¿QUÉ ES LO MAS EXTRAÑO QUE HAN VIVIFO DURANTE EXPEDICIÓN?

Not the prettiest, but quite a fun dive with this little visibility!

I'm looking to do TDI full cave and TDI stage cave somewhere next year. But I'm already trying to find a dive center, I'm located in Europe so was hoping someone here has experience with any of the dive centers in Mexico to do these courses.

The salinity, density, flow, and temperature all conspire to create the halocline. It’s the stratified interface where the freshwater of the underground rivers of the Yucatán sits on top of the intrusion of the Gulf/Caribbean directly into the peninsula.

It is a little hard to film, to convey the real experience of what swimming (or scootering) through the thin, blurry layer really feels like.

This video gives some vague impression, at least, of what it feels like when you’re trying to hold a video light in the same hand you’re driving the scooter with and holding a GoPro out at an arm’s length with the other hand.

I've been developing an interest in understanding cave divers and the caves they choose to explore. Although there can be some extreme cases, I find this hobby/interest as something I never thought of before.

I'm curious to know how did this interest develop? What led you to believe that it's something you'll want to explore? And are you scared of the unforseen events that might take place?

OC trimix 13/47 with DPV in the downstream section of Eagles Nest Cave in Hernando Florida USA. Went through the pit to the deep section. Depth after the pit was 292ffw. Air as travel and deep deco, 46% mid deco, and 100% 20ft and 10ft deco. Total run time 2:06:25. Such a fun dive!

Hi all, Cave Crave's game director here.

We're currently creating a VR journey through Tham Luang, including cave diving sections. Thanks to the support of LiDAR expert Richard Walters and caver Vern Unsworth—the latter having been directly involved in the 2018 rescue operation—we're working to make the experience as authentic as possible.

As with our recreation of Nutty Putty Cave last year, our goal isn't to gamify a real events, but rather to faithfully recreate the cave and help players understand some of the physical challenges faced by the rescue team.

Coming to all major VR platforms this July.
If you have any questions, feel free to ask!

Piotr

This whole tragedy is extremely confusing to me. So much so that I wonder if something weird could have happened involving currents, some type of sudden in-the-moment confusion from nitrogen narcosis, or ...?? I have never scuba dived but over my life I've seen and read stories/videos about how dangerous cave diving is, even for those with proper training. It's obviously very, very very very VERY VERY VVVEEERRRYYY dangerous.

Even I know that it's fundamentally suicide to enter a cave without a) a guideline, b) proper equipment, and c) training. ALL THREE OF THESE!! And this knowledge is just from basically being a regular person for 50+ years. Just like I know you don't drive a car while blindfolded, you don't parachute without a backup chute, you don't rock climb without protection, etc. These things are so incredibly, fundamentally, in-your-face obvious that the only people who go against them are a small handful of thrill-seekers or one-of-a-kind experts like Alex Honnold or Dean Potter.

So my question is, why did all 5 of these seemingly smart, experienced, healthy people decide and agree to do something that violated ALL THREE of the things listed above (guideline, equipment, training)??? WHY?? It makes no sense! Why would they do something where the chance of DYING was OBVIOUSLY at least 10-20-30-40-50%? Even 5% if they somehow thought it was that low?

I'm asking a serious question here. They all said, "Hey, let's dive down and swim into a cave where normally when you even reach the depth of the entrance, you have to turn around and go back up or risk running out of air / the bends. But instead of going down and immediately back up, without entering, we'll go INTO the cave and swim around for a bit. Sound good? OK, great, let's do it." And they all agreed that made sense, and then actually continued to think it made sense, and literally went down and literally continued to think it made sense, and literally SWAM INTO A CAVE WITHOUT A GUIDELINE OR TRAINING OR ENOUGH AIR.

Is it possible there is another explanation for how they ended up in there? Sucked in by some current, for example?

