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Hi, I said this: > Hi, > > Has anyone else noticed that the manifold/indep debate is exactly the > same as the Spare Air/pony debate? To which Ken replied: ******* No it isn't. Because I said so. With independants you can't get all your air at all times. Yes, if you have a free flowing poseidon you'll could conceivably stain your dry suit. However, remember, with manifolds your buddy is your backup air. ******** Ah, but we were talking *solo* diving (even if most of the posters didn't realise they were solo diving). OW TMX is virtually impossible to do as a buddy dive. ******** One thing you mentioned in a previous post was about your regulator failure. You said, "if I lost 90 cu ft. of air I would really be upset" (or something to that effect). Excuse me, when your regulator went kaput and you couldn't get to any of the air that was in that tank, how much air did you lose? If you were before thirds and using 95 cu ft. tanks I'd have to guess at least 60 cu ft. of air were lost. "But the tank still has the air", but if you can't get to it, then it's worthless. ******** I was just on thirds as it happened. So I had used around 40 cuft. (thirds after I'd subtracted enough air for the deco from both cylinders). So I lost around 75 cuft. Thing was that I *knew* I still had around 75 cuft left. Ie 40 to get out and 35 for deco. If I'd lost 90 cuft (from the remaining 150) then I would have only had 60 cuft left. I would have got out (just) and then missed a lot of my deco. I would count myself as a very unhappy camper. Had it been a no stop dive, I would have breathed water 15 cuft short of the exit. ******* Manifolds are NOT an ideal situation if you are solo diving. Under those circuimstances you should have some alternative backup gas supply. However, even something like blowing a burst disk will not vent all of your gas instantaneously. ******* If you are diving thirds then a blown disk at thirds will do you in. (I count a blown disk on a part full tank as not worth worrying over, but you bought it up!) Say you are using 3000 psi cylinders. You have used 1000 in, and are at 2000. The disk blows at this point. You close down the isolation valve. This takes you only a short time. You will now have zero in one cylinder, and *something less* than 2000 in the other. 2000 to get in, less than 2000 remaining to get out. BANG, your dead. ******* If you dive solo, independants work quite well for that configuration. However, if you are diving independants within a buddy team then either everyone in the team should dive independant, there be at least two manifold divers, or the manifold diver should prepare as if diving solo and bring the appropriate bail out gas. When diving in a team, manifolds make good sense. You have access to all of your gas at all times, and the simplicity of use. ******* But you can't dive OW TMX as a team! ******* Let me ask you this. How many people have died from a manifold failure? Now how many people have died because of complications (human error) with independants? ******* I don't know the answer to either question, but I can repeat what I said to Carl. In a place (like america) where everyone thinks that manifolds provide a redundant system (when they don't) is a solo diver's death while using a manifold put down to solo?, or to diving with a single gas supply? The only death I have heard of "caused" by independents, was where the diver turned independents into dependents by his method of operation. He totally consumed one cylinder, then switched to the other. (ie he turned it from a double to a single gas supply). One day he couldn't find the next regulator and drowned.... Would he have been better off with a manifold? Probably, as long as nothing ever went wrong. Cheers Jason =:)
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