DIR and SPG

[nadwidny]

Flow checks I (hope) i can handle, it's the rest

Make sure you know your 9 failures and their responses down cold. It'll make the week go smoother.

 

[Kevrumbo]

Check your Team, note your surrounding Environment, check your Kit (flow check, SPG check etc.) --proceed to lay Reel Line.
Check your Team, note your surrounding Environment, check your Kit --admire the stalagmite/stalactite formations.
Check your Team, note your surrounding Environment, check your Kit --look at the weird nudibranch thing on the rock.

React to and problem solve whatever contigency arises, and just as important, quickly locate the Main Line during an emergency situation and get to it IMMEDIATELY. You may have to for example, shut down a post, emergency signal your teammates and find/grab the Main Line with the correct direction orientation for egress --all at the same time-- before an ensuing silt-out occludes sight of everything. . .

Nick, you've been taught by one of the best Tech Instructors out there, Gideon Liew (AG's protege), and have received sound, practical and realistic training . . .You'll do pretty good!

 

[Kendall Raine]

A gas-sharing egress at nearly the furthest point of penetration, followed by a total light failure for the 3-man team is one of the most difficult & arduous drills to perform in an overhead class. However unlikely and improbable this occurrence may happen for real, the Drill illustrated an obvious point for me: everyone's gotta know how much gas that initial donor has. You have proper gas management and rock bottom reserve so at least you have a basic idea --how hard is it to just confirm it with a quick show of the SPG (right before the cascade of primary & secondary light failures in this Drill begins)? Also, a lights-out gas sharing egress in total darkness can take almost twice as long to effect an exit. A donor switch in this situation may therefore be inevitable.

Be consistent in practice, be prepared for the worst possible contingency. Always show your SPG on any Gas-Sharing Drill. . .

Kev:

Did they cover what you do if the total light failure happens first and then a diver goes OOG in a three man team? Let's say a scooter sticks on in a restriction. Total instantaneous silt-out. Hopefully you have enough time to find the line. You sure won't have time for much else before you're blind. What happens to the donor switch, SPG monitoring, etc then? If you're in flow in a spring, the stuck scooter will blow silt down your route of exit until you get it shut off.

As for being unlikely, the simultaneous light failure mode really simulates silt-out conditions. Not so unlikely. (Agreed actually assuming nine simultaneous light failures is silly.) Silt-outs in cave can be so bad you literally can't read your gauges no matter how many lights are burning. Seems to me your procedure better contemplate donor switch/gas management in a three way without being able to check the SPG or read your watch at all. Hint: They did teach you how to tell time without a timer, right? If you can estimate elapsed time you can estimate consumption and switch point.

 

[rjack321]

I would go so far as to say nobody's died from checking vs. not checking the SPG on an OOA. People die in caves from excessive depth, failure to maintain a continuous guideline, and violating 1/3rds. There are some other reasons for non-cave trained OW divers

There are no scooters in Cave1, but in event of any failure the most important thing you can do is stop. More than anything, this is what the backwards kick is for.

You can then reference the line. Only then should you be addressing the problem.

A mad immediate dash/grab for the line is not what you should be doing. You would the cause of any silt - relax, slow down, deal with any issues calmly. The line should never be outside of arms reach anyway.

All of this is why you have a 60ft breathhold test. You can hold your breath for a moment to calmly address problems. You will also be doing S-drills further and further apart as the week goes on, up to 30-40 ft apart.

At the end of the week you realize that OOA and lights out aren't the big issues anyway. Navigational errors are the ones that are always looming.

 

[Kendall Raine]

I would go so far as to say nobody's died from checking vs. not checking the SPG on an OOA. People die in caves from excessive depth, failure to maintain a continuous guideline, and violating 1/3rds. There are some other reasons for non-cave trained OW divers

There are no scooters in Cave1, but in event of any failure the most important thing you can do is stop. More than anything, this is what the backwards kick is for.

You can then reference the line. Only then should you be addressing the problem.

A mad immediate dash/grab for the line is not what you should be doing. You would the cause of any silt - relax, slow down, deal with any issues calmly. The line should never be outside of arms reach anyway.

All of this is why you have a 60ft breathhold test. You can hold your breath for a moment to calmly address problems. You will also be doing S-drills further and further apart as the week goes on, up to 30-40 ft apart.

At the end of the week you realize that OOA and lights out aren't the big issues anyway. Navigational errors are the ones that are always looming.

I was trying to point out that a procedure which assumes events occur in a prescribed sequence sometimes doesn't work so well. I know scooters aren't part of Cave 1, but the training is all about procedures that stand the test of circumstance. Just trying to get people to think past the nuances of whether to show everybody the gauge or not show everybody the gauge. You know, limber up the mind and imagination a bit. Nothing more.

