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It is possible to orally inflate bondage wings at depth. I participated in gathering evidence for a lawsuit that involved bondage wings where the plaintiff claimed it was not possible to orally inflate the wings and get sufficient buoyancy to become positive. So we took the dead man's gear, a wetsuit, 15 or 20lbs of extra weight, two stages (if I recall I believe one was steel), and an extra steel 72 stage which I carried and passd to the diver at depth and went on a 230ft dive in freshwater (the fatality occurred in seawater which would have been even more buoyant). We documented on video at depth that the diver could achieve buoyancy using the power inflator and that after the wings were completely dumped they could be orally inflated to achieve positive buoyancy (several times). The demonstration proved the claim that the particular BC in question could not provide the lift was false. End of my involvement (as a safety diver during the exercise). Now if anyone would ask me if I would recommend a bondage type wing I would immediately say no. I tell people to cut off the cords on the wings they have but that still doesn't get rid of the baloon size some of these wings are (e.g. 100# of lift). As mentioned by several people on this list, the bungeed (bungled?) wings are not desirable IMHO because: 1) The ability to precisely control venting is compromised by the positive overpressure in the wing created by the elastic cords. The pressure anywhere in a submerged air bubble (the bladder in your BC) is equal to the hydrostatic pressure at the lowest (deepest) point on the bladder minus the weight of the air to the point in the bladder in question. This small pressure offset created by hydrostatic pressure is more than sufficient to properly vent a BC, with a degree of fine control. 2) A puncture in the wing may be catastropic as the cords tend to completely squeeze the wing in size. in a BC that has no bungees, an air bubble can be trapped within the wing and still offer flotation. 3) The bungeed wings are typically monsterous in size and the drag created by the crumpled mess can be prohibitive. 4) The location of a bungeed wing (maybe unless it is fully inflated), on a horizontal diver, causes the center of buoyancy of the diver (with tanks) to be farther below the center of gravity of the diver (with tanks) and therefore the stability of the diver is reduced. Note if you observe non-bungeed wings you will notice the two wing tips will be alongside the tanks. This is where the bulk of your nominal "in-flight" buoyancy should be from a stability viewpoint. If you are weighted properly this volume will be minimized offering sufficient reserve buoyancy if needed. 5) I've had people tell me you need 100#s of lift in a BC in the event your buddy loses buoyancy and needs help - therefore you should use bungees to consolidate the large wing. To that I say bullshit. Of course you and your partner should be weighted correctly. Yes you can inflate a bungeed wing orally and you can get sufficient buoyancy in most cases, but the negatives far outweigh and perceived advantages (which I can't think of) so why bother with something inferior? Think Occum's razor!!! IMHO, Doug -- Send mail for the `techdiver' mailing list to `techdiver@aquanaut.com'. Send subscribe/unsubscribe requests to `techdiver-request@aquanaut.com'.
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