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ratown
05-01-2008, 21:30
Sorry if this is annoying to anyone, but I am just really curious. I was reading my Discover Mag cave diving article and I am just amazed at how far these guys go. How long can an experienced diver stay underwater with say 5 tanks (I'm not sure the size so let's say the cave standard) like one of the guys in the article? I can't believe how far these guys have gone, and I think it is way cool how they can analyze groundwater polution problems under there. The pictures were absolutely beautiful too.

fire diver
05-01-2008, 22:08
The guys making those incredible pushes are using rebreathers. You just can't get enough tanks to do the job. I believe many of them are carrying backup rebreathers as well.

in_cavediver
05-02-2008, 06:33
I can go for around 2-2.5 hours on my 104's with a single 80 stage at a depth of around 60-80ft max (three tanks). If you add higher flow, more exertion etc, the time drops. If you add more bottles, you start seeing a drop in gains based on the extra drag. Personally, 2 stages is the most I'd want to carry without a scooter and even then, its a pain. Mind you, this is following the rule of thirds so when I get out, I still have 1/3rd of my gas or in the case of 1 stage+backgas - around 123 cubic feet not used. (104's pumped to 3700, 80@3000)

Rebreathers though, they can really add the bottom time. JJ (of GUE fame) has done a few push dives over 24hrs in length with absurd depths and bottom times. I'll just say when a sport diver looks a saturation tables for deco information - its kinda on the edge. (think 6+ hours BT @ 300+ft depth).

For me, when I next make a major dive related purchase, it will be a CCR, likely an optima.

ratown
05-03-2008, 09:10
The guys making those incredible pushes are using rebreathers. You just can't get enough tanks to do the job. I believe many of them are carrying backup rebreathers as well.

They don't have rebreathers in this article. One guy had 5 tanks and the other had like 4.

ratown
05-03-2008, 09:13
Here is the article. Just scroll down to the bottom.

The Race to Find the World's Biggest Underwater Caves | Ocean | DISCOVER Magazine (http://discovermagazine.com/2008/apr/11-the-race-to-find-the-world.s-biggest-underwater-caves)

in_cavediver
05-04-2008, 07:56
What they are doing is connecting cenotes to each other and in the process, connecting cave systems to each other. You may be able to do a single dive and connect two 30,000+ft cave systems together but you dive might only be 2000-4000ft of penetration.

Dive-aholic
05-04-2008, 11:37
The caves in Mexico are different than the ones in Florida. While in Florida it may be several miles before you find another opening to the same system (Peacock is the one exception I can think of), in Mexico it is very common to swim past several cenotes on a single cave dive.

ratown
05-08-2008, 10:06
The caves in Mexico are different than the ones in Florida. While in Florida it may be several miles before you find another opening to the same system (Peacock is the one exception I can think of), in Mexico it is very common to swim past several cenotes on a single cave dive.

Ohhhhhh. Thanks.

wolfen42
05-08-2008, 11:01
It seems almost comical to read about the sheer amount of distance covered and time spent on some of these dives at this point in my diving career (thoroughly no-deco rec)... 24 hours under? Boggle....

Murloc
05-08-2008, 16:02
It seems almost comical to read about the sheer amount of distance covered and time spent on some of these dives at this point in my diving career (thoroughly no-deco rec)... 24 hours under? Boggle....


and of course they don't pee in their wetsuits either :smiley2:

ianr33
05-08-2008, 16:50
It seems almost comical to read about the sheer amount of distance covered and time spent on some of these dives at this point in my diving career (thoroughly no-deco rec)... 24 hours under? Boggle....

Yep,not many people would ever do this
YouTube - WKPP: Turner Sink-Wakulla Springs Connection Dive, 7/28/07 (http://www.youtube.com/watch?v=A0nNXAB6_kE)

7 hours at 300 feet is not exactly a trivial dive !
Turner - Wakulla Traverse | Global Underwater Explorers (http://www.gue.com/?q=en/node/393)

in_cavediver
05-08-2008, 16:50
It seems almost comical to read about the sheer amount of distance covered and time spent on some of these dives at this point in my diving career (thoroughly no-deco rec)... 24 hours under? Boggle....


and of course they don't pee in their wetsuits either :smiley2:

Nope - They dive dry with a P-Valve......

WaterRat
05-09-2008, 17:18
Not to mention that much of the cave system in Mexico has a max depth of around 40 feet. This makes the gas last a lot longer than the 300 foot depths they hit in Florida. YOu also have very long NDL limits at the shallow depth.

Ron

Mtrewyn
05-09-2008, 21:12
Not to mention that much of the cave system in Mexico has a max depth of around 40 feet. This makes the gas last a lot longer than the 300 foot depths they hit in Florida. YOu also have very long NDL limits at the shallow depth.

Ron

So what are the limits at this depth? If air was not an issue.

Dive-aholic
05-11-2008, 21:31
Well, a safety stop is done at 20'. So if you're diving at an average depth of 20', which many of the caves in Mexico are, you're basically just doing a really long safety stop.