DumpsterDiver emergency ascent from 180'

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Over 25 years ago there was a board titled "Free dive list." seventeen years ago (2000) they organized and sponsored the huge 2000 Free dive Party which was the last gathering of the worlds "Fathers of Free diving and Spear fishing." It was a very monumental event in the history of spear fishing. The 50 or so fathers came from all points of the globe for this last hurrah; Central and South America, Europe, Australia, the Pacific Islands and North America -three were honored from Orange County California the late Ron Merker, Allan (Omar) Wood and my self

In honor of the event and the Fathers posted the following on the Free Dive List:

"We Fathers of Free Diving and Spearfishing have been honored as pioneer participants in a noble sport where one matches their skill in a very hostile enviroment with that of his finney adversary in an activity that has become internationally known as "Spearfishing."

Spearfish with great dignity and pride in this the noblest of all man's activities,but with restraint and selecive spearfishing rather than wholesale slaughter, for with every activity there is a Beginning; a Middle; and an End............"
We the "Fathers" of this great activity were honored to have been a participant in the Beginning, we are some where in the Middle and if precautions aren't established and restraints aren't practiced the End of spearfishing can be in the immediate future"

~~~~~~~~~~~~~~~
Always remember this:

"if precautions aren't established and restraints aren't practiced the End of spearfishing can be in the immediate future"
~~~~~~~~~~~~~~~~~~~~~~~~~~
FYI
Only a hand full of the Fathers have survived the passage of the last seventeen years ~~ One by one they have passed on and are now diving on that big reef in the sky. and
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@Steve C.....

The individual in question certainly was not a "Father" and certainly not a particularly good spear fisherman judging from his videos and his attitude of wholesale slaughter of small reef fish and shooting barracuda for target practice.

I cannot judge and do not know how he is judged as a free diver but suspect his skills are some what lacking when compared to a skilled free diver/ spear fisherman.

He is certainly not a good role model for this or any spearfishing - free diving - SCUBA diving board

Sam Miller 111.

.

SDM
 
Based on his prior videos he has done a lot of free dive spearfishing. I cannot evaluate how skilled he is.

By my own personal values, free diving violates ALL of what I consider reasonable standards. Stepping off the boat without a tank or reg much less that tank turned on is a BIG first one for me. :)
 
Remembering his thought process from previous threads:

@dumpsterDiver tank mounts a smallish pony (al13) because he primarily spear fishes and needs the manuverability and open chest area that a larger slung tank would decrease.
 
I think context is important in this discussion.

1. In many of the previous threads regarding pony bottle size, the question most often arises when a diver says they are planning to purchase a pony bottle, and solicits suggestions on size. In that context, one consideration that not infrequently prompts a recommendation for a larger bottle is ‘buy once’. If a recreational diver is going to own one and only one pony bottle, what size provides the broadest possible coverage for diving within limits – i.e. to as deep as 130’? Otherwise, it would be appropriate, albeit probably not cost-efficient, to have an assortment of pony bottles.

2. The recommendation for the size of the bottle is then based on what is represents a reasonable gas supply to allow for a normal, controlled ascent from the maximum likely depth (130’). And, the recommendation is based on logic, and mathematics, not hope (i.e., I hope this bottle will get me to the surface) or supposition (i.e., I think I can make it to the surface with this bottle).

3. The calculations usually allow for a) 1 minute at depth before the ascent begins (while the diver attempts to sort out whatever problem s/he encounters, b) a normal, controlled ascent to 15 feet at an ascent rate of 30 fpm, c) a 3 min safety stop at 15’, and d) a normal, controlled ascent to the surface, again calculated at an ascent rate of 30 fpm. The other factor that is usually considered is a probable increase in RMV, reflecting some degree of stress associated with encountering an unexpected, emergent situation. In my case, I have a RMV of 0.7 cfm – it has been that way for at least 10 years, and doesn’t change. Others may have a lower rate, some may have a higher rate. But, I know what mine is. And, when calculating gas requirements for an emergent ascent from 130’, I use a RMV of 1.0 cfm. So, for ME, I need 21.1 cf to get to the surface from 130’, using a normal, controlled ascent under some stress. (Even if my RMV didn’t change, I would need 14.8 cf). Therefore, neither a 13, nor a 19 for that matter, is going to do it under realistic projections, so I choose a minimum bottle size of 30 cf. Sure, I could ascend faster. Sure, I could blow off the safety stop. Sure, I could ‘skip breathe’. But, why take the risk of turning a successful extrication from an emergent situation into a different, equally serious emergency?

