Buddy OOA in Challenging Conditions

[FritzCat66]

Thanks, Fritz. What would be the advantage to handing over your primary to your OOA buddy and breathing off your pony?

Well, in your case you still had plenty of gas for the panicky diver in your primary (1000psi is roughly a third of your backgas - even with a typical aluminum 80 you're talking 20+cf or so), while even a full 13cf pony is just barely enough for an ascent from that depth breathing normally. You were right to be concerned that she would use up the pony! You might have just used your octo at first (i.e. both breathing off your primary cylinder).

I am presuming that, generally in these kinds of situations where you are the donor, the other OOA diver is probably more panicky and likely to be breathing harder and using up gas quicker, so if I had as much in my primary cylinder as you had, I would let them breathe that primary tank with the higher capacity, then switched to my pony for myself if I had to once the main cylinder started getting low.

In my case, like I said I backmount my pony, so giving the other diver the whole pony isn't really an option. Sure, in your situation I could give the other diver the pony reg, but the longer 5' hose on my primary reg would give them more room to maneuver than the three-footer on my pony.

What are the hose lengths on your primary reg, your octo, and your pony reg?

Also, just out of curiousity: you say you had 500psi in your main cylinder once you were back on the boat, but how much was left in your pony, do you know?

 

[Puffer Fish]

Interesting issue.

I am always amazed by attempts to manage decision making at the moment of any event. As well as the micro management of specific gear choices.

But consider, for just a moment:

1. Crisis events are a series of linear choices...choices that have to be made in seconds, with no ability to ask questions, consider options or take the time to think.

2. Whatever the actual situation was, no one could write down all the micro detail that lead to each specific choice. One is faced with a complex environment, and you get to pick a course of action.

3. Once you pick one, that will lead to the next situation, where another decision has to be made... and the process starts all over again.

I once had a really terrible string of actual rescue events, all packed into a short time. Just being at the wrong time when someone decided to to make mistakes. It was not the first one, or the second ... nor the third or even the fifth that got me to go back over and honestly look at events. My final take was that, I don't care who you are or how much you think things thru or how practiced you are, if you get in enough situations, you will make choices that will accidentally lead to a dead end. I was successful in every event, but some of that was blind luck. You pick choice "C" and that lead to another set of choices, and you pick "A" and on you go...no one can get them all correct, all the time.

But you can completely avoid the situation. A pony is an emergency air supply... EMERGENCY. Want to have a long safe diving career? Avoid having one.... and if you do, make it a simple one.

What went wrong with the dive was simple buddy dive management. I dive a lot with insta-buddies, I do about 65% of my dives to at least 90 ft, and I dive a lot. I have never had a buddy run out of air... and I don't plan on starting that this weekend.

Note: Was certified in 1966, so that has been a lot of dives

When two divers jump in the water, only one will be limiting the dive. Which one that is, is the first thing each diver should determine. Once that is known, then both divers are concerned about the same tank of gas.

Most of the time I am the one left with a lot of air, but I know women that have a SAC rate that makes mine look bad...so most of the time I casually check mine and worry about the other diver, and ever so often I worry about mine. (worry is not the correct word... manage the dive with would be better, but it takes more typing)

I check both gauges at the surface, at the bottom and next at about what I believe will be roughly the 1/3 of the bottom time....and adjust my expectations as needed. If our air consumption were to change during a dive (we reverse air usage)...ok, just change the focus.

Either diver running out of air is the one thing that should never, ever happen.

Regarding the line and holding on.. like dumping weights, there is a time to hold on and a time to let go...breathing should alway trump holding on. It is far better to be breathing and adrift, than to drown...

Pony bottles are nice (even a 13 cfm one), if they are going to be used in a real emergency (as in... something breaks), not when people just forget to go back to the boat before running out of air. For that you really need something big.. but big means drag in current, and possible handling issues, and there you go, back to the sudden series of choices one is trying to avoid having to make.

Glad everything worked out.

 

[FritzCat66]

A pony is an emergency air supply... EMERGENCY.

Pony bottles are nice (even a 13 cfm one), if they are going to be used in a real emergency (as in... something breaks), not when people just forget to go back to the boat before running out of air.

