What's with the UTD haters?

[rhwestfall]

yeah, but where would we be without "it could"?

 

[Kevrumbo]

Well . . .to be fair --there is one possible incident that I heard of which might be related to the QC6 female connector supplying an O2 or Diluent injector add/button block on an UTD MX Rebreather. Plugging in deco mixes via a QC6 male while underwater might inadvertently squirt water as well into the block --and especially if seawater-- the salt crystals could jam-up/clog or seize-open the shrader valve mechanism.

The preventative action is of course to regularly clean & overhaul critical components as part of an annual maintenance schedule. As it applies to a simple Z-system Distribution Block or IsoFold (i.e. no injector button blocks used), simply an ultrasonic bath, clean, dry & inspect. . .

 

[SanDiegoSidemount]

Well . . .to be fair --there is one possible incident that I heard of which might be related to the QC6 female connector supplying an O2 or Dil injector block on an UTD MX Rebreather. Plugging in deco mixes via a QC6 male while underwater might inadvertently inject water as well into the block --and especially if seawater-- the salt crystals could jam-up/clog or seize-open the shrader valve mechanism.

The preventative action is of course to regularly clean & overhaul critical components as part of an annual maintenance schedule. As it applies to a Z-system Distribution Block or IsoFold, simply an ultrasonic bath, clean, dry & inspect. . .

I was having a conversation just this morning with AG's "shop man" Jay about this issue. I was trained "old school" regarding regulator care, taught to pay fanatical attention to keeping regulator internals clean and clear of sea water. So I've had my concerns about the QC-6 connection and the small amounts of water it can admit into the LP system.

He said he had never seen any failures of manifolds or second stages attributable to water intrusion via the QC-6. In his experience, annual inspection and cleaning seemed to be enough to keep it all working just fine.

 

[Kevrumbo]

In sidemount Z-system, the virtue of the distribution block [or the new isofold/manifold] is that you never have to switch out regs as you alternate breathing off of left & right tanks --i.e. alternating between shutting down one tank valve and opening the other in Z-system sidemount diving, you are always breathing the primary long hose regulator.

With the above in mind, here is the simple process of switching tanks on Z-sidemount to trim balance them, while on-the-fly-scootering (Right Tank currently open to start):

--Turn on Left Tank valve with your left hand;
--Take your left hand and replace your right hand that was operating the scooter trigger, continue trigger operation with left hand;
--Turn off your Right Tank with your right hand.
--Replace left hand trigger with your right hand as needed. . .

No exchanging one regulator for the other as you would have to do if you were diving conventionally independent, normally open tank valve sidemount gas cylinders each with its own regulator & second stage. It would be inconvenient to say the least, to exchange & stow a regulator while scootering on-the-fly, and then have that just stowed 2nd Stage Reg start free-flowing (you probably would have to had previously installed an Omni in-line shut-off valve so as to prevent free-flow on that unused stowed regulator while on-trigger scootering with conventional independent doubles & regs anyway). . .

Again, Fundamental long hose DIR/Hogarthian technique has you ALWAYS breathing the long hose primary regulator on bottom mix, unless you've just donated to an out-of-gas buddy --that's the best practice Scuba Diving paradigm I first learned ten years ago and still choose to retain. Contingency training with the "added complexity" of the QC6 connectors [Z-distribution block or Z-isofold/manifold] is not hard to accommodate at all and can be learned like any new novel skill, technique & task.

Development & reasons for the Z-system from Andrew Georgitsis of UTD:

. . .However, all this banter about "failure" points [of the Distribution Block], detracts from the core and central issue, which is, if you want a system that is consistent with your previous, current or future Hogarthian/DIR/UTD training and skills, that is scalable from single tank to mCCR rebreather, that is capable of mixed team diving, that has interchangeable components and that also allows you to configure and dive a configuration that is best suited for your diving or exploration needs, then the Z-System is the only one that is capable of that.

I carry both conventional BP/W and the Z-system sidemount while traveling, because I still elect to keep the long hose paradigm & protocol to be consistent between Backmount & Sidemount. I am confident in my previous & current training to handle the extra "failure points" of both conventional manifolded twinsets as well as the new doubles sidemount Z-system. In Truk Lagoon, I dive backmount 11L doubles & deco bottles on the deeper wrecks 45m & greater in the morning, and use Z-sidemount in the afternoon on the shallower wrecks. Either way, I'm compatible with my Truk Dive Guide who uses DIR/Hogarth long hose configuration with backmount doubles.

