sled diving within AIDA

[fcallagy]

Bill can you expand on what you think is a safe set up. I would have thought that after using it succesfully most would have moved to herberts cone of foam for resurfacing as it makes all else redundant. this has been mentioned already. I would have thought that nlt was getting safer despite the increases in depths with using more technology sonar etc.
I really enjoyed my limited time on the sled down to only 40m. i think it has its place in our sport. We still dont seem to find out what happens in these accidents, ie diver error due to narcosis or entanglement or deep BO? I would be in favour of a pausing NLT at least until things are analysed further but think we may be having a similar debate on cw in the future, what causes deep BO? Do we know? How do we find out?

 

[Will]

What we need is people follow the safety guidelines.

The problem is that they ARE being followed, but have proved repeatedly insufficient despite numerous revisions.

Just because we have deep bo's in constant(yes, we have a numbers of those), we don't want to remove the discipline.

In tens of thousands of training/competition dives in CWT/CNF/FIM there has never been a blackout deeper than 35m that we know of. In the last three VWT record attempts there have been two blackouts at 40m.
These, and other, glaring statistics are why there has been a proposal to cease VWT/NLT regulation but not CWT. But they are not the only reason. The contrasting athleticism required, and the consequent reflection on the image of the sport are other very valid reasons.

Regarding the remaining criticisms of the statistics in the proposal document, please refer to post #150 ("relative risk). We have analyzed the only data that is available on mortality and completed dives. Even though "number of mortalities per AIDA registered dive" isn't a precise measure of risk, it does give an impartial representation, and when that risk value differs by several orders of magnitude (between NLT and the other disciplines) then any minor error margin in the means of calculation becomes irrelevant.

 

[pehtran]

The contrasting athleticism required, and the consequent reflection on the image of the sport are other very valid reasons.

Looks like the debate has reached the point where the same arguments are just played and replayed over and over again. Especially these two in the quotation are very subjective and as such are "very valid" just for those who agree with them. The third argument regarding safety is very worth considering but some are convinced that we just can not run away from the fact that it is dangerous and leave it to whoever may want to govern it.

 

[Billextreme]

Will,

You say that the safety guidelines are followed but this is not the case with any of the 4 fatal-accidents, Cyril, Audrey, Loic and Adel. Then you have to remember that the AIDA guideline was done after Loic died, and that Adel open his lanyard himself. (this for reason we only can speculate in). Then you talking about deep water bo's in CWT, everything deeper than 25 is fu## deep in Constant and we have not soo few of those. AND, again.. you try to some statistics from an unknown number of NL training dives. Training dives done outside of AIDA (that is the one you crusade against) and then compare it with organized competition dives, done inside of AIDA. This kind of number-magic is out of the air and completely irrelevant, to put it nicely. If you could present correct total number of NL trainings dive, then I could start to listen to you. Or even better, why not using official AIDA WR attempts in NL and VWT.

:::


And then we have the question from Mr. Feargus,

You ask me to expand on what I think is a safe set up.

Safe set up start with the athlete himself, as always.

And the order of ”safe set up” is normally like this:

1. The Athlete.
2. Safety Freedivers, including the lanyard.
3. Counter Ballast System, including the lanyard.
4. Safety Scuba divers, including the lanyard.

Number one on the safety set-up-list is the core of the whole dive and also the main safety. This mean that you have a very well prepared athlete, extremely well trained, done a lot of deep training to depths similar to the one that will be done. This with great excellency and without any performance problem. Then when we are talking about sled-diving, the athlete need to know every single thing about the sled, how it works (and how it not work). The athlete needs also to know everything about how the lanyard work and how dive with it. (i.e. have done a lot of practice with the very same lanyard) Then to just give you a short list of other things under ”well prepared”, we should mention, eating and drinking, well rested, perfect worm-up before the dive. And of course also mentally prepared to the whole circus around the dive, and the dive it self.

One example of an athlete not very well prepared is a blackout at deep water, let say down at 15 meter or deeper. Some times we see bo’s so deep as 35m+. If there is no time stealing incident during the dive, let say a fight with a shark, smacking in-to a submarine or a very nasty fishing net, a deep bo is a sign of something big is missing. Here we normally we talking about a lot of deep training to depths similar to the attempted depth, without problems.