To me, Beiji's kind of situation is an emergency worthy of using the pony, although as I mentioned in my post I might not have jumped to it at first. But not treating it like a worthwhile emergency and holding it out would be, IMO, to be guilty of the same kind of error that the captain made in this situation; to wit, being stingy with a critical resource (the O2, in his case) when a diver is asking for it. What kind of "real" emergency was he waiting for?

Everything else being equal, by carrying the pony she had 13cf more gas in reserve than if she wasn't carrying it, and she almost needed some of it (not quite, since she says she had 500psi left in the main cylinder - which is about 13cf on the nose if it was a 77.4cf AL80).

 

[fdog]

Thanks, Fast97rs. What kind of signal does one use to mean "Please repeat your signal"?

<snip>

Depending on the person I'm diving with, it varies. Famliarity breeds brevity of signaling, if you know what I mean.

"What? Say that again?":

• Very familiar team mates: Head cocked in the "RCA Victor" pose.
• Occasional: Pointer finger crooked in the shape of a question mark.
• Hardly ever dove with you: pointer finger sideways, making a circular motion, like a wheel rolling toward the other person

All the best, James

 

[Puffer Fish]

Fritz, it is, but only because someone ran out of gas. I don't think anyone carries a pony, thinking... well if someone forgets to keep track of their gas, I'm going to need this.

By "emergency" I meant something out of your control that breaks, and you are heading to the surface.

In an emergency, one does not do a safety stop.

To me, Beiji's kind of situation is an emergency worthy of using the pony, although as I mentioned in my post I might not have jumped to it at first. But not treating it like a worthwhile emergency and holding it out would be, IMO, to be guilty of the same kind of error that the captain made in this situation; to wit, being stingy with a critical resource (the O2, in his case) when a diver is asking for it. What kind of "real" emergency was he waiting for?

Everything else being equal, by carrying the pony she had 13cf more gas in reserve than if she wasn't carrying it, and she almost needed some of it (not quite, since she says she had 500psi left in the main cylinder - which is about 13cf on the nose if it was a 77.4cf AL80).

 

[FritzCat66]

Fritz, it is, but only because someone ran out of gas. I don't think anyone carries a pony, thinking... well if someone forgets to keep track of their gas, I'm going to need this.

It's true that the intended use of my pony is for me, and it sounds like that was Beiji's intent in carrying her 13cf as well. But in a pinch, more gas is more gas.

By "emergency" I meant something out of your control that breaks, and you are heading to the surface.

In an emergency, one does not do a safety stop.

This I disagree with - the way I was taught to size a pony (by SDI) is to consider a few minutes at your typical maximum depth to resolve your issue, then a normal ascent with normal stops - even deep stops if that's your thing; use your RMV/SAC, maybe with a modest multiplier for breathing a bit harder, and base your pony volume on that. So, normal stops should be part of pony utilization.

 

[Beiji]

What went wrong with the dive was simple buddy dive management

Agreed. and thanks for your other tips and comments.

 

[Beiji]

What are the hose lengths on your primary reg, your octo, and your pony reg?

Also, just out of curiousity: you say you had 500psi in your main cylinder once you were back on the boat, but how much was left in your pony, do you know?

I have short 3 ft. hoses on both my primary and pony regs, and I have an Air 2, not an octo. I will be thinking hard about whether to make changes in light of this event.

Unfortunately I didn't think about checking the pony pressure until the next day, and it had already been filled.

 

[Ayisha]

...even a full 13cf pony is just barely enough for an ascent from that depth breathing normally.

Well, it depends on the diver, and that is not true of many females. For example, I carry a 19cf pony, which is almost 1/3 the size of my normal tank, an AL63. I do the majority of my diving in extremely cold, deep, low viz environments and I usually come back with about 1300 - 1500 psi in my AL 63, going fairly close to the NDL's. I have never used my pony, but I'm quite certain that since it's close to a third of my normal tank, and I use around half for my entire dives, the pony is more than sufficient - and not only enough for an ascent. I'm quite sure that a 13 cf would be enough gas for many women and a 19 cf would certainly be enough for most, if not all, women doing recreational NDL dives. The weight on land is a concern for many females, especially petite ones.