I've seen people saying that you have to have humans explore underwater caves because 'a drone would get tangled and then you'd need a human to go retrieve it'

But, as with the drones used in Ukraine, if you put the spool on the drone itself, it's impossible to get tangled or stuck. The drones in Ukraine can fly between trees in a forest and into buildings no problem.

So if you built an underwater drone with a spool of fibre optic cable on the drone itself, then you could explore any underwater cave with it and it wont get tangled.

Thoughts?

Hi all, I'm a Tec Instructor continuing a journey of self improvement, I'm looking for recommendations for full cave training in Asia. I'd love to go back to Tulum and train in the Cenotes, where I fell in love with the caves 10 years ago, it took me a while to improve myself until I feel ready to learn how to dive them properly, but going there is not a possibility right now.
So, what are reddit's recommendations for instructors? Indonesia, Philippines, Thailand, Malasia or anywhere in Asia really.
Thanks a lot.

Can anyone recommend any good educational documentaries on cave diving? Thanks

One of the two guys on that ill-fated Maldives splunk was apparently a diving instructor ...

Super excited after doing some side mount diving in the caverns in Tulum last summer I’ve finally booked my Intro to Cave. Super excited to start this step! Didn’t really have anyone who “gets” it so figured I’d post here. Any advice I’d be happy to read but just wanted to share my excitement.

Wanna argue about CCRs? Cool! I post this here, in the Cave Reddit because it’s a somewhat cave-specific answer to a few CCR questions.

As a full-time instructor the answer I just wrote to one email covers a couple idea I seem to keep discussing with folks time and again. These are, for our area, in any case, the two most popular current configurations of CCR, and for good reason.

A few caveats to this response: I was asked about a few specific models, so the answer addresses those and it disregards backmounted models entirely. Not because they should be discounted, just because it wasn’t part of the question.

Also, I have no professional relationship with any of the mentioned manufacturers and am not endorsing or mudslinging any of them, simply acknowledging their existence and that they all have pros and cons.

For those of you who are going to tell me I’m an idiot for holding these opinions: I already know that.

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“Rebreathers. Yeah, EVERYONE has got opinions. And usually that opinion is, “Mine is the best there is and you should get one, too, and all other rebreathers are dumb.” I think people have to say that to justify the expense to themselves.

I’ve got a LOT of thoughts. Many of them seemingly contradictory. Mostly because, as you’re certain to find shortly, there isn’t really a “perfect” rebreather; they all have their benefits and drawbacks. A lot of it comes from the type of diving you’ll be doing and, possibly even more, personal preference. Definitely try a few and start getting a feeling for them, but I am sorry to say that it’s going to be very, very hard to know what you like and what you don’t until after you’ve been diving on the bloody thing for a few months.

My very first thoughts that are worth mention is that I’m not wild about chest-mounted units such as the Triton or the Symbios.

Two main reasons are Work of Breathing and dive profile.

WOB……. Think about pressure deltas, the difference in pressure in the water column; obviously the deeper you go, the higher the pressure. The delta between the counter-lung and your actual lungs being one of the key components that affects WOB on a CCR. With chest-mounted units, the counterlung is at least 15-20cm deeper than your actual lungs, which doesn’t sound like a lot. But it’s enough that your diaphragm, which usually relaxes as you exhale, actually has to work a little bit to inflate the counterlungs like blowing up a very easy balloon. But blowing up a balloon on every single breath for potentially hours. Will you notice it? Probably not. But your body will.

Then there’s the profile. Instead of a slipstreamed SM profile you have this thing on your belly. Might as well dive backmount for as much as it increases your profile. And I see a LOT of Choptima, Triton, and Symbios-shaped gouges in the silt.

All that needs to be read with a bit of a grain of salt, considering my prejudice against them. There are loads of people who love them and hundreds of safe dives made on them every day. The Symbios especially has a bunch of recent fans, and for good enough reasons as it’s got a couple of really cool features. And as far as packing….. yeah, they’re little and pretty flexible in terms of configuration (can be used with SM, BM, or even a single). Hell, if you were in the Carribean you could clip it to your belly, sling a AL40, and call it a day. Which is neat.

