What is the deepest you can do an OOA?

[airsix]

...One thing I do know is that feeling comfortable being able to do a CESA from 30-40’ goes a long way to reducing overall anxiety in a lot of divers once they realize they can survive a worst case scenario....My attitude about CESA practice is about the same as thinking the FAA screwed up when they stopped requiring commercial pilots to do spins. A CESA is what you do when everything goes wrong and you need the confidence to maintain your cool, just as a spin is what happens when a stall goes wrong and no one should ever be in a position they’re surprised.

That's exactly what I've been trying to say. Thank you for saying it better.

-Ben

ps - I can't believe spin recovery is no longer trained! What the #$*& are they thinking? That's just unbelievable. You have to practice it to know it. You can't be expected to do it right in an emergency based on book knowledge of the procedure. Like CESA, it's not intuitive until you've done it.

pps - I loved spin recovery training.

 

[H2Andy]

ps - I can't believe spin recovery is no longer trained!

nope ... but any good instructor will take you out and do it with you

 

[adza]

Mentally I’d rather think of it as “when” rather than if just as I assume the engine’s going to stop on every takeoff so I can be pleasantly surprised to get at altitude rather than make a forced landing

Well put. I guess I have gotten lazy after having so many incident free flights. It never hurts to be reminded to always plan for the worst. Thanks for the pick-up!

Do I get extra credit for 5 engine failures in one flight – in a single engine aircraft?

Now that would have to be one story to tell! And you managed to get the engine restarted every time, or just 4/5? ;-)

 

[Gary D.]

Noone seems to mention that the metabolic rate of the diver at the time of the OOA is a huge issue. It is easy to simply "float up" from 60 feet and not breath for 45 seconds if you are bouyant, relaxed and your heart rate is at a resting pace. I did it as part of the basic PADI course when I was 13, in 40 degree water and was terrified, but I did it. But what if you are tired, cold, scared? Your heart rate will be much higher and the consumption of oxygen will be much, much higher. Plus the diver may already have accrued somewhat of an oxygen debt before the incident.

Practicing an OOA ascent while starting with full lungs is unrealistic. You aren't gonna know you are outta air until you can't inhale..so start out with no air in your lungs and practice the CESA after swimming hard for a few minutes.. think the magic expanding air will make you feel wonderful?

The CESA is not a viable option for most sport divers below about 60 feet, MAX

If you have “No Air” in your lungs you have some much bigger problems than just running out of air. The lungs are never empty without parking something like a steam roller on your chest.

I will use the Navy as an example. The object of the dive school used to be to make you quit. If they couldn’t the days got tougher and tougher and the fail rate was extremely high.

At first they would pull your air AFTER you took a breath. Later in training the air went away on an exhale. So you try and fool Mother Nature or at least the instructors by only exhaling say 60 or 70%. Well, you can only do that for so long and they knew that. When you finally did relax and exhale you could say by-by to your air supply. If you didn’t expect a fist or knee in the gut.

If you surfaced you’re out, done, history and headed back for another command not as a diver.

People need to quit trying to over think this process. All it does is get minds trying to figure out ways that it won’t or can’t work when in fact it works very well.

We survived these over and over again in cold water as well as warm, with and without exposure suits, the BC still meant Before Christ, full and lesser lung volume, with and without masks, with and without fins and none of the fancy color coordinated redundant gear so many need today.

Thinking a pony or having a second tank available somewhere is going to make you 100% safe is like thinking you can’t get hurt or killed because you have a seatbelt and airbag. Your chances can still be greatly improved by knowing and practicing defensive driving. It’s no different than Diving.

Gary D.

 

[JS1scuba]

People who are OOA head for air. My nearest air will almost certainly, barring a complete disaster, be on my buddy's back. I think my time is much better spent practicing air-sharing procedures and good buddy awareness and positioning and underwater communication than practicing CESA.

Actually people who are out of air do not head for air they make a b-line for the thing that YOU are breathing from. They lose complete regard for you. They take the thing that is in your face cause they know it is what is working. There is no stoppping to signal "i'm out of care can i have some of yours" it's a hit and run with such force it will knock you for a loop. IT is this reaction that has made the long hose and necklace regulator under the neck such a reasonable and perfect set up. To take it a step further put your mask strap under your hood and you are now better protected.

Practicing is important. Diving with responsible people is important. But someday and that day will come you will be the victim of being a donor to an OOA situation.

Be prepared ........

cheers

 

[FredT]

dude, with your diving style, you're lucky to be alive

Good training helped a lot. The best single piece of advice my instructor gave me was "When the world turns brown think the word "PANIC", and you won't.

That single thought is enough to remind you that if you panic you die. Generally this the the non-preferred option. It's almost always easier to to deal with the situation in place than to panic and drown. The ONLY times in well over 5000 hours under water where "bolt to the surface" was the correct answer are detailed above.

Spend enough time under water and eventually you'll have a brown day. Mother Ocean is a hungry wench who WILL be fed. Your job is to delay her meal as long as possible, and encourage her to simply take light snacks along the way.

Normally I dive relativly conservativly. Those 2 incidents involve over 38 years of active diving.

FT

 

[friscuba]

I thought it was buildup of CO2 in the body (or probably the brain), not the content of/volume in the lungs.
My knowledge of basic gas phenomena is fine. It is the human body I'm trying to understand.

I could be very wrong, but freedivers show us that the CO2 buildup takes at least a little while before the buildup is enough that you absolutley have to inhale. A lot of it is psychological. We get a lot of students who think you have to inhale the moment you stop exhaling in their normal breathing pattern, yet that's not how they normally breathe above water, takes a bit to get over it... in the case of going up and always having a fairly full set of lungs, it's probably a lot easier to not have the urge to inhale.

I've certified a few guys who are now well into their 60's and beyond who said they had to do a 90'+ CESA in a tower for the Navy. My 78 year old uncle was taking about having to do it every year or so for years (career submariner). He said they finally went to the hood I've seen mentioned earlier. Those I've talked to about it said nobody ever didn't make the 90', lots didn't want to try, but they all made it.

 

[adza]

Thinking a pony or having a second tank available somewhere is going to make you 100% safe is like thinking you can’t get hurt or killed because you have a seatbelt and airbag. Your chances can still be greatly improved by knowing and practicing defensive driving. It’s no different than Diving.

Gary D.

Gary - that is a brilliant example! Mind if I use it?

 

[diebeste]

Well, then were talking a controlled swimming emergency ascent and that shouldnt be done from more than 60 feet..

Well, I am sure that any one in an OOA situation deeper than 60 feet will still try to reach the surface anyway. The deepest unassisted freedives are much deeper that 20m, and that is with the lungs filled at 1 ATM. YMMV depending on how full your lungs are at the time, but I think that in a real emergency you will be surprised what you can do.

And lets not forget the last option in OOA recovery - the bouyant ascent. Compared to breathing pure H2O, still a safer option.

 

[cerich]

..and the key here is NOT breathing compressed gas.

SETT escapes at ambient.

SCUBA is totally different with breathing compressed gas and spending a considerable time at depth doing it.

It is compressed gas, just because you aren't breathing from a scuba tank doesn't mean it isn't compressed. I promise you you aren't getting the top of the escape tower open at 100 ft unless the air under the dome (that you are breathing) is compressed to ambient by the ingress of water.

BTW, the air you breath while on scuba is also at ambient.