Now if someone is considering tech diving in the next few years, then sure, anything less than a 30 or 40 cf would not be very useable for that purpose.

 

[Beiji]

While  a 2-3 foot swell is not bad it can be a bit challenging.   I'm not clear on the max depth of 91 feet being 4-6 feet below the bottom of the descent line.  Unless this was a weighted shot line that was NOT attached to the wreck.

Thanks for your comments, Joel. In the above, I just meant that we left the line and dropped down a few feet. The wreck is actually at 110 ft.

It sounds like no one made a PLANNING DECISION prior to leaving the boat. The assessment of the current should have been made by crew prior to divers getting in the water.  

90% of all dive accidents happen on the surface.  From the description of the conditions this should have been set up as a "negative descent dive"  where the divers enter the water with the clear expectation of taking the guideline in hand and dropping down to the dive site.  This allows for an easy entry in a challenging environment and does NOT risk getting beat up on the surface by the boat OR waiting around for others to get in the water.    This is a technique that should be practiced by any divers who plan to dive in currents from a vessel. 

It would have helped. Trish said she used a lot of air on the surface.

This comes back to Pre-Dive Briefing.  Wreck diving requires a diver be adept at a variety of propulsion techniques including the pull-and-glide.  The hydraulic action of the ocean will push and pull you on a wreck sometimes in a negative manner. One needs to evaluate the conditions on the bottom and get into the "lee" of the wreck or as was mentioned work inside.  However once you are inside you are in an overhead environment that brings with it a variety of hazards if one is not trained in advance. 

This particular wreck was made safe for divers before it was sunk, with access to the outside always available. That's why we hardly saw any other divers on the top deck.

Diving with a new partner that you know little about is like going on a blind date with someone you found on Craigs List.  It's a serious crapshoot.  Pre-dive discussions about what's important to YOU and to them should take place.   

This sounds like it was not a multi level dive but a square profile.  As such gas planning needs to be handled much more carefully.  Thirds, "rock bottom" etc all need to be employed. 

Agreed.

With the short dive time you had (assumed) blowing off the 3minute safety stop would not have been a bad idea.  a 90 fsw dive on EAN 32 provides you with   50 minutes of no-stop dive time (USN EAD conversion basis).  I'm going to suspect you did not get more than 20 min of on-the-bottom time.    A safety stop is of no use if you have nothing to breathe.  (I assume your pony had AIR in it. Dont worry about using it on an EAN dive that is no-stop) 

I think my total time including ascent and safety stop was 27 minutes.

If she was on the surface and breathing she was not out of air.  She may have needed assistance but she was not out of air. 

Well, it certainly got attention and brought help quickly. 

This is a crew issue.  If they already had one diver who was exhibiting panic and had to get her on the boat. There is no reason you needed to swim. Wrap the line around your arm and have them pull you in.   Good deck people do that.  But, smart on your end to have thought of the process of -- "stop fighting the current, drift and let them pick me up." 

Good to know it's not out of line to need that kind of help.

Sorry, Mike is not a medical expert. If a diver asks for oxygen for WHATEVER REASON, he is to provide it to them. PERIOD.  A professional dive vessel should carry on board sufficient oxygen for at least 2 divers for at least 2 hours PLUS the time of transport to medical services. 

It's quite possible she had a large build up of CO2 from the struggle back to the boat. That would be evident in a head-ache.  She also could have been suffering from a gas embolism (though not likely as those symptoms would have presented sooner) 

Divers need to be vigilant when asking for oxygen. 

 

Also good to know.

As it is said you cheated death one more time.   Now that you have a clear understanding of some of what happens when things go wrong you can make better plans next time to ensure that they dont.    If you dive with a short hose, get a 5 or 7 footer and learn how to use it.  If you plan to go out to places where you are with divers who you are NOT familiar with consider a quality Rescue Diver Course AND Divemaster. Not that you want to be a DM but you will learn a LOT of quality self rescue, and self preservation techniques.  Don't get trapped in the "slave to DM or DiveCon mode."   Find a top end trainer who can get you through the material and training skills. 

Why would a longer hose have helped in this situation?

I've actually been thinking of doing the dive con course just for the training.