Number two is at least two safety freedivers, both good for a 35-40m rescue dive on one breath (with a happy ending that is). Here we talking about freedivers with long experience of being a safety freediver, and have seen and acted-in on numbers of “problems” with freedivers taking to much water over their head. Safety freedivers who know how to act and with what technical skills they need to handle and master to 100%. Safety should know when to dive down (or having a helper who do the count down for them) one safety diving down at the time, and then they alternate. Normally depth for CWT safety is around 15-20m. When we have 85-90m+ divers, the safety use to go down a little bit deeper, maybe down to 25. For deep sled diving the timing is extremely important, and I know safety that go down to 35 to just turn and be with the athlete directly at the turn.

To know here is that if you cover point one and two on the safety set-up-list perfectly, the use of point three is very rare. And those times it have been used is normally because the athlete have announced a much shorter total dive time than the time the dive really takes.

Number three on our list is the Counter Ballast System, including the lanyard. All parts have to work and bring a dive-line including an unconscious athlete to the surface without problem and with a speed that hopefully is greater then 2m per second. There are many different solutions on how to make a really good Counter Ballast System, but the main thing is that it works and that if something stops you have people enough to pull it up, and this with very good speed. Here we have some organizers that use engines to pull the line up, but even here you need to have a back-up of people to pull if something happen. If you use the regular system with a big weight in the other end of the rope, you have to make sure that the distance between the both ropes in the water is great enough so there is no risk they will come close to each other. Here you can use a lot of extra weight, weights that are hydrodynamically made so they go straight down without wobbling or changing of direction. When we talk about CB system we also need to make sure to use the best possible line, a line that will not brake or do any “funny stuff”. A real good and thick climbing line use to work without error (expensive, yes, but worth every cent).

Then the lanyard have to be done perfect and be attached to the diver in the best possible way. You find descriptions on good lanyards all over the Internet and in the AIDA rules you find some specifications on this. I have only some personal comments when it comes to some specific details here and that is that the athlete, when it comes to sled-diving, should not be able to disconnect himself from the dive line. I know that this could be done in a perfect way, and I hope we find this in the AIDA rules in the near future. This together with a special harness over the upper-body with a connecting-point on the back of the athlete just below the neck, between the shoulders will make the best possible body position. There is always plus and minus with each idea, but I think there is a lot more and stronger plus than minuses with this connection-point.

Number four on the list is when something is hindering the line to be pulled up. But if the organizer make sure that they have at least 50+ meters of blue water under the end of the dive line and that the distance between the two lines going down is great enough to eliminate tangling of any kind. The scuba never have to do any safety, this because the CB system + the lanyard is doing the job perfectly and bring the diver to the surface.

When it comes to the sled-design we have to be open-minded and examine all new constructions carefully. We know that the perfect sled is still there to be made and that the design contra materials, hydrodynamic contra speed and weight contra buoyancy are just some of the equations to be solved.

best regards
Bill

 

[trux]

The problem is that they ARE being followed, but have proved repeatedly insufficient despite numerous revisions.

I do not think it was the case at Adel's dive. It looks like he detached his lanyard voluntarily at the bottom plate (there are testimonies he used to do it). That does not sound like respecting the guidelines. Didn't he do it, he could be very probably still with us.

At the older NLT accidents, we also cannot speak about respecting the guidelines (first of all they did not exist yet, and then especially in some of the cases the safety setup was very far from optimal).

At the VWT accidents the applied safety measures proved to work well.

EDIT: ah, redundant post - Bill already wrote it all

 

[fcallagy]

Thanks Bill, I still dont understand why herberts cone is not de rigeur at present and would ask can we leave Adels case to one side and not comment on it. Its still very fresh to many of his friends here and think we should respect that but I do understand this discussion needs to be had . I am surprised we have had no comment from any of the famous nlt divers yet with their views.

 

[Will]

It's misguiding to say that because, for example, someone made an error while narced and nervous at 100m then the safety guidelines weren't followed. At the end of the day, in each of the incidents the contemporary safety systems were in place, and whether through human/mechanical/other error they proved insufficient. Ergo VWT/NLT is far more dangerous than the athletic disciplines, where numerous human/mechanical/other errors have never led to fatalities.
The historical precedent is that improvements in safety have not slowed the incidence of fatalities and serious incidents in sled diving - in fact the statistics suggest the opposite.

the athlete, when it comes to sled-diving, should not be able to disconnect himself from the dive line.

Really? Consider if a ghost line drifted across the path of the descent line. Then the athlete would be trapped at depth by their lanyard, and counterballast wouldn't bring them up.

talking about deep water bo's in CWT, everything deeper than 25 is fu## deep in Constant and we have not soo few of those.

Yes, 25m is "fu## deep" for a BO, but a safety freediver can potentially bring someone up from 25m. The same cannot always be said for 35m+, and there haven't been ANY blackouts this deep in CWT/CNF/FIM, while they are commonplace in VWT.

