Sure, thanks for considering.Originally Posted by aainslie
nick
Welcome to the Cave Diver's Forum.
Sure, thanks for considering.
nick
It seems to me that taking a stage tank (al80) and dropping it off somewhere along the way might be a good idea. I know this has been talked about ad infinitum, but really, why not just teach it as standard practice? If you dive thirds, and given all the little bits of conservativism along with calculating thirds, why not have a tank waiting for your team somewhere closer than the surface? It would sure make a person feel better to know that plenty of air is waiting ahead.
skip
"Learning the techniques of others does not interfere with the discovery of techniques of one's own." B.F. Skinner, 1970.
There are pros and cons. We've done this as a two person team, taking a stage in part way to where things get tight or to a convenient drop point as a means to increase the reserve gas. The only real advantage is one of logistics as you can use the same stage for the whole trip with no need to fill it.
In the extreme you can carry one with the team to max penetration as in essence with 260 ft of back gas it is only about 9 cu ft short of being an entire third all by itself so it and not much more back gas will potentially get an OOA diver out, assuming the exit goes as smoothly as the entrance.
However, from another perspective it makes more sense just to have each diver use a stage on the dive to increase the back gas reserve on the entire dive in addition to having some reserve gas closer to the exit. The disadvantage here is that you end up needing 4 stages to cover two divers making dives per day between fills and it doubles the number of tanks you are hauling around.
However, even if you fall prey to the temptation to just press farther and dive to thirds again, it still reduces the hit of a lost gas scenario as no diver will have a total gas loss as there is still the reserve third left in each stage. Of course that gets us back to arguing about the merits of diving stages to thirds versus half plus 200, but obviously using them this way argues for using the "thirds" approach to spread the reserve gas out a bit more rather than having all the reserve in a diver's backgas.
Skip,
I hope that on longer dives, that's totally the message.
I had 4x the gs necessary to exit. That's equivalent to diving 5ths on OC. And I barely made it out.
Food for thought. On previous trips I dropped a 40 by the jump to the bone room. After the dive I heard someone making cracks about what idiot thought a 40 was any use at that point?
Well, it's a LOT of use if you're running out of gas on your way home after some unexpected detours...
Andrew Ainslie
Almost extinct cave diver
Sounds like it takes a lot of gas to replace a redundant brain saying, "Hey, wrong way stupid!"
Careful there mate! I have had buddies going the wrong way, and they wouldn't accept any input. I actually had to tackle one buddy, and drag her in the right direction. She was going upstream in Devil's Eye, on goldline, passing arrows, and still thought it was the way out.Sounds like it takes a lot of gas to replace a redundant brain saying, "Hey, wrong way stupid!"
Another buddy was heading down a dead-end passage, and wouldn't believe me that it was wrong. Since it wasn't far to the end, I just followed him to the EOL. Then he gave up, and followed me out.
The "redundant brain" concept is highly overated.
It could have been said with a bit more grace and tact, but I agree completely.Sounds like it takes a lot of gas to replace a redundant brain saying, "Hey, wrong way stupid!"
This incident truly does illustrate the point that while you can bring the reserve gas a buddy would have provided and even clip a couple back up lights on the tank(s), none of that will ever provide the back up of a team mate's brains, eyes and hands.
Marci and I were recently diving a new to us and infrequently travelled by anyone tunnel with very old line with most of it covered in sand and silt. Going in, I was gently pulling it out to ensure continuous line and in the process missed a tee. Marci - doing the redundant brain thing, caught the error and marked the tee. Much later, on the way out she new exactly where we were at and when I noted the her cookie on the tee the gravity of the suituation was apparent. Had I been solo, finding a preveiously unknown and unmarked tee would have casued some confusion and at best would have resulted in some delay while I ensured which way was really out in the very low viz as all the silt stirred up deeper in followed us out. There were other safe guards in place (knowing approximate distances/times, key easily identifyable features in the passage out) so it was not a kajor threat underthose conditions. However had I had an emergency, been under stress and short on gas, that little bit of extra confusion could have created a major delay.
The possible scenarios are interesting - had I taken the wrong passage, then recognized it and reversed course, but missed the (now marked) tee again, I could have ended up going back into the sytem until I again realized the mistake in now very low viz. Making those kinds of errors, especially at any kind of depth could quickly eat through a lot of gas. Personally, I like having Marci alongf as she is avery solid diver and as team members we almost intuitively know what the other is thinking. I also know I am a very good diver with very good cognitive problem solving abilities who handles high levels of stress very well. However I also know I am not perfect and I can use that same intellect to readily envison what could go wrong in most situations. Knowing all that, in my opinion, makes diving solo a poor choice in all but an extremely limited set of circumstances.
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Forrest is not incorrect that a buddy can add confusion, but that's where backing each other up and properly laying and marking the line is important. In the above case, a poor buddy would have really sucked and added to the delay, but that woudl not have happened sas I make dedicated effort to never dive with a buddy known to be poor and I never take a unknown/untested/untrusted buddy anywhere challenging where that type of confusion could occur.
It's not just having a buddy that matters, but rather having a trusted team member and that is exactly what James is talking about.
+1 @ 100% Thank you!!!
I disagree. Dive at Kitty, 3 weeks ago, with my most trusted team member, Bobby. We communicate to play around, I had seen the T to two sinkholes, he had not. So he goes up to our entrance sinkhole (Kitty) then turns back. We surface on the other sinkhole and he says: this is not right, it is not where we came from. I thought he was playing and wanted to check the other sink. He was confused. I did not trust him, said we should go back to the other hole. Apparently I was right.
Everyone can get confused. As much as Bobby is more experienced than me, I doubt him all the time. That's what he has taught me.
Xenia, a.k.a. Local Zip Code Diver
or choosing quality buddies is highly underrated?
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