To that end, sometimes all visibility is the first thing to go. Instantly and without warning. The scenario I was describing is one in which the scooter has stuck on in a restriction (faulty relay), impacted the ceailing or floor and caused an instantenous silt-out. In this situation there is nothing to "reference." Visibility has gone from 200 feet to zero in about one second. You can't see the line, your buddies, your gauges and your light is a dim glow an inch from your face. Your buddies, behind you, are also instantly blind without knowing what happened. You're stopped alright, now that the scooter is jammed nose up on the ceiling while everything behind you for fifty yards is a cloudy mess and growing due to prop wash. You're 9,000 feet back. In flow, you'll be swimming with the silt cloud on the way out. True, it will diffuse over distance, but the point is viz is shot for a long time.

Agreed, the slow relaxed approached is often the right way to deal with a cascade of problems. If you have that luxury. Sometimes you don't and your manual is back in the truck. I'm not just constructing a horror show for fun. The scenario above happend to a friend of mine five years ago in Dos. They didn't have an OOG, but that isn't too hard to imagine if, while trying to arrest a runaway scooter, you smack the ceiling and break a manifold. High speed problem followed by instantaneous lights out followed by OOG.

 

[rjack321]

Agreed, the slow relaxed approached is often the right way to deal with a cascade of problems. If you have that luxury. Sometimes you don't and your manual is back in the truck. I'm not just constructing a horror show for fun. The scenario above happend to a friend of mine five years ago in Dos. They didn't have an OOG, but that isn't too hard to imagine if, while trying to arrest a runaway scooter, you smack the ceiling and break a manifold. High speed problem followed by instantaneous lights out followed by OOG.

Sure, but they don't teach you these things in class because by and large they aren't the cause of fatalities. The root cause in your scooter scenario is failure to stop. Whether you're riding a scooter or not, the reactions are the same - 1) stop, 2) reference line, 3) address problem. I would postulate that sequence will stand the test of time, although with only 16 cave dives I don't have enough experience to claim it has myself.

There was another fatality in Egypt this week, 300+ ft on 17/20 = diving to excessive depth IMO.

 

[DIR-Atlanta]

I think the point that Kendall is trying to make (which is a valid one in my opinion) is that you can't predict in what order failures will occur. If you have a sudden instantaneous loss of visibility (for whatever reason) and then have to do an air share (for whatever reason), then the idea of showing the SPG kind of loses its appeal. You and your buddy can't see it anyway, and checking it just wastes valuable time.

In other words, it doesn't make a whole of sense (to me anyway) to rely on an emergency procedure that assumes reasonable visibility - you might not have it when the time comes.

 

[rjack321]

OK I get it now.

PS I don't show the SPG (despite the fact that I was partially trained by AG). I would show it if I was making "complex" decisions and wanted to assume my buddy that we had adequate gas. "Complex" would be swimming horizontally/diagonally in OW for awhile vs. a direct ascent. Complex would not be exiting a cave (since there's no other option).

 

[Kendall Raine]

Sure, but they don't teach you these things in class because by and large they aren't the cause of fatalities. The root cause in your scooter scenario is failure to stop. Whether you're riding a scooter or not, the reactions are the same - 1) stop, 2) reference line, 3) address problem. I would postulate that sequence will stand the test of time, although with only 16 cave dives I don't have enough experience to claim it has myself.

There was another fatality in Egypt this week, 300+ ft on 17/20 = diving to excessive depth IMO.

If by "failure to stop" you mean failure to stop the prop, that's true. Disengaging the clutch is the first task in a runaway. Rereading my post you'll see in the scenario the scooter stopped forward motion the moment it hit the ceiling and the diver failed to arrest the prop before the silt-out occured. The diver was expecting the scooter to stop when he let off and it just stayed on, catching him by surprise and impacting the cave in less than a second. Stuck relays are more common than lightening strikes.

DIR-Atlanta has it right, as usual. The point is a broader one. You should be able to do everything to accomplish an exit, even estimating remaining gas supply, without the benefit of visibility.

As for causes of fatalities, your remark "Sure, but they don't teach you these things in class because by and large they aren't the cause of fatalities" whatever "these things" are, is a pretty authoritative statement... I wonder where it comes from.

 

[rjack321]

top 3 causes of death in trained cave divers
excessive depth - from narcosis and/or exceeding MOD
failure to maintain guideline
failure to reserve 2/3rds gas for exit

In that order from accident analysis. There's a slightly different list for OW divers. None of which has much to do with scooters, spgs, or air shares.

Scooters blowing out the vis is not a high risk event. If it happened it woud be high risk, it just doesn't happen very much. Scootering in a cave is at a vastly different level than "do I check my spg after an s-drill or not" kinda question/issue.

If I dove in kelp forests all the time the concept of the SPG check would have more merit IMO.