Lessons learned- embarrassing but true

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Why is a rebreather bad for unexpected depth changes? I think that's where my rebreather excels.

I'd prefer to teach in eCCR. I don't teach while on CCR, but I will once I become a CCR instructor. Here's why.

About two years ago I was teaching a Trimix class at Eagle's Nest. We made our dive to 200'ish feet for the specified period of time. It was basically follow the leader. Everything went off without a hitch until we got to 150'. We all had computers, but were running run-time tables as our primary. We got back to our ascent point about two minutes early, so we were waiting out the clock so our run-time tables were on the money. When it became time to ascend, a student froze. I gave him a thumbs up. Nothing. I asked him if he was okay, he answered okay. He was breathing, awake, eyes open and responding to questions, but would not ascend. He would not move. I finally grabbed a hold of his harness and started moving up, we were already late for our tables. Once we moved up 20 or 30 feet, he seemed to snap out of it. But I'm already worried at this point. I don't know what might happen from here. He could bolt for the surface or the floor, become unresponsive again, who knows. So I'm babysitting him like never before. I've got one hand on him, but of course, I've got my all of my bottles to contend with, gas switches, air breaks, venting the wing, venting the drysuit, etc. I also have to watch to make sure all his stuff happens without a hiccup. Is he breathing the proper bottle/reg. Did he change his computer after the gas switch. Blah blah blah... And there's another student. Now, this is doable, and it's the reason we limit class size, but on eCCR its a lot easier.

On backmounted doubles do I mix the best mix for the planned dive, or do I mix just in case the student ends up on the floor? If I mix for the floor, now our deco doesn't line up. But, if I mix for best mix for the dive, and the floor is 100' below us and something goes wrong, now I risk myself going to rescue him. How many stories are on Scubaboard about students descending way below their instructor. It hasn't happened to me.... yet. But I plan for it. Given the right amount of idiocy, and just about anything can happen, I believe. -- On my rebreather, I can put in 10/60 have the best mix for the dive, and if some goober ends up on the floor, I can go get him. I hope this never happens, and I think I weed out crappy students pretty well, but this is a benefit to the rebreather.

So, lets assume a student is going to freeze, but this time I'm on an eCCR rebreather. What do I have to do? Well I can tell you what I don't have to do. I don't have to manage additional bottles. I don't have to switch gases. I don't have to do air breaks. Both of my hands are free to hold onto my student if necessary. Because when students freeze up, they forget stuff like venting their suit and wing. They forget to change their computer and gas switches. The less I have to do for myself, the more I can focus on them. And eCCR allows me to do that.

I believe diving a rebreather at trimix level depths is safer, especially if you're teaching. That's just my 2cents. I'm sure all of you will disagree. lol

Oh jeesh. I know you as much a troll here as in person, but this isn't about you or your student and how you need to wait or not to "get with your tables".

Sorry but instructors need to be role models for their students and demonstrate how to do the dive "right" start to finish. That means no mixed teams for classes period.

---------- Post added December 18th, 2014 at 09:19 PM ----------

No, I think you misunderstand....
You guys were there for 20+ years. Less than a week after we had access, we extended your line 200'. LOL
It really wasn't our plan, certainly wasn't intentional, but it was so easy with the proper technology. LOL....
Really happy right now you guys didn't embrace CCR

Funny how even without any time/gas pressure you can't survey it though...
 
Or not teach trimix diving at places where you have those kinds of potential problems? Or everyone dives the same gas? Or you don't take students into a cave environment for trimix training?

Good lord.

Just to be clear there was no cave
 
Was this the first dive of the course? It certainly seems like either it was or enough dives were not done in a training environment before this one. I don't care how experienced the individual divers are if none of them have dived together at all or even very much then team dynamics need to be established in a benign environment. During the decompression classes I teach we spend 5-6 dives working on skills and team dynamics before we ever venture out to do a real decompression dive. I need to know my students can handle pretty much anything before they HAVE to handle it. I also don't ever have more than 3 students and usually only 2. A similar incident happened to me years ago during my decompression training. There were 4 of us as students and the 2 teams became separated putting my instructor in a very uncomfortable, and potentially bad, situation. 3 students can be difficult enough to manage, especially if the team dynamics aren't there. 4 students can be impossible to manage.
 