If my maximum depth is 100’, I could just make it to the surface with 13 cf at my normal RMV, but would need 18.6 cf at a RMV of 1.0. From a depth of 60’, I would need 10.7 and 13.3 cf. So, for ME, there isn’t a scenario where a 13 cf bottle represents a reasonably prudent redundant gas supply if I follow reasonable assumptions of time, ascent rate, and effects of stress on gas consumption.

4. There are 2 other factors about the video that merit comment, because they, too, represent important insights:
a. The video illustrates one of the 4 approaches to an out of air situation – a buoyant emergency ascent (‘inflating my BC and Trying to get shallower ASAP’). It is fourth in the list of recommended alternatives to address an OOA situation, and follows a CESA. That is not a criticism of DD, by any means, just a description of what is actually seen in the video. And, notably, he was not out of air, he experienced a rapid depletion of his primary air supply. In contrast to a buoyant emergency ascent, one of the safer, and therefore preferred, approaches is an alternate air source ascent which is, in the case of the self-reliant / solo diver, is to switch to a redundant air supply of sufficient volume, and make a normal ascent to the surface – a controlled ascent, with a safety stop.
b. DD did not immediately begin an ascent – there a bit of time consumed while he (presumably) tried to figure out what was going on, after which he started his buoyant ascent (I would have done exactly the same thing, so this is not in any way an implied criticism). Frankly, DD did much better than most divers would. Human beings don’t immediately react to the unexpected in a time-efficient manner – this was, by the way, one of the important issues addressed in the movie, Sully, when the behavior of the crew was called into question with regard to turning back to LaGuardia vs ditching in the Hudson. It took time for them to realize that they really had experienced the incredibly unlikely – flame out of both engines. A diver is going to take some time to figure out that they have really experienced the very unlikely – failure of their gas system. So, whatever redundant air supply a diver carries should reflect that reality. And, the prudent recommendation is therefore expanded to include allowing for time at depth to address whatever the problem might be.

5. I have never been in a situation where slinging a 40 cf bottle (or a 30) in any way negatively affected my diving, and caused me to leave the bottle on the boat. But, it is conceivable that a 5’1” diver might find the ~25” bottle to be long, and therefore cumbersome. In the water, I do not even notice either bottle - no notable effect on buoyancy or trim.

Everyone is entitled to dive the way they want. If someone chooses to dive deep without a pony bottle, that is their prerogative. If they dive to 130’ and choose a 6 cf, or a 13 cf bottle, that is their prerogative. For me, based on math and logic, a 19 cf bottle is the minimum size I would carry – if I am going to carry a pony bottle. And, a 19 is not an optimal redundant air supply, again based on math and logic, for a dive to 130’, so for me, a 30 is the minimum I would carry to that depth, even though it provides more gas than I calculate I would actually need. So, if a diver on SB asks, what size pony bottle should I buy, my answer is most likely to be a 30 cf, IF they are only going to buy one bottle, and IF they are going to be diving to recreational depths.
Cuzza:
It's definitely personal preference and dive plan dependent, though I think one should also consider if it's too big, a pain in the ass, etc., then those items tend to stay home or are left on the boat.
2airishuman:
The balance point is when the reserve gas supply system becomes large enough to pose additional practical difficulties of one kind or another that lead to decisions being made to dive without it. I believe that the best practice is to encourage the use of reasonably sized pony cylinders that allow a safe, immediate ascent to the surface based on actual gas planning using the intended depth and SAC rate (and a reasonable multiplier for stress).
I very much agree with both sentiments. Personally, I don’t find a 30, or a 40 for that matter, to be at all cumbersome. In fact, my first (and for many years, only) bottle was a 40. But, that is ME, others may differ. I also do / will not use a remora attachment to my backgas cylinder, and slinging anything less than a 19 is a PITA, for ME. I occasionally recommend a 19 to some divers. I don’t own one m yself, simply because there is not utility for me, when I already have 30s and 40s. And, I already have more than enough cylinders in my garage.
 
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Excellent Job of explaining it Stuatv thanks.
The posts I quote bold and colour added by me point to a diver who has pushed the edges with aggressive diving and what many would consider pushing the edge of safety. He has done it so long that he has gained confidence to conduct dives like this. That is the very essence of the Normalization of Deviance. Call it what you choose but in the end complacency is a factor in the death of many highly experienced and competent divers.

No, he just frequently posts about his extremely aggressive dive practices, he's been doing it for years. If that's not 'advocating' I don't know what is.

If an unknown diver posted half the crap that he has, he would get skewered on this board. It's not much different than a kid posting a video of his speedometer at 120 on facebook.

It should be noted that despite his nonchalance with respect to what many people would consider safe diving practices and the relatively large number of incidents he has had over the years that he's very cool under pressure. One of the reasons he probably managed to make an ascent on an AL-13 from that is that something like this probably won't even have stressed him out.