Regarding statistics, again, I can't say this any more succinctly than in post #150. Although the document analyses official dives (there is no data on training dives), the ratio of official:training dives will be similar between sled disciplines and the other disciplines, and this is the important point that validates the method of statistical analysis - the measure used is impartial and representative. Even if the ratio of official:training dives varies by 10-50%, this error margin would be swamped by the enormity of the difference in end relative risk values between sled and other disciplines.

 

[osusim]

We can easily compare women CWT around 100m and women VWT around 125m. How many attempts were done, how many BO's, how many very-very deep BO's, how many lung squeezes?

 

[Will]

We can easily compare women CWT around 100m and women VWT around 125m. How many attempts were done, how many BO's, how many very-very deep BO's, how many lung squeezes?

From memory,

how many attempts were done?
CWT: 5
VWT: 3

how many BO's
CWT: 3
VWT: 2

how many very-very deep BO's with consequent lung squeeze?
CWT: 0
VWT: 2

how many times was CPR required for resuscitation?
CWT: 0
VWT: 2

 

[mattbigblue]

eh,

Will, it looks like it is just banging Your head against concrete wall :head
noone is listening.
There are thousands of CWT/FIM/CNF training dives and ratio of accident is 0:xxxxxxxxxxxxxxxxx!

There is only few of accidents in VWT/NL because luckily there is not much serious interest going on. Just imagine if VWT/NL would be same popular as CWT/FIM/CNF, and if we would have xxxxxxxxx people training and diving VWT/NT everyday, I bet my money that everyday we would loose at least 1 diver.

 

[efattah]

Bill,

Is it true that Simoni from New Caledonia required CPR at Sardinia in 1998 after a deep BO on a 58m CW dive? That is, I believe, the only time I ever heard that a constant weight diver needed CPR, but I am not sure if the story is true.

 

[Rik]

I don't know about Simoni, but I do know that prof Data presented a study in 1986 on diving and electrocardiography. Several of the divers got an arythmia, and one of them needed to get full CPR. Not just rescue breaths, but breaths AND compression. This was not caused by an black-out, but an arrhythmia induced ventricular fibrillation. This was an Constant Weight or Free Immersion style dive to just 23 meters of only 118 seconds. The whole article can be found in UHMS workshop The Physiology of Breath-Hold Diving book in 1987.

 

[trullalla]

off topic, but i see people wondering about anna accident, so, sincei was there:
she blacked out at 40m, brought up with 2 safety divers and a uw scooter.
once on the surface she was given 6 rescue breaths and since that wasn't enough to make her start breathing again, she was moved on the platform where the doctor started CPR.
she started breathing after 1 minute and 25 seconds after she broke the surface. (so all in all a total BO duration of 2 minutes).
she had a bad squeeze and she was taken to the recompression chamber where she was given some tests.
she's ok now.

she had been training vw and nl since april, so it wasn't unreasonable for her to try that kind of depth.
previously she had done i think 120 m in VW not long before his official attempt. she had done 125 mt in NL 10 days or so before, so her mouthfill was cured (she did all these dives with a mask on). no squeeze before.

i personally think that the UW scooter deep safety was a great tool to have and that it made the rescue to be easier to perform (the safety diver was at around 60). today we actually decided that we're going to get one for FDD and use it from now on for all our competitions, at least for the deep dives.

linda

 

[Mullins]

How do you bring divers up with the scooter, Linda - clip a line onto their lanyard and tow them?

 

[Simos]

I read this tread with big interest, this even if some of the tread-contributors makes me wonder if they ever done freediving.

Even if this was true, how freediving is perceived by people who don't freedive is highly relevant here. Same for some (like me) who freedive, are AIDA members but are relative beginners - we're all affected, others more, others less. I would be more worried IF (and I don't know this, hopefully won't be the case) whoever are in charge of making the right decision here take decisions not in the best interest of freediving as a sport, but for their personal reasons (e.g. they are after a WR in NLT).

AIDA could/should sets stricter standards when it comes to sled-diving-trainings, but this standards would only work if they will be followed.

Bill don't you think that it's also important for AIDA to have a strategy for how to ensure that standards are followed? I'm not saying it's easy but if that's the problem here (which I don't think it's the only one) surely this should be a focus for AIDA. It's a bit like having a law that bans drinking and driving, but having lots of people drink and drive and lots of fatalities and being content that the law is there (which I have seen in certain countries).