Yeah, I can't park on the grass, but we did add 200' to your line. Bwuhahahaha....

congratulations on using your CCRs to add a scrap of line to the end of what the team put in on open circuit 20 years ago. if you're not going to survey it you might as well go big and call it 1000'.
i'm sure the park can expect the map and connection to indian any day now.
you guys are a real piece of work up there.


good luck on your exploration and maintaining a good relationship with the park. deleting your last moronic thread was a good idea.
aquatic science association. wanted: one aquatic scientist.
 
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I also don't ever have more than 3 students and usually only 2. A similar incident happened to me years ago during my decompression training. There were 4 of us as students and the 2 teams became separated putting my instructor in a very uncomfortable, and potentially bad, situation. 3 students can be difficult enough to manage, especially if the team dynamics aren't there. 4 students can be impossible to manage.

There were only 3 students. Diver#1 in the story was THE instructor. Divers# 2,3,4 were the students (even though some held instructor ratings).

I also had a bad experience with 3 students, and find it to be VERY borderline (not an instructor, obviously, but was one of the students suffering). I think 3 students can be done safely if the dynamics are there and if the students are mostly over-qualified for the course.
 
Was this the first dive of the course? It certainly seems like either it was or enough dives were not done in a training environment before this one. I don't care how experienced the individual divers are if none of them have dived together at all or even very much then team dynamics need to be established in a benign environment. During the decompression classes I teach we spend 5-6 dives working on skills and team dynamics before we ever venture out to do a real decompression dive. I need to know my students can handle pretty much anything before they HAVE to handle it. I also don't ever have more than 3 students and usually only 2. A similar incident happened to me years ago during my decompression training. There were 4 of us as students and the 2 teams became separated putting my instructor in a very uncomfortable, and potentially bad, situation. 3 students can be difficult enough to manage, especially if the team dynamics aren't there. 4 students can be impossible to manage.

It wasn't the first dive but it was the first one where something went wrong.

dynamics aren't great yet. That's true.

R..
 
It wasn't the first dive but it was the first one where something went wrong.

dynamics aren't great yet. That's true.

R..
so what are your thoughts on the class? what is going to happen next in the class according to the instructor?
 
Why is a rebreather bad for unexpected depth changes? I think that's where my rebreather excels.

It's not about MODs for me. Bouncing up and down in the 0-100 foot range is a pain on CCR - dump the loop, add to the loop. Having to stop your mad plummet in pursuit of a student because you've collapsed the loop and need to add dil is - I think - an unnecessary distraction. Ditto adding one more expanding bubble when someone is going up. It's not unmanageable, but nor is switching to back gas. Your mileage clearly varies - I'm only 80 or so hours in on the great rebreather journey.
 
Something isn't clear in your story... Was it the first time you dove together as a team? Did you dive before class/instruction? Since you all come from a different background was there clear understanding on the procedures and failure procedures?

That's of course the good thing about GUE. There is difference in quality in GUE divers, but the base-line training is very high and you speak the same language "procedure"-wise. So yes I've done 50m dives or cave-dives with GUE trained divers without any previous checkdives or big discussions but that's possible with GUE because of the base-line and procedures. I wouldn't do this with a mixed qualification/background team.

Why do you think that being cave trained makes you any good at mid water ascends? I found C1 easier than T1, just because of that exact reason... mid-water stability, rock solid ascends, task-loading in mid-water. My background was such that I had much more experience with ascends with reference (following bottom) than with blue water ascends. In caves you have a bottom or ceiling most of the time as reference so with regards to ascends that was not such an adjustment.

Just saying that being cave trained doesn't give you a "mark of excellence" in cave diving let alone in any other environment... it just states that you 've been trained to dive in caves, nothing more.

Thanks for posting btw.

PS: After doing Tech 1 and doing a lot of blue water no reference ascends (some even without bottom-timer), while under significant taskloading, it has become much more instinctive to do those ascends.
 
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