100mm thick. which really is the wrong place for it, id prefer more on the sides to provide stability whilst floaty.
 

[Nick Flint Posts: 5083 Status: Offline]

All sound points Jon. Can I also suggest you avoid polystyrene foam and go for modern closed cell  PU foam to avoid petrol dissolution and add to structural integrity. I understand you probably know this kind of thing as you are "a well seasoned operative"  but mention it any way in part for discussions.
If you wish I could enlighten you further ref Loch Fyne, on PM perhaps if you're interested,,,,,

[joncurtis Posts: 2098 Status: Offline]

ah, so someone mentioned a BBV 6 did not do well at a loch but i did not know the details.
I can understand why that might happen, there are some build quality issues with the one i have, its old mind though, and it does not help that someone has drilled holes in the floor and the slab of buoyancy foam is saturated.
but the way its built i can see how the slab of foam in the base, even without the holes could saturate with water causing major issues. the plenum on mine seems to like to fill up with rain water which is also not great.
so after i get the drive finished and completed the crane build, its getting flipped over, the bottom cut out and new foam, free flooding/draining plenum, extra buoyancy down the sides and whilst im doing that a partition skirt as i dont fancy going through the widescreen when it ploughs in.
i did consider not fitting the back of the enclosed cabin, but a nice heated cabin with bucket seats and a cup holder is desirable, now my body is failing.

[Nick Flint Posts: 5083 Status: Offline]

or----- operate without the hard top doors to drastically reduce the risk of dying. Loose fitting soft top over the T bar?  Much lighter. Ive removed my flood light from the top of my duct as it was such a pain to get in my workshop. Certainly a bouyancy / floatation device would be more intrusive than my light.


 I assume you are revisiting the craft floatation aspects after the Loch Fyne BBV 6 "unwillingness to float"?      :'(

[Ian Brooks Posts: 3607 Status: Offline]

You could use the auto C02 gassing system from a life jacket to blow the top off with a little thought!

[joncurtis Posts: 2098 Status: Offline]

its the screen out of a saab 900, suppose i could get a generic seal strip, the one i have off a saab has been soaking in silicon oil for the last 4 months. it has the strips on the outside.
good idea if rolled over on land, but not sure there would be time to do such a thing if upside down on water. was thinking of putting a self righting bag, like you get on a rib, ontop the duct.

[Al Posts: 1014 Status: Offline WWW]

As an added safety feature, maybe fit the windscreen with the old type rubber surround, but instead of having the rubber sealing insert on the outside, have it on the inside with a pull toggle in both the top corners of the screen.  That way you could pull the rubber insert out easily the kick the windscreen out.  It's not perfect, but could give you an escape route in an emergency on land or water.

[joncurtis Posts: 2098 Status: Offline]

anyone got any experience of self righting systems for boats? was thinking about putting one on the top of the duct on the large craft. i have a full enclosed cabin to go on this stupid great craft i have, and am worried what would happen if it goes over.

[Ian Brooks Posts: 3607 Status: Offline]

My thoughts on the matter…

Having a “little experience “ of actually needing a life jacket I can say that 160N is sufficient. When I went in wearing heavy clothes I did not surface until the jacket went off. Once it did , I popped up like a cork.

I would also say that unless trained and well drilled I do not think you would easily find the toggle and inflate a manual jacket. You’ll be in the cold and dark water and having experienced it, I cannot imagine having to fumble around for a toggle - would you even remember which side it was? Maybe you would - but not a chance I’m
taking!

Ian

[John Robertson Posts: 5282 Status: Offline WWW]

In 'normal' UK coastal water, unless you're wearing a survival suit, the cold shock will make you unable to manually inflate a lifejacket,  Something to consider versus the odds of getting trapped under a hull (which is a 'safe' place so some time is available).

The auto (or manual) jackets should be checked every year.  Inflate the bladder (using an air pump) to check for bad leaks (if it stays inflated for 3-4 hours then its good - you won't survive longer than that anyway  ).  You should also check the gas cylinder is in date  (provided it isn't corroded and weighs what it says on the stamp then I usually keep it - but to be absolutely certain, replace if expired).  Also worth checking the trigger on auto jackets looks good.  I'm still using 25 year old auto jackets (not with the same cylinders!).   In my experience, the bladder is the bit that eventually fatigue fails (or the outer velcro gives up).

[Steve Holland Posts: 1649 Status: Offline]

RNLI use manual inflation jackets. Personal choice at the end of the day, pros and cons with both as always.

[rossfloyd Posts: 2053 Status: Offline]

I've gone away from auto inflation jackets and now have manual ones.  As you say, the thought of getting trapped under an upturned hull is not very appealing.  Having done the sea survival course I felt that a manual one was just as good for the likely scenarios and to be trapped under an upturned hull with a high flotation jacket and have to deflate it to swim clear ...and by inference discharge a lot of co2 into a confined space where air was at a premium .. would not be for the best.


We did find incidentally that during the survival course being prepared to deflate and inflate the jacket as needed to alter your buoyancy was really useful... but that was in a heated swimming pool.  I am not sure if my brain would consider this option in a panic situation in cold salt water.