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Hello, George recent remark on the possibility of positively using the gas trapped in one side of the bladder to counter or restore an offset balance reminded me of an old project I never came to dig out any further than just a couple of twists. The old Draeger FGT military nitrox SCR did not have any buoyancy device except the counterlungs. If it had had one , one marine might still be alive, who drowned because of a malfunction. Poseidon/Diverite developped a Wingjacket, the Luigi, perhaps a major convolution ( 6! dump valves, among else.) I first did not want to fix a bladder directly to the fiberglass turtle shell, and thought of different solutions. A common backplate was out of question because of the V-shape. Filing through my resources, I saw 2 oldstyle horsecollars, beltbuckles and crotchstrap all quickconnects and adjustable in length. So , hoses mirrored for left and right, belts adjusted, and one over each arm, belts connected, collars neck strapped together, crotchstrapped to hold it down. But now, how do I get into the rig ? Shoulderstraps lengthened for miles, awkward. Likewise to guide them through at the back. CF! That's where it stopped. I restarted now with a bargained Transpac, thought the quick disconnect shoulderstraps would ease things considerably. Well not really that much, was still difficult to don the crotchstrap, and guide the shoulderstraps from below to the chest area, had to pass them through each bladder's inner ( neck, now shoulder) diameter. I should add here, for the faint hearted, that my main concern was, how would it behave in the water, not to produce anything finally approved . Getting in and out was a major cf and Maffatone came into my mind inadvertently. So I added an Al 80( 10l 200bar) and my Apeks, and jumped into the pool. Wait, before I did so with only the two bladders. Lift capacity was big as expected, stability good, but kept you lying face down. Eqipped completely( still without suit and weights) it was much better. At the surface, well inflated it was rocksteady laterally, with a good freeboard for free airways. From a prone position , it lifted you backwards, but still rather slow. This would be much better with a wet- or drysuit, and weights. The really good thing was the diving. A perfect balance ( if you kept it balanced by equal addition, very easy to dump completely, no air pockets, and turning in any direction easy, especially rolling frontwise or backwise , like a hamster in a wheel ;-), only being steady in at any tilt angle. Way beyond my best expectations. Water resistance was not easy to judge, since I had pool fins. I think it may have been a bit on the high side. Well I do not need to comment on the need of 2 inflators here. In fact, my further design ideas went to a connection of the now separated volumes by using the former shoulder dumps/OP-valves and the bottom dumps, while still maintaining the possibility to dump. I only might have scratched the posibilities of this concept, or it might turn out to be a flow. What impressed me , was the total ease of balance, and the natural stability. I didn't have my standard rig with me ( limited amount I was willing to carry to the clubs pool session), so I fail to compare it on a one by one basis. Still my feelings where those of an even better balance, drag and the donning left aside now. Something worthwhile to work on further, if only for curiosity. But what else keeps bringing us ahead. Matthias PS: for the really faint of heart, add two horsecollars round the upper legs ;-) -- Send mail for the `techdiver' mailing list to `techdiver@aquanaut.com'. Send subscribe/unsubscribe requests to `techdiver-request@aquanaut.com'.
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