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spearfisherman55
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spearfisherman55:Who do you teach for?
Yeah... an what if it takes 32 minutes to get him untangled instead of only eight? What will you do then???derwoodwithasherwood:Actually, the original question is an interesting one. Let's change the circumstances slightly, keeping the scenario within a properly planned recreational dive:
We are engaged in a hypothetical dive at a maximum depth of 100'. Approaching our planned NDL of 17 minutes, I have 1400psi remaining. My buddy unexpectedly becomes entangled in some monofilament hooked up on a log on the bottom. He turns to see what he is caught on and gets further tangled. A bit of tugging on his part and suddenly there is tangled line everywhere. Seeing he is in difficulty, I move in to assist, but do so cautiously to ensure I do not become ensnared. I carefully cut away the line with my shears and line cutter, but this takes, oh, say 8 minutes. Meantime, my buddy is consuming air at an elevated rate due to increased effort and stress. In fact, so am I, so now I have 700 psi left and he is down to, say, 300 psi.
At 30fpm, we will each consume 200 psi or so during the ascent, if we can calm down and get our breathing back to normal. My tables (NASDS) give me a 6 minute deco obligation at 15 feet. My buddy will run out of air before then and will be breathing from my octo. If everything goes right during the ascent, my buddy will be OOA and I will have less than 200 psi left when we surface.
That's cutting it awful close and it depends on getting our air consumption rates down to normal. Should I stick to the 30 fpm ascent rate and be prepared to blow off some deco time if we run out at 15'? Increase the ascent rate to, say, 60fpm to reduce air consumption and ensure we meet the full deco obligation? Or is there some other strategy that should be considered?
derwoodwithasherwood:Actually, the original question is an interesting one. Let's change the circumstances slightly, keeping the scenario within a properly planned recreational dive:
We are engaged in a hypothetical dive at a maximum depth of 100'. Approaching our planned NDL of 17 minutes, I have 1400psi remaining. My buddy unexpectedly becomes entangled in some monofilament hooked up on a log on the bottom. He turns to see what he is caught on and gets further tangled. A bit of tugging on his part and suddenly there is tangled line everywhere. Seeing he is in difficulty, I move in to assist, but do so cautiously to ensure I do not become ensnared. I carefully cut away the line with my shears and line cutter, but this takes, oh, say 8 minutes. Meantime, my buddy is consuming air at an elevated rate due to increased effort and stress. In fact, so am I, so now I have 700 psi left and he is down to, say, 300 psi.
At 30fpm, we will each consume 200 psi or so during the ascent, if we can calm down and get our breathing back to normal. My tables (NASDS) give me a 6 minute deco obligation at 15 feet. My buddy will run out of air before then and will be breathing from my octo. If everything goes right during the ascent, my buddy will be OOA and I will have less than 200 psi left when we surface.
That's cutting it awful close and it depends on getting our air consumption rates down to normal. Should I stick to the 30 fpm ascent rate and be prepared to blow off some deco time if we run out at 15'? Increase the ascent rate to, say, 60fpm to reduce air consumption and ensure we meet the full deco obligation?
Or is there some other strategy that should be considered?
Rick Murchison:...This reminds me of reporters asking Alan Shepherd back in the Mercury days "what if this happens" and "what if that happens" until Alan finally said "Well, some days you eat the bear... and some days the bear eats you. If all of those things happen at once then I guess I'm just dead."
Rick
spearfisherman55:I went to the Scuba Rangers camp there about 5 or 6 years ago.