Rebreather with a long hose

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Thanks. The concept, not my own, is full bailout onboard (Lp 50s or LP85s) with an AL80 of 50% and an AL40 or AL80 of O2 offboard. They plug in via schraeder or swagelock connection to the loop.

Interested in what you guys find out. I know there are divers on this forum that use this (or a standard) config.
 
So I think I'm envisioning a cave diving setup where the backup reg is on a short hose with a necklace, and the long hose tucks under your can light, wraps around your body and neck, and is clipped off to your right shoulder d-ring. Standard Hogarthian setup.

UTD (an agency I don't have any certification through, nor one I'm advocating for) shows their configuration as keeping the same setup (not sure about the short hose backup) and when you need to donate, you come off the loop and unwrap the long hose. This seems unnecessarily convoluted to me and if you forget to go to your BOV/DSV, you could get water in your loop.

I think RB80 configs used in cave diving also incorporate the long hose. So, I'm curious, if you use a Hogarthian-esque setup on your rebreather, how do you manage the long hose. Do you wrap it around your neck like UTD suggests? Do you just tuck it in your belt and clip off on your d-ring? Or something else like stow it on the tank?

Are you thinking of the GUE version of the JJ? It's hard to find details or photos about this online, and I haven't done this training, but I think that they ditch the offboard bailout in favor of two large de-inverted manifolded onboard dil tanks with regulators in the same place they would be on OC doubles. These act as your bailout gas supply. There is a smaller (3 L) O2 tank and possibly an argon dry suit tank. The only photo that I could find has a BOV but I guess if you weren't using one you would bungee a backup second stage and wrap/clip off the long hose from the right post (donation) reg.

Do they say that you need to wrap it around your neck and then come off the loop to deploy it? That seems slow and dangerous. Since your bailout in this configuration would come from your left post (BOV or necklace), you could just clip off the right post reg to your right shoulder D-ring (maybe with a breakaway), and tuck the long hose into your waist harness.
 
The JJs I have seen at Extreme Exposure had large off-board dilutant cylinders (valves by your head) connected by a lola manifold. But I just glanced at them in passing.

This is the best image I can find (these are not the JJs I saw in person):
9e4da0f3-b99e-4107-b64a-2b4b44fc9ea9.jpg


Here a list of parts that might be right: Building a GUE JJ CCR
 
The JJs I have seen at Extreme Exposure had large off-board dilutant cylinders (valves by your head) connected by a lola manifold. But I just glanced at them in passing.

This is the best image I can find (these are not the JJs I saw in person):


Here a list of parts that might be right: Building a GUE JJ CCR

Yup, that looks like it. The two large dil cylinders are on board, not offboard. It doesn't look like there is a dil MAV, the right post dil regulator just feeds the ADV in that posted build list.

Here's a description of a GUE CCR class: http://www.techdivenz.com/pdfs/articles/GUECCR020514.pdf

And here's another photo - doesn't show everything very well but you get the idea:

GUE_JJ.jpg
 
I do struggle to see the advantage of a long hose when using a rebreather - unless it is for an OC buddy and that would be a flawed team.
If the demand hose is for a rebreather buddy I don't see the logic.
The vast majority of rebreather faults are slow onset issues, generally you have time to analyse and resolve the issue. The possible exceptions to this is a torn/damaged loop hose and CO2 issues.
If you have an immediate issue you bailout to your own bailout.

As a rebreather diver, once off the loop you are on to independent stage cylinders. If you are doing 'team' bailout i.e. a very deep dive or a cave dive where each individual can't carry enough gas to individually bailout at the deepest(furthest) part of the dive and return to the surface with what they are carrying. Then you hand off cylinders to a member of the team when each cylinder reaches the 50% point and are handed a replacement.

The idea of mixing OC and CC divers on a dive that would require a long hose as an option is flawed. I am happy for someone to convince me that there is an advantage, but I cant see one as it stands.
 
Thanks for the pictures and docs guys. That is basically what I was looking for. I don't see a backup 2nd stage on a bungee necklace (BOV instead), but the long hose coming off the right post is still there. I think the use is for mixed teams where you may have to bail out an OC diver and go through a single-file restriction.

