Eagle's Nest Abyss Room

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We have different definitions of "reasonable".
 
I've got a long hose attached to my right post. Come off the loop, donate, back on the loop. It's surprisingly fast, but it sounds like baloney.

.

Your system of the RB I think would be very easy,but what do you do for their donation to you,since I couldn't see a lot of detail but not sure if I saw dual long hoses on the sidemount bailout. I find this interesting because I understand the rationale for team diving performed by the WKPP,and everyone using same configurations,but now you are seeing a mixture. In the past the WKPP has had protocols for everything and practiced these as a team,but I see different elements there.
 
Tons of options.
If you lose breather, then bailout to OC.
If you lose a reg or bottle, then isolate and run breather off of good side.

Now for fantasy land scenarios
If you lose breather and OC, then go to donated long house from sidemount guy.
If you lose all OC gas, then you go on donated long hose from sidemount guys, or plug your breather into donated OC via QC6 plug.

Same goes if sidemount guy has failures, gets gas from backmount guy.

Also, these aren't your average divers!

Your system of the RB I think would be very easy,but what do you do for their donation to you,since I couldn't see a lot of detail but not sure if I saw dual long hoses on the sidemount bailout. I find this interesting because I understand the rationale for team diving performed by the WKPP,and everyone using same configurations,but now you are seeing a mixture. In the past the WKPP has had protocols for everything and practiced these as a team,but I see different elements there.
 
What an awesome video...but after watching I'm pretty sure cave diving is not for me. I got claustrophobic just watching, lol. I'll stick to the OW and pretty fishes.
 
Your system of the RB I think would be very easy,but what do you do for their donation to you,since I couldn't see a lot of detail but not sure if I saw dual long hoses on the sidemount bailout. I find this interesting because I understand the rationale for team diving performed by the WKPP,and everyone using same configurations,but now you are seeing a mixture. In the past the WKPP has had protocols for everything and practiced these as a team,but I see different elements there.

this is a bit of the problem with mixed teams. also this isn't a wkpp dive, just for giggles with aj brett and andy.


BUT it's extremely difficult for me to envision a scenario where aj would be out of gas and need a donation. he could lose all of his backgas (both posts or a manifold failure) and still drive the rebreather from the stage bottle. the stage is in effect 640 cuft of gas he can use to get 2000' to his first gas switch
 
They each have a long hose. If were close to the door it's share, tow and go. A little more distance and I'd take one of their bottles since a 120 is such a large volume of gas.

But for me to be out of gas, if have to lose the rb plus two regulators. That's a lot of junk to break on such a short bottom time.

On proper Wkpp rebreather dives (which this isn't, it's 3 friends going for a dive) we only use stage bottles.

---------- Post added January 27th, 2015 at 10:18 AM ----------

Also they have qc6s on all their tanks so I could plug one of them into my rb and be in business.

Lots of options.
 
How do you decide how much bailout to take on a dive like that? I mean, the OC gas requirements for that much time at that depth are pretty significant.
 
If you run the numbers the ride out from 2k at 270' deep isn't as much as you would expect

all of these divers are carrying two overfilled lp120s each. They have oodles of open circuit gas
 
There are a few ways to think about gas planning. One way is that you can think about where you want to go and how much bailout you need to get out if the RB fails, and another is how much gas you have and how much of that you can use.

So for the first option, say I want to go to 2000ft scootering. That'll take a little less than 20mins, so I need 20mins of OC gas to get out, plus a little for conservatism.

The other way uses the RB80 ratio to derive how much gas you can use. Its an 8:1 machine in practice, so you can use about 1/9 of your total gas supply to go in, allowing 8/9 (8x your ingoing gas) to get out on OC. You can fiddle with the numbers to increase conservatism of course.

If you plug in the numbers, 270' at a .6 SAC is like 5.5cuft/min. With the RB, its like breathing .6-.7cuft/min while 270. Neat, right? 1/9 of 324cuft (lp120s overfilled to 3600) is 36cuft. At a .6, 36cuft is like an hour of gas. By the numbers, you could penetrate for nearly an HOUR at 270' with the lp120s. Would I do that? No, absolutely not. But you could and still have enough OC gas to get out. For a dive like that I'd take an al80 drive bottle and probably an extra as a safety.

For deco gas you really just need 1x the OC amount.

---------- Post added January 27th, 2015 at 01:34 PM ----------

I should include that it took us 20mins to get to 2k because we had 3 restrictions and some line work to deal with. Without that its like a 15min thing to get to 2k.
 
https://www.shearwater.com/products/peregrine/
http://cavediveflorida.com/Rum_House.htm

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