Diving and flying

[justinthedeeps]

One of the Navy tables

 

[justinthedeeps]

Ascent to altitude as a function of Buhlmann decompression models
Can we calculate no-fly-times? – The Theoretical Diver

 

[Seaweed Doc]

If you want to add just a touch more to the safety margin, you could breathe down any nitrox left in your tank to whatever the dive op allows while on the boat ride back.

 

[tursiops]

Here is the DAN Workshop report on which the current Flying after Diving recommendations are based.

 

[Altamira]

As a retired AF and commercial airline pilot, I am always amazed at how many divers are trying to figure out how close they can fudge the DAN guidance on dive/fly intervals. The thing too many divers do not adequately understand about the risks involved in shaving the dive/fly guidance is the fact that when we are flying as a passenger on a commercial aircraft, we have ZERO INPUT or CONTROL as to what altitude profile the airplane might actually achieve during the flight, or what the Captain choses to do with the aircraft. You might be OK and not get bent when you fudge the dive/fly interval if everything goes as planned during the flight. But, throw in an inflight emergency such as a rapid cabin depressurization, when your body goes from @8000' cabin pressure, as is common on most modern jet liners flying at high altitude, to 30,000+ feet cabin pressure in a matter of seconds, and you will be royally screwed. I know very well how quickly things can go sideways inflight, so I never press the dive/fly intervals.

 

[Sbiriguda]

My naive question was the beginning of a wonderful thread

I assume the short answer to my question is: NO, JUST STICK TO THE RULES

But some of your answers are full of important remarks I didn't find (or perhaps I missed) when I learnt the rules

 

[Sbiriguda]

The diving you describe here is well within the US Navy limits, and it is within the PADI and DAN America recommendations. It is outside the DAN Europe recommendations, which are very conservative.

That is not good, I didn't notice that DAN Europe has such very strict recommendations that go beyond PADI and DAN America. In theory, if PADI and DAN America consider this type of dive safe, nothing should happen. But if something does happen, I suspect DAN Europe would not pay the very high expenses for the hyperbaric chamber because the dive was outside its own standards. So the best would be to apply the DAN Europe recommendations...

 

[boulderjohn]

That is not good, I didn't notice that DAN Europe has such very strict recommendations that go beyond PADI and DAN America. In theory, if PADI and DAN America consider this type of dive safe, nothing should happen. But if something does happen, I suspect DAN Europe would not pay the very high expenses for the hyperbaric chamber because the dive was outside its own standards. So the best would be to apply the DAN Europe recommendations...

You can check that, but I don't believe that is true. I think they will pay.

 

[Sbiriguda]

Well, if you dive with a CC pure oxygen rebreather (ARO) you will not get any Nitrogen added.
Current recommendations are to not exceed 6m depth with these units, albeit I am certified for using them down to 10m.
When young, I and my wife did use them several times down to 12m, with the trick of starting with
the counterlung full of air, instead of pure oxygen.
CC Rebreathers require specific training, but can be the solution for your problem.
You could also consider Nitrox at 50% in OC.
It has a maximum depth of 22m (at ppO2=1.6 bar), but you should stay much shallower if you want to keep the ppN2 as the same value as atmospheric air, that is 0.78 bar. You reach this pp at approximately 6 m.

Thanks for this post too
The advantage of scuba diving in a dive as shallow as 6 meters deep is probably on underwater photography. Otherwise one could just do snorkeling and freediving. As for freediving, I dislike the idea to do that without buddy which I also consider unsafe.
I am interested in ARO maybe one day I will try one of the courses. Still, it has become more and more difficult to find both the gear and the instructors or courses

 

[Sbiriguda]

As a retired AF and commercial airline pilot, I am always amazed at how many divers are trying to figure out how close they can fudge the DAN guidance on dive/fly intervals. The thing too many divers do not adequately understand about the risks involved in shaving the dive/fly guidance is the fact that when we are flying as a passenger on a commercial aircraft, we have ZERO INPUT or CONTROL as to what altitude profile the airplane might actually achieve during the flight, or what the Captain choses to do with the aircraft. You might be OK and not get bent when you fudge the dive/fly interval if everything goes as planned during the flight. But, throw in an inflight emergency such as a rapid cabin depressurization, when your body goes from @8000' cabin pressure, as is common on most modern jet liners flying at high altitude, to 30,000+ feet cabin pressure in a matter of seconds, and you will be royally screwed. I know very well how quickly things can go sideways inflight, so I never press the dive/fly intervals.

Ehm... ok now that you put it this way I FULLY understand your point