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victorzamora

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Have you guys considered a "cave mode" for deco calculations? I don't know what to call it, but my thought was to make it something similar to the @+5 but actually regarding exiting the cave. It won't work for all caves (high flow, traverses, non-standard dives, etc) but since you know the profile taken to get in you know the theoretical profile to get out and should be able to have a TTS after the exit is made. I was doing a dive in "Hole in the Wall" (a no-flow FL cave of moderate depth 70-100ft) and had a fairly extensive bottom time. The average depth was much less accurate than I planned, so I was "flying" the computer. When we turned, we had gas but were afraid of racking up too much deco. If the computer had a function where it reversed the profile we took to get there (time and depths) and told us about what the total deco stop time would be if we turned then it would've saved us a lot of hassle. We had just breached NDLs by a few minutes (I think we had like 7min TTS, at 90ft) but ended up with ~45min of deco. The computer estimating it would be nice.
 
So what would you do, mark the entrance on the computer with some sort of time hack or something so the computer would equate that depth/time to the entrance and then recalculate from there? I'm assuming the issue is that the predictive calculations are not accurate because of the potential sawtooth profile in the cave and you'd like a more accurate TTS display? I'm trying to understand what the problem is with how it works now.
 
There'd be no reason to mark the entrance, so it should be completely hands-off. When MOST cave dives are started, you swim in, drop off your O2 bottle (if applicable) and then run your reel to gold line. You don't really waste any time....when you hit the water you head straight for the cave because you don't want to waste your gas. When the dive starts, the cave dives starts. Therefore, there'd be no need to "mark" it. Like the @+5 having a prediction to your dive at that depth for 5 more minutes, I'd like to know my deco obligation if I turned the dive around right now and dove the exact same profile I dove in, but in reverse.

The problem with TTS is that it doesn't work in caves. TTS means you're surfacing straight up, right now. Well, I've been 50min+ from the surface in some cases. TTS was like 6min (3min due to 100ft of ascent, 3min due to deco) and it took me a 85min TTS. 50min of swim back to the surface plus 35min of deco. I'd like to know what my deco obligation would theoretically be when I turned the dive. THAT is where TTS fails for cave diving.
 
Ah ok, now I understand. Interesting feature for sure.
 
yeah, so you can always mark your time back to the entrance of the cave but unfortunately have no idea how long the stop is going to end up. What Victor was saying is if the TTS had a "cave mode" where instead of TTS being 30fpm+ deco obligation, it would essentially double the existing dive profile and calculate deco time based on that. Shouldn't be terribly difficult in the software programming. Lots of potential features for cave diving that could be added to computers to help with planning cave dives
 
https://www.shearwater.com/products/perdix-ai/

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