(And btw, how ironic that the Halcyon Contour sidemount harness does not support the Z distribution block or Z Isofold, both of which allows and provides the compatibility for the basic Long Hose Paradigm -the best Diving Practice so promoted by GUE for these many years now?)

Finally as an aside, here's an overview example of how the UTD concept of a mixed-team works in general for exploration wreck diving on a large ship:

You have the CCR divers be the "Pathfinder Team" --lay a reel-line on a long traverse from bow to stern and designate that as a working Mainline. Then you have other divers in backmount & sidemount doubles go explore other places in the superstructure by running spool guide lines off the Mainline (i.g. crew's quarters, cargo holds, engine room, Bridge etc), or take pictures/video with a member of the Pathfinder Team on CCR guiding as needed. Then after a week's time or so exploring, you have the Pathfinder CCR divers go in and reel-in/clean-up the Mainline. . . (That would've been the plan in Bikini Atoll on the 900'/270m long USS Saratoga Aircraft Carrier last June --except now the Flight Deck has collapsed & pancaked most of the underlying airplanes & weapons/ordnance on the Hangar Deck, from the Bridge/Island to the stern).

 

[bluemed]

As a UTD Instructor the only thing I can say is that I am happy to be part of a progressive, innovating and dynamic agency.
Yes, maybe some things can be done in another way, but that is a part of an agency like this, people are always looking into new things.
The playbook, a collection of all the protocols, how to teach, what to use etc.. is a piece of art, everything is in there...NO more, maybe you can do it like this and tomorrow like that, the thing I had with the former 2 agencies I was teaching for.
There is no comparison , no agency has a tool like the playbook for instructors.
Like it or not, but one thing is for sure..it is highly likely that UTD divers and Instructors are divers above average, it is because of something...that for me is enough ;-)
like some people posted here already..come and have look gor yourself, we don't bite ;-)

 

[gearhound]

AG has developed and been using the QC6/block manifold system since 1996 and the first Wakulla push beyond 10k linear feet to 14k, on the big old "fridge" PSCR/Pre-RB80 rebreather: no problems with "failure points" back then . . .and none that I've heard about or experienced at all while using the Z-sidemount system.

And people have been diving side mount with independent cylinders since the 70s and pushed a lot more linear feet of cave. UTD didn't get into side mount until 2010 after two UTD instructors took a course from Bogaerts. That's a fantastic place to get training and I do not doubt anyone's skills. But you're pointing out history.

One of the benefits of side mount is that it puts everything within sight for dealing with issues. The manifold puts it behind my back again. Didn't it just reintroduce the "9 Failures"? Any way Kev, since you like pointing out all the wonderful places you can take your system, I can dive the same places with my regular side mount system. I, however would not take the manifold into the caves that I dive. So, which system is more universal?

 

[Kevrumbo]

And people have been diving side mount with independent cylinders since the 70s and pushed a lot more linear feet of cave. UTD didn't get into side mount until 2010 after two UTD instructors took a course from Bogaerts. That's a fantastic place to get training and I do not doubt anyone's skills. But you're pointing out history.

One of the benefits of side mount is that it puts everything within sight for dealing with issues. The manifold puts it behind my back again. Didn't it just reintroduce the "9 Failures"? Any way Kev, since you like pointing out all the wonderful places you can take your system, I can dive the same places with my regular side mount system. I, however would not take the manifold into the caves that I dive. So, which system is more universal?

If your objective is universality and the ability to muck about solo (or in a "coincidental ad-hoc dive team") in the deepest darkest tightest crawlspaces in some sump, then Z-system is probably not applicable to you. . .

Z-sidemount system is a solution -albeit more complex and diverging from orthodox DIR and even conventional independent doubles sidemount practice- for those divers like myself who dive with mixed international UTD/GUE teams (btw -always using the metric system), and elect to keep fundamental long hose diving paradigm, technique & protocol . . . other than learning the new mechanics of QC6 connections and alternating independent tank switching & gas management, all my previous base knowledge, training and diving experience in long hose tech/deco/wreck overhead was perfectly consistent --quickly, seamlessly, and intuitively applied. . .

And what's the reluctance about utilizing the 9 Failures Problem Solving Model for gas flow checks that we all fundamentally learned in Intro to Tech Diving/conventional backmount doubles?

Here's a comparison of backmount vs Z-sidemount flow check drills:

A very cursory review of the 9 Failures Heuristic/Problem Solving Model:

For conventional backmount manifolded doubles, the two main objectives are: Determine which side the failure/leak/malfunction is actually occurring, and whether it is due to a post failure or a manifold failure.