A long answer to a fairly simple question, huh?

Now on to the next one. Which is, I’m afraid, an equally long answer. mCCR vs eCCR

This, too, depends on where you’re looking to dive. And the short version is:
Here: manual without question
Pretty nearly anywhere else: either
Reason being depth changes.

On an eCCR you’ve got the electronics and the solenoid trying to maintain a set PPO2 at all times. Which is amazing when you’re bobbing around at 60 plus meters; any depth changes doesn’t really affect the PO2 too much because the ambient pressure difference between 60m and 55m is almost negligable. So if you ascend a little bit the solenoid doesn’t have much, if any, work to do.

The ambient pressure difference as you follow the contours of the caves here from 10m to 5m is HUGE. As you make that ascent a couple of things happen:
All the gas spaces on you expand quite a bit. Your drysuit, your wing, and your loop volume. The drysuit and the wing are easy enough to deal with. As, generally, is the loop volume. BUT, the solenoid starts to fire, too as the loop volume expands; because as it’s expanding, the PO2 is dropping, too. So now you’ve got this expanding loop, that is also getting filled with O2 which expands it more, that you need to vent to maintain buoyancy, which wastes O2. Now do that for a few hours. It’s a pain in the ass.

It’s a big enough pain in the ass that I pulled the solenoid out of my eCCR, turning it into an mCCR.

If I were diving elsewhere, I’d put the solenoid back in and let the electronics drive it. Especially if I had rapid descents to real depth, that’s where an eCCR really shines. This is, however, mostly because I’m lazy, not because I prefer or trust electronics.

On the whole, I tend to be more inclined towards manuals. They’re more flexible in my experience more reliable and predictable, and they’re just as easy to fly as an electronic. So lots of positives, with the only drawback being you have to pay a little more attention (but is that really even a drawback?)

More precisely, they’re not truly manual, but rather CMF CCRs. Constant Mass Flow, that have a “leaky valve” like the entire KISS line.

As to what I value most in a unit? Ease of diving and streamlined operation.

All that said, of the ones mentioned, if I were you and was going to buy one today? The Sidewinder. The original one. A used one for cheap as a first unit. In all honestly, I have been passively thinking about getting one of them myself for a while.

Not only is the Sidewinder 2 now out with some cool features, also worth consideration is the Fathom Gemini. Same ideas, some awesome philosophies built into it. Not superior/inferior, just different.

One nice thing about the configuration of what we can call Sidewinder-style CCRs…. The counterlungs wrap around your body at the exact same depth as your actual lungs. The WOB is almost exactly the same as you sitting there now, reading this in almost any body position in the water.

Another neat thing is that, if you ever have a problem with the rebreather on the surface, you unclip two bolt snaps, put the rebreather back in the bin, and then you go for a SM dive instead. The style does have its drawbacks, just like every configuration, but has some pretty big benefits.”

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Cutting off there as the rest of the email to our guest doesn’t concern you (you nosy bastards). And besides, I figure there’s already enough in there to get everyone worked into a lather about how I don’t know what I’m talking about.

I had the pleasure of sitting down with Jill recently for a long conversation. I knew her reputation going in but nothing quite prepared me for how direct she was about the reality of what she does.

The death rehearsal protocol stopped me. Before every dive she sits at the surface and works through every possible way she could die that day. Methodically. Calmly. She doesn’t see it as morbid. She sees it as the only honest way to enter the water.

She’s lost more than 100 friends to cave diving. She talked about that too, what it costs, what it teaches, and why she’s still in the water.

The iceberg dive in Antarctica. Swimming three kilometres inside the Earth with no way to surface.

The moment she knew the Toronto ad agency life was over when she hid from her own client at the airport.

This is the most honest conversation I’ve had about what this world actually demands of the people in it.

Full conversation: https://youtu.be/XDO_x5VSm8o?si=vMANvE3rXJIJr_4Z