Rebreather designs and buoyancy control strategies

[oya]

With all due respect, what have you contributed?

Try giving. It feels good.

I like to call BS when I see it.

So that when newer, more impressionable divers see things from self-proclaimed experts there is at least someone there planting the seed of doubt. So they don't think they have to aspire to control their buoyancy with overfilled counterlungs or to practice swimming around without monitoring their own PO2.

 

[oya]

Ego's jousting.

Would be nice to keep the thread on topic and really see would could be learned.

Is there much more to know about the accident?

The instructor certainly won't talk (or, possibly, wasn't even there).

There are a few strong theories which have been proposed, most of which go back to lack of training and experience.

So... get trained properly, build experience slowly. And don't do 3 trimix dives in a day.

 

[mdb]

The "duty expert"( -Rebreather pilot speaks again.

Let the thread continue.

 

[mdb]

Has Re breather diving now become the new "Tech"?

 

[St John the Diver]

I like to call BS when I see it.

So that when newer, more impressionable divers see things from self-proclaimed experts there is at least someone there planting the seed of doubt. So they don't think they have to aspire to control their buoyancy with overfilled counterlungs or to practice swimming around without monitoring their own PO2.

It's funny: when Will Smithers came up with the breath-counting method of blind CCR escape he was engaged in developing procedures for getting out of caves that reduced bailout consumption. At that time just about every diver diving a rebreather knew this method, understood it, and carried it as a tool in their intellectual toolbox.

You were only eleven years old when he published it on the old NWD rebreather list (back when the only internet was email and Usenet) and you don't have any memory of it. Nor were to around when it was tested and proven to work. So: You don't know what you don't know, and you don't know this. Rebreather diving wasn't invented yesterday. There's lots still for you to learn. Do you know, for example, that we used to support two divers in an emergency on one Mark-15? Yup: The standard military setup had two loops on one rig. The shoulder connectors had T-Pieces with two breathing hose sets installed. There was one for the diver and another laying secured on the back of the rig in Velcro straps ready for another diver to grab it. That's how the Army taught bailout for 20 years. It works. I don't think the Navy ever dived them that way, but still: there are methods that you've never even considered.

Maybe it's time to start learning again, rather than to think you know it all? I hope that I've not even begun to learn all that there is to know about diving.

 

[oya]

Yes, yes.

You're very clever and experienced.

But I'm not going to really be able to learn anything until there's a Mig 15 reference used.

 

[St John the Diver]

Yes, yes.

You're very clever and experienced.

But I'm not going to really be able to learn anything until there's a Mig 15 reference used.

Meg-15 is a bit newer than the rig I'm diving, and not sure how it's connected to this thread. Haven't even seen one.

 

[oya]

Mig

 

[rjack321]

The point about the gag strap is that it is rEvo's solution to the flooding issue, above or below the surface. .

Do you dive a CCR at all? Revo or something else? With a gag strap?

(gag straps are not there to protect you from losing the DSV and sinking on the surface - and in this case we don't even know if Rob was conscious or not when the DSV came out of his mouth)

 

[RichardC]

Do you dive a CCR at all? Revo or something else? With a gag strap?

(gag straps are not there to protect you from losing the DSV and sinking on the surface - and in this case we don't even know if Rob was conscious or not when the DSV came out of his mouth)

Yes I dive a rEvo and have for several years and yes I use the gag strap, always. I keep it on till I'm on deck, why take it off?

So, in my case it might well prevent me from losing my DSV underwater or on the surface. Why the skepticism?

As for whether they are intended to prevent the DSV coming out of your mouth on the surface? Well they are there to prevent the DSV coming out of your mouth, period. The surface is no different.

In practice I sit on deck breathing pure O2 for 10 minutes or so after getting out and I release the gag strap when I get comfy and get my dry gloves off.

To your second point; no we don't know if he was conscious when the DSV came out, but if he took it out as a deliberate action and didn't close it, that might be down to inexperience or to being partly incapacitated.