The 9 Failures are inductively simplified as follows:
Right Post Failures: Either Fixable (#1) or Non-Fixable (#2).
Right Side Failure in general vicinity of Manifold Crossover to Isolator Knob (#3).

Left Post Failures: Either Fixable (#4) or Non-Fixable (#5)
Left Side Failure in general vicinity of Manifold Crossover to Isolator Knob (#6).

Mistakenly perceiving the Failure on the Right Side, when it's really on the Left (#7).
Mistakenly perceiving the Failure on the Left Side, when it's really on the Right (#8).

Manifold Valve broken/leaking or absolutely have no idea where the Failure is . . .(#9)

--
Similarly for Z-sidemount with the Isofold:

Right Regulator Failures: Either Fixable (#1) or Non-Fixable (#2).
Right Side Failure in general vicinity of Hose connection to Isofold (#3).

Left Regulator Failures: Either Fixable (#4) or Non-Fixable (#5).
Left Side Failure in general vicinity of Hose connection to Isofold (#6).

Right Tank Valve Failure (#7) or Left Tank Valve Failure (#8);
and Z-system gas delivery interruption (#9).

QC6 connection/disconnection scenarios & options are also part of the problem solving outline above for Z-sidemount with Isofold. To recap for Z-Isofold: If you hear bubbles, open both tank valves and isolate; if no bubbles but you have breathing gas interruption -then open both tank valves but do not isolate. In each case go through your 9 Failure heuristics and do final flow checks upon solving the problem. (Also you're supposed to be with teammates as well --ask for their help or long hose donation as needed if the problem cannot be solved).

 

[wedivebc]

Then there is independent side mount:

A very cursory review of the 9 Failures Heuristic/Problem Solving Model:

For conventional backmount manifolded doubles, the two main objectives are: Determine which side the failure/leak/malfunction is actually occurring, and whether it is due to a post failure or a manifold failure.

The 9 Failures are inductively simplified as follows:
Right Post Failures: Either Fixable (#1) or Non-Fixable (#2). (#1) Non Issue or (#2) Non Issue
Right Side Failure in general vicinity of Manifold Crossover to Isolator Knob (#3). (#3) Non Issue

Left Post Failures: Either Fixable (#4) or Non-Fixable (#5) (#4) Non Issue or (#5) Non Issue
Left Side Failure in general vicinity of Manifold Crossover to Isolator Knob (#6).(#6) Non Issue

Mistakenly perceiving the Failure on the Right Side, when it's really on the Left (#7) (#7) Non Issue
Mistakenly perceiving the Failure on the Left Side, when it's really on the Right (#8) (#8) Non Issue

Manifold Valve broken/leaking or absolutely have no idea where the Failure is . . .(#9) (#9) Non Issue

-QC6 connection/disconnection scenarios & options are also part of the problem solving outline above for Z-sidemount with Isofold. To recap for Z-Isofold: If you hear bubbles, open both tank valves and isolate; if no bubbles but you have breathing gas interruption -then open both tank valves but do not isolate. In each case go through your 9 Failure heuristics and do final flow checks upon solving the problem. (Also you're supposed to be with teammates as well --ask for their help or long hose donation as needed if the problem cannot be solved).

Or you could just learn how to switch regs like they teach in a PADI OW class and none of this is even an issue

 

[Kevrumbo]

Then there is independent side mount:



Or you could just learn how to switch regs like they teach in a PADI OW class and none of this is even an issue

And this is also where IMO the UTD Z-system sidemount trumps all: by virtue of that Distribution Block or Isofold/Maniifold, I can access and combine both available remaining tank volumes in a primary long-hose donation to an Out-of-Gas Buddy.

All my RockBottom/Modified Thirds gas calculations are valid, consistent & applicable between both my conventional manifolded backmount doubles and Z-system sidemount doubles diving on Alu 11L cylinders (AL80's). . .

 

[gearhound]

Umm...I'm pretty sure I can access the air from both of my tanks without the use of a manifold. So I see no need to spend the extra $1000. Nothing prevents me from donating to an OOA diver in back mount or CCR with a long hose if I have to. I can even do it without having to worry about turning valves on and off, so a lot less task loading, and a lot more like traditional back mount.

I'm not sure why you think your dive team is more valid than my "ad-hoc" dive team.
And the places I dive are both challenging and beautiful! So I'm not sure why you're insulting where I like to dive. But it just might answer the original question that SanDiegoSidemount asked.