Sure, there will always be people that take silly risks that are obvious to everyone but even for that, there are things that can be done - if AIDA doesn't feel someone is acting in a responsible enough manner and following safety guidelines, maybe AIDA should not be associated with that person. I'm sure if one of the SCUBA associations would strike off an instructor that chose to dive in a risky way and not follow their safety guidelines, or at least investigate it. (not sure if AIDA does that but seems to be that it is considered the individual's problem if the standard's are not met).

In terms of the sled-diving guidelines - I am assuming you are referring to this document? Downloads - Aida guidelines for sled diving.pdf

Apologies if that's not the right document. If it is, surely it's better than having no guidelines whatsoever and a good start based on no-doubt lots of experience by some of the pioneers of freediving, but do you truly feel that this is adequate or up to date? My feeling reading it (as someone who has done almost no sled diving) is that there are a lot of general points on what should be done but doesn't explain HOW (e.g. a proper safety system should be there etc). It talks about inflatable lifting devices, yet there seems to be a preference from top freedivers of not using an inflatable lift device.

I am only making these points constructively, and maybe a bit as an 'outsider' in the sense that I'll never be someone who will compete at high level or achieve anything significant in freediving performances (although I do love freediving and I am really interested in constantly learning).

But I feel that we would be turning a blind eye if we didn't at least acknowledge that there is a healthy discussion to be had on this - whether it ends up in NLT/VWT being removed from AIDA or not, I am sure it will at least end up improving things. Already some people have shared some good ideas that don't seem too hard to implement.

Particularly interested in hearing your honest assessment on the above on these as an ex-president of AIDA.

 

[kelp princess]

"Accordingly, the AIDA Board recommends that" -- comment means that Aida Board can recommend but not to decide this level decisions. In that same email, which I mentioned, it says that Aida Assembly has their responsibility on this matter as Aida Assembly is the highest decision making function in Aida International. This fact is based on Aida Statutes (https://www.aidainternational.org/downloads/3-statutes) which we all have agreed to respect in Aida. Despite our own emotions, opinions and feelings.

Democracy is not the easiest way to govern the organizations. Sometimes it may not be the best way neither, but we have chosen that way in Aida and this is the reason that these decisions will be made with democracy.

Sorry again this kind off topic comment but also my clumsy text. I´m not quite good to express my thoughts in English.

Yours Sincerely,

Kimmo Lahtinen
AIDA, president

Hi Kimmo - thank you for sharing this information and i must say that actually your english is fine and you do get your points across very well.

cheers,

kp

 

[Walrus]

Despite this being counter productive to my previous posts:- I do know of 2 cases where a CWT or FIM blackout resulted in the diver needing at least 2 minutes of mouth to mouth resuscitation. One I was told about fairly 1st hand so know it was pretty accurate, the other was very diluted so don’t know the exact details. Luckily they are both ok, one of the divers was banned by AIDA from competing for a year. Not sure if it was AIDA Int'l board or the National one.

Cheers,
Wal

 

[chrismar]

While Herbert's incompressible cone is a good idea, I suspect that it hasn't been adopted because:
It's expensive
It's hard to make
It relies on ditching a large amount of weight, so a clip failure would be fatal
If it cracked you'd have no buoyancy
There are relatively few people going deep on sleds

Herbert's setup also used a platform with redundant very powerful electric motors to pull up the line. Again, a very good system but again very expensive. At the end of the day, no limits requires a very large financial outlay to improve safety. That limits the people who can do it not to those with the ability but instead to those with the money.

I've dived with Anna and she is very safety aware. The fact that she had to get rescued from 40m by someone on a scooter is concerning. I also suspect that most of those saying that number of people that have died in sled dives isn't so high and therefore the risk is acceptable probably aren't the ones who knew Adel, Loic, Anna or others we've lost or almost lost.

 

[mystiach]

A lot of this debate has centered around 'acceptable risk'. What is acceptable for some is not for others, and as Chris pointed out, knowing one of the people involved often brings the statistics into a new perspective.

Without major changes, there will be more accidents and incidents until there will be a point where people will have to admit that sleds are inherently risky. Unfortunately at an international level this takes a long time to catch on and for the bureaucratic cogs to start turning. Even more unfortunately this always happens at the expense of someone's wellbeing or life.

There is a genuine opportunity to intervene now and prevent any incidents for the future, because irrespective of whether sleds remain in the sport it will send a clear message to AIDA international that its members are not satisfied with the current situation. Otherwise, without significant change, the same debate will simply happen over again in the future.

 

[Unclejake]

There is a genuine opportunity to intervene NOW and prevent any incidents for the future.

I wish it was like that, but the strongest thing AIDA can do is to stop recognising the sled dives.

The rest of the responsibility is the diver's.