In other words, I wouldn't necessarily take this as proof that any diver would have made it safely back to the surface with a 3l pony bottle from that depth.

R..

Glad he's fine. Certainly a clear head and an iron will helps in such situations and he handled it well.

I too would not advocate putting one's self in the situation with inadequate bailout. The same logic applies to a CESA from 180'. Some of us have done it and it can be done without injury (sometimes). Just because it can be, doesn't mean it should be relied on.

Regards,
Cameron

I think it should be noted this was a bounce dive with no planned deco.

ok, so here's what happens here and why it is still stupid.

After watching the video that is a 4 minute ascent from 180ft, with no safety stop. Avg ascent rate of 45ft/min. Quite slow given the circumstances, though I think failure to perform a safety stop on a 180ft dive regardless of whether it is a bounce dive or not is just dumb.

13cf is more than enough to take you up from that depth, with that ascent rate, with no safety or deco stop, and no time at the bottom to resolve an issue. What it can't do is keep you with your buddy, bring you back to the anchor line, resolve a situation at depth before starting ascent, complete a deco stop, or deal with an escalated SAC rate.
With his ascent rate, that bottle contains enough gas to allow up to a 0.8cfm SAC rate with no time spent anywhere. Just a continuous ascent rate. If you want to plan that cavalier on your safety buffers then so be it, I've done stupider things in the water as has anyone who has been diving for any length of time, but anyone who advocates that that is safe and smart has never done the math.
 
I'm pleased that there are so many insightful replies.

I would tend to agree, but the ease of slinging an AL40, its buoyancy characteristics, and the amount of gas....I think an AL40 makes tons of sense. Having seen people struggle to cleanly mount and carry everything from an AL9 to an AL19 makes me want to stay away from those.

I'm OK with that point of view although I do not share it. My 40cf cylinders are HP steel and I have never dived with an AL40, so perhaps they are easier to carry for whatever reason. I have an HP11 and an AL19 that I use for some solo dives, and twinsets I use for others. I don't find that the HP11 or AL19 are particularly difficult to carry or mount, but it is necessary to leave enough slack in the top bolt snap that it can be handled readily. One of these days I'm going to experiment with using bungee material for the top bolt snap attachment to try to get easy handling combined with better trim.

@2airishuman
on some of the arguments for redundancy and how much is practical to carry you are correct. That is why we don't dive to quarters in most caves and don't reserve stupid amounts of backgas when diving in open water.

The difference of slinging an al13 vs an al40 is pretty simple. no matter how you spin it, an al40 is actually easier to carry. It's less negative when full, only an inch larger in diameter which means reg and valve clearance is usually less of an issue, and because of the extra length, it's easier to sling and handle in the water.

Again, I find an AL19 to be the sweet spot for most dives where I carry a pony.

You need an AL40 to make a safe ascent from 130ft factoring a 1.0cfm SAC rate which is safe average considering it may well be higher during the minute allotted to situation resolution but lower during the shallower portion of the ascent

I've done the math and I agree with your assessment, and would use a larger pony, or a twinset, at that depth, which I believe I made clear upthread.

What math do they use that you don't agree with that says that a smaller tank is better/safer to take than an al40?

I use a 30 fpm ascent, a 3 minute safety stop, 30 seconds at depth, a 1.0 SAC, and a 90% useful fill. By the math that's good to a little more than 110 feet. I don't push it that far, and prefer to use a twinset for solo dives beyond 80 feet or so.

depth=110
ascent = depth/30 * sac * (33+depth/2)/33
deep = 0.5 * sac * (33+depth)/33
safety = 3 * sac * (33+15)/33
(ascent + deep + safety) / .9
18.120089783

so what happens if the gas loss had happened at 10 or 12 minute mark when he had clocked 8 or more minutes of deco

I don't believe he intended to stay at depth that long.

Of course it depends where you dive. I had an incident 2 years back that changed my thinking. I was divign a 15L (HP100?) and a AL 30, my wife a 12L and AL 30. We left the ridge (30m) on a pinnical of a site we've dived many times before well within Rock bottom and well within NDL because we would slowly come shallow to comlete a 60 min dive.

This time however we got smashed by a down current and we stopped at 55m. We litterallly had to crawl up the rock out of the current, screaming through our gas and incuring deco.

Long story short, I had between both cylinders maybe 25 - 30 bar As it happend another team on scooters saw our prdicament and met us with 80% to ensure we could really off gas.

