Is this video real? 293ft on air...

[SkimFisher]

Why is it so hard to believe?

 

[drbill]

What I DO know, is that diving to 200 feet on air is a muy muy malo idea.. Diving to 300?? That's just plain loco, amigo.

I've done quite a number of deep air dives to 200' on air and even averaged 180 ft on three dives a few years ago. While I don't recommend such diving to anyone else, deep diving on air was not that unusual back in the era I started diving (although I didn't do it in the 60s... I waited til the mid-2000s).

 

[captain]

Someone once told me you can artificially make your computer read much deeper depths by setting it in altititude mode and diving at sea level.

If he really did got to 293 feet on air, I would have thought that the biggest problem would be that even on a high performance regulator, that would be like trying to breathe glue.

Cousteau's team dived the Britanic in 1975 on single stage Le Spirotechnique Mistral double hose regulators using a He mix. A bit less dense than air but using a rather simple regulator.

 

[Walter]

When I learned to dive, we were not taught a limit of 1.4 or 1.6 atm partial pressure of oxygen, but 2.0. That happens on air at 297 feet.

 

[mafiajoe]

Why is it so hard to believe?

Something I was about to ask myself.
What's all this fuss about? A 89m. dive on air,so what?
And what does it have to do with snorkel,fins type and B/P?
That dive is perfectly doable with any kind of gear and a normal BCD....even without a BCD.

 

[Rhone Man]

Cousteau's team dived the Britanic in 1975 on single stage Le Spirotechnique Mistral double hose regulators using a He mix. A bit less dense than air but using a rather simple regulator.

I have never breathed it, but I gather Helium is significantly less dense than air. When David Shaw was diving to 900 feet breathing a 96% Helium mix, I remember reading it was the equivalent of breathing air at around 150 feet or so (no doubt someone will correct me if I have got my sums wrong). The Brittanic is a 'meagre' 400 or so feet deep. Very impressive what Cousteau and his team did given the limits of technology of their day, but I don't think it undermines the point about air getting very thick to breathe below 200 feet.

 

[Cave Diver]

Why didn't they just go 7 more feet to make it an even 300?

Because he was obviously smart enough to know what his limit was in regards to gas supply, deco time, PO2 tolerance, narcosis, etc. and refused to break that. You shouldn't encourage people to push past their comfort zone just to reach some "glory number."








<snicker>

 

[captain]

I have never breathed it, but I gather Helium is significantly less dense than air. When David Shaw was diving to 900 feet breathing a 96% Helium mix, I remember reading it was the equivalent of breathing air at around 150 feet or so (no doubt someone will correct me if I have got my sums wrong). The Brittanic is a 'meagre' 400 or so feet deep. Very impressive what Cousteau and his team did given the limits of technology of their day, but I don't think it undermines the point about air getting very thick to breathe below 200 feet.

As the valve is the limiting choke point in most cases I don't think the type requlator is a major concern. Just the act of breathing air at 300' through a regulator or not adds increased effort to the act of breathing.

 

[Akimbo]

Sure, thousands of US Navy first class divers are living proof. We all went to 298' on air and 60' on pure O2 as part of the training. Granted, it was under very controlled conditions. As I recall, counting to ten and figuring out the difference between our exhaust and air control valves was about the most anyone of us could handle at 298'. It's a good thing it was in a wet pot in the Washington Navy Yard instead of the open sea.

A PPO2 of 2.0 is not the magic point where all humans instantly experience Oxygen toxicity, there is a lot of individual and environmental variability. Emergency escapes from submarines have been made far deeper than that on air.

I have not seen scientific data to back this up but I, and many others, find that repeated deep air dives substantially increased our tolerance to Nitrogen Narcosis. I doubt this was the first deep air jumps for the guys in the video.

Let's not even talk about military swimmers who survive circumstances that force them deep on pure O2 rebreathers &#8212; let's see; killed for sure versus maybe taking O2 hit&#8230; stuff happens to these guys. I have not seen anyone using Hannes Keller's aggressive decompression schedules in the real world either. If guidelines for O2 tolerance and decompression were that close to the margin of the average population, a lot of would be dead or damaged.

All this said, it is not a very good idea outside of extreme emergencies given the more prudent options available. Definitely a high risk form of entertainment. Dives like that without a chamber on site is the greatest risk IMHO.

 

[diver 85]

At least he had a snorkle with him... just in case!

:cool2:

was noticing that too---good diver(s) in my book....