Hopping my way to full cave...

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am planning a double lines whale bone dive for the day after tomorrow. Instead of a 40 minute slog of a swim to the jump
LOL, interesting you mentioned this. For my next trip, I'm planning to slog with two stages for the add'l search time. It's a bit depressing to think it's only adding about 6-8 mins (a guess considering the increased drag). A DPV certainly seems like the better choice!
 
LOL, interesting you mentioned this. For my next trip, I'm planning to slog with two stages for the add'l search time. It's a bit depressing to think it's only adding about 6-8 mins (a guess considering the increased drag).

I can't find the previous two attempts in my log, but the last time I swam Hill 400 slick it was 30 minutes to the 1,200 arrow slick with 108s. And about 35 minutes to around the same area when I swam to the Bats with a single stage. So 40 minutes sounds about right with two stages.
 
LOL, interesting you mentioned this. For my next trip, I'm planning to slog with two stages for the add'l search time. It's a bit depressing to think it's only adding about 6-8 mins (a guess considering the increased drag). A DPV certainly seems like the better choice!
Depending on your experience level and sac rate a single stage is very very doable. I would argue 90% + do it on a single stage. Note I’m not saying don’t take extra gas. Extra is always good. But slogging an extra stage for that dive is more of a headache than it’s worth imo.

Hint. If you’ve never found the whale bones, the big ass knot in the line is a huge clue
 
I thought it would be good to put this here as well, as it is part of my journey. You could click the quote or this link and see the rest of the discussion.

TLDR: What really is an experienced diver, because I don’t feel like one.

So, this might be a bit disjointed as this post is spurred on by the thoughts I had while sitting for 25 minutes of deco after my 400th dive the other day, and the boredom of having to wait for the hurricane to pass by close enough to close things but not close enough to cause any major hazard. I often spend that time going over my dive and then just sinking into my thoughts, which in a world where we are constantly being stimulated is kind of nice, particularly in the previous 90 minutes where my head was entirely on the dive and not thinking about the outside world at all.

Speaking of the dive, it was fantastic, I went to the Ice Room, I had been working on most of the last few dives to lay the groundwork to get to this room. It is mildly difficult to get to, it is about 2,000ft into the cave with the last 800ft being sections that are fairly low that require careful swimming. It is a rarely visited room due to the difficultly, as luck would have it a local instructor was taking his DPV students to that room, and they were in backmount. We met at the last jump, and it was pretty silty getting worse as I progressed down the line, getting to around 5ft at the worst, until I get through the final low section to the room, like breaking through the clouds in an airplane suddenly it was the normal 50+ft Ginnie clear vis, and I am in a stunningly large room that with exception of the domed ceiling was largely Ginnie’s natural black color.

But going back to my deco thoughts, while gearing up for the dive I often get distracted chatting with people I know. On this day I was talking to someone that I met during my early days of cave training, and I mentioned that this would be my 400th logged dive and a majority of which were cave dives. He said after seeing me the prior week leading a newish cave diver on his first dive to the Henkle, that I almost seemed like an instructor going over the dive plan with him extensively making sure he understood everything. That it was interesting seeing the transformation from a new cave student to an experienced cave diver capable of mentoring others.

The reality is that the extensive briefing was masking my insecurities, I felt that he was going to rely too much on me and wanted to transfer as much of the responsibility back to him as I could. Having him lead in, and check arrows to make sure he knew where he was. That way if something went wrong at least he could have a decent cave map in his head, which I feel makes it easier to deal with emergencies.

Because I don’t feel like an experienced diver. On every dive I see and learn something new, even when going to areas that I’ve been to dozens of times before. I don’t feel like an instructor that probably has done these dives thousands of times and as such it is routine. That they have the experience to be the safety net that new students need.

Maybe it is because I never really had a plan when I got into diving and then cave diving. My deco instructor, James Blackman of Miami Technical Diving, did a video recently for the start of his trip to the nuclear fleet in Bikini Atoll. He mentioned that you should have a goal to work toward and a plan to reach it. The thing is, I’ve never really had one. I got into diving on a whim. I got into cave diving as a combination of wanting to be a wreck diver to see WWII wrecks and enjoying a cenote dive in Mexico. I don’t have a grand plan; I just want to see what is around the next corner. Just as I knew that I would eventually get into DPV diving when the time is right, I know eventually I will have to go CCR once I reach the limits of what I can do OC.

Even with that knowledge, I simply don’t have any goals in mind. Sure, it would be nice to visit the various deep rooms in Eagles Nest, but that isn’t really the goal. Simply to keep pushing into areas where logistically it would be hard to do on OC. So, thinking back I never really saw any plateaus in my diving in the past nor do I really see any in the future. As such I have a hard time considering myself an experienced cave diver.

Well, I am going back to watching my palm fronds get blown off my trees.
 
Since a friend recently did Cave DPV and we had a discussion about gas planning I decided to crunch some SAC numbers.

My normally Ginnie gas planning for swimming is 0.7cuft per min. I didn't have a chance to update that number recently as it slipped my mind during my Ginnie swim dives the past couple of weeks.

But yesterday I did a DPV dive at Ginnie and it came out to 0.52cuft per min for bottom phase. With deco at 0.38cuft per min.

A recently a stage swim dive at Peacock with zero deco and honestly no real safety stop just a slow ascent was 0.62cuft per min, 0.60cuft per min without the stage.

So my scooter SAC rate is about 25% more than resting but 40% less than swimming in Ginnie. And my scooter SAC rate is 20% less than swimming in a low flow cave.
 
Since a friend recently did Cave DPV and we had a discussion about gas planning I decided to crunch some SAC numbers.

That’s me! That’s me! :)

I’m very much looking forward to fleshing out those kind of numbers myself. As part of the class of course I did a 1000 foot swim towing the scooter, so I have a usable number for gas planning, but I’m really looking forward to getting a better understanding of all of those numbers and how they change in different circumstances.

I really think I’m going to have to break down and buy an air integrated shearwater. :-( I know I can do the same thing by carefully recording start and stop pressures, start and stop times, going into the logs and pulling out average depth information for that section, etc.

Or I could just spend the money. :)

Unless anyone else has thoughts about a more effective way of doing that?
 
That’s me! That’s me! :)

I didn't want to name names until you posted about it.

I really think I’m going to have to break down and buy an air integrated shearwater. :-( I know I can do the same thing by carefully recording start and stop pressures, start and stop times, going into the logs and pulling out average depth information for that section, etc.

Or I could just spend the money. :)

Unless anyone else has thoughts about a more effective way of doing that?

IMHO AI makes it easier to have a wealth of data, like I could go back and get non-stage data for my swim dives. Or compare them between the various caves. And when I want the most accurate data I just write down my stage pressures to plug into a spreadsheet.
 
I really think I’m going to have to break down and buy an air integrated shearwater. :-( I know I can do the same thing by carefully recording start and stop pressures, start and stop times, going into the logs and pulling out average depth information for that section, etc.
Don't buy - borrow ;-) This is one of the few times when you need extremely precise calculations. Were you just in Cave Cave country?
 
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