By your statements you consider AL 40 to be too large - which is fine, everyone is entitle to their opinion.
Now however, on sites with no hard bottom at recreational depth I now sling an AL 80

Again, I posted upthread that it does depend on the dive. I myself sling at AL19 or dive a twinset on solo dives, depending on my familiarity with the dive site, my assessment of risks, the depth, and so on. Now that I have an LP72 twinset I find that I prefer to use it in situations where I have used an AL19 pony on the past, but I do have the pony at hand for situations where I'm doing more solo diving than I have twinsets.

I figure that after an incident no-one has everr wished they were carrying less gas

I can assure you that there have been many shore exits where I wished I was carrying less gas.
 
All good points @stuartv, but how does experience as a freediver, (I have no idea how experienced/accomplished a freediver he is) factor into the situation?

If you are easily capable of sub 100ft freedives does that change things?

In my very limited experience I would imagine there would be a huge difference in an accomplished freediver doing this dive vs someone with no real free diving experience.

It does not change anything regarding MY evaluation of normalization of deviance. I don't have any training for scuba diving that allows for doing anything differently based on free diving skills. I suspect that there is no such scuba training. So, his dive would still be a deviation from standards. Which he has normalized.

Remembering his thought process from previous threads:

@dumpsterDiver tank mounts a smallish pony (al13) because he primarily spear fishes and needs the manuverability and open chest area that a larger slung tank would decrease.

For diving deep, I would use back mounted doubles as a starting point. For diving solo, I would use back mounted doubles as a starting point. Back mounted doubles would not reduce chest area. A compromise on maneuverability based on going deep and solo only seems reasonable.

An AL40 could be mounted on the side of a back mount single tank, just like the pony he was actually using. For solo diving, I would absolutely be willing to use an AL40 and a single tank instead of back mounted doubles. But, if I follow my training, a deep dive with an AL19 would not be acceptable.

Also, I just want to be clear, I am not slamming DD or criticizing him. I am simply trying to post an objective evaluation of this dive based on the question that was asked "how was this normalization of deviance?" I don't believe there are very many absolutes in life. "Normalization of deviance is always bad" is not an absolute I would agree with. It is usually bad. Almost always? Maybe. ALWAYS bad? I do not think so. Sometimes, normalization of deviance is really the new Best Practice (though certainly this case is not an example of a Best Practice).

Saying that DD's dive was an example of normalization of deviance is NOT me making a judgment about whether it was good, bad, or indifferent. I am glad he got out unharmed and I definitely admire all the skill and poise that was demonstrated.
 
That is the very essence of the Normalization of Deviance

For context, and to be clear, I don't emulate DD's overall approach to diving, and don't hold it up (overall) as a model that others should follow. I posted the video because it is a rare example of someone performing an ascent on a pony bottle, from depth, during an actual emergency. While I myself use a larger pony cylinder that is slung, I do believe that DD has a valid, carefully thought out approach to the use of a pony cylinder, both in terms of size and configuration. DD has an Air2 on his primary cylinder and a back-mounted pony connected to a necklaced regulator.

I do not believe that DD's approach to diving results from normalization of deviance. I believe he has a carefully considered, highly reasoned disregard for recreational diving limits that is rooted in the diving approach used for commercial spearfishing. From what little I know of commercial spearfishers who use scuba, I do not believe his approach is unusual, novel, or edgy in that context. I believe he has held a commercial fishing license for some years.
 
@Steve C
You were not involved in diving before the bubble machine arrived in the very late 1940s.

There was only one major diving universal activity and that was spearfishing which was practiced by young athletic water wise young watermen on the west coast of the US.

Equipment was crude or home made, There were no instructional organizations no instructional books, no magazines, just plain ole American injunity...now we have instructional organizations, instructional books, magazines and dive masters with limited experience in free diving.

Try it some time ... then possibly you will understand the trials and tribulations experienced by those who began diving in the 1920s, 1930s and 1940s...We were free divers spear fisherman not one who stuck a gun on the nose of a fish and pulled the trigger-- there is considerable difference

<< Like you hat ...A Canadian "Tilley Hat? " I have worn a Tilley for 40 years- they are guaranteed for life- one becomes worn send it back and here comes a new one..I have had 4 so far -- working on the 5th one >>>

The California sun is shinning ...off to the beach with my little black dog Lucky

Cheers from where it all began in Kalifornia

Sam Miller, 111
 
It does not change anything regarding MY evaluation of normalization of deviance. I don't have any training for scuba diving that allows for doing anything differently based on free diving skills. I suspect that there is no such scuba training. So, his dive would still be a deviation from standards. Which he has normalized.

Sure, my point is what are the standards for free diving and is this a deviation? If you are trained in both than the standards for both would apply to your decision making/planning process I would imagine?
 
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