My recollection is that UTD trains to have the long hose around the neck still, but I don't get that setup. I could see it tucked into the belt and just clipped off though.
 
The idea of mixing OC and CC divers on a dive that would require a long hose as an option is flawed. I am happy for someone to convince me that there is an advantage, but I cant see one as it stands.

The advantage is when you don't have many CCR buddies but you still want to dive!
 
My recollection is that UTD trains to have the long hose around the neck still, but I don't get that setup. I could see it tucked into the belt and just clipped off though.

Maybe a UTD instructor can chime in. Long hose around the neck works great for primary donation on OC, duck your head and pass it off. I can't understand a recommendation for doing that while on a loop, seems very counter-intuitive.
 
After reading this thread I think GUE teaches the same.

RB80 Course Report

It did get me thinking about the post that feeds the BOV, and that it would be good to have another second stage on the other post if you had to shutdown the one with the BOV. So basically, each valve you carry should have a 2nd stage, to include off-board deco gasses.
 
remember that the RB80 is a sCR, so basically a gas extender. Very different than a CCR where the gas that you have on your back is unlikely to be breathable for long, especially at depth.

also remember that with these agencies, it is all team diving where the team is theoretically diving nominally identical gear. I.e. if you have to start sharing air with someone, you have had at least 2 major failures that have rendered your gas inaccessible. Not that likely to happen, and beyond what you would normally plan for.

All of the backmount CCR cave divers that I know that aren't diving with the GUE style rigs *i.e. the "normal" rigs with either o2/dil on the back, or dual O2 on the back and dilout on the sides* have at least one tank with a long hose on it on the off chance that some poor bugger needs help that isn't part of their team, but also on the offchance that you have to or choose to dive in a mixed team. Doesn't really change that much of the gear configuration, for anyone. These guys will usually have sidemount bailout and in this case, instead of the long hose doing a modified hog loop like it would in OC sidemount, it comes straight up and clips to the right shoulder d-ring with the left hand/short hose bottle going up in the normal suicide strap routing. Short hose is still "my hose" and is on the left, consistent with OC sidemount diving. Long hose is still on the right, arguably where it should be with a "normal" regulator so the hose doesn't cross under the diver in an OOA event, and is clipped off for easy deployment if it comes to that. If they have stages, the stage goes out first with the reg going to the diver and then the whole bottle. If they need more, then the long hose is available.

some of the sidemount CCR guys that I know largely have the breather on the left, and the right bottle is the normal long hose tank from sidemount configuration. They keep it clipped to their right shoulder d-ring. Kind of a **** picture, but this is Edd Sorenson in the Sidewinder which basically acts as a bmCCR with sidemount dilout. You can see the left bottle regulators in the "normal" routing that comes up around his neck and is on the necklace, and the long hose comes up and is clipped to the right D-ring. Others dive it with the breather on the right and a dilout bottle on the left and run the long hose on the left and clipped off to the right d-ring. Not as easy to access if you have to donate as just having it clipped off, but easier than in backmount because the loop hoses are only on one side so you don't have to remove the loop from your mouth, just reach above the hoses.

Pros and cons, but some of it is CCR specific in terms of where you put which bottles. I.e. SCR like the RB80 or CCR modded like the GUE JJ with two big ass drive/bailout bottles on your back, bmCCR with dil/o2 on your back where you really aren't going to be able to share gas out of a 2l/3l bottle for very long, bmCCR with dual O2 on your back and dilout bottles, or smCCR with one dilout bottle.
Some of it is determined by whether or not you are diving in mixed teams, either planned, or unexpectedly and would have to share out of your big bottles or you are diving with bottles that are easily passed. I.e. in an area where you only have AL80's, I would just as soon plan to pass them around like stage bottles than try to deal with a long hose.
Some is personal preference and what you figure out works for you and your buddies. It's been a big point of discussion for my dive team on how we want to handle it and we still haven't settled on how we're going to do it, but we know we need one for the warm fuzzies that it brings and will figure out how to manage it eventually
 

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