What is the deepest you can do an OOA?

[dumpsterDiver]

Training many sport divers in the proper use of pony bottles or doubles and getting them to go through the hassle of safely using them is not always viable either so maybe we should not allow sport divers past 60’.

I personally won't go past 60 without a pony and I can snorkel that deep and shoot a fish while I'm there. I think divers should be allowed to do what they want, but I think there is a huge false sense of security expressed by some people about the viability of a CESA.

I'm not sure that a lot of training is required for the use of a pony, although it is probably good to practice using it and rig it so that you don't get the pony and the primary mixed up.


I also think it is funny that people on this board will say that a 13 cuft pony is too small for diving to 130 feet and then other, seemingly rational people, will argue that you can ascend from 130 feet at a leisurly pace with ZERO air.

 

[FredT]

Why would you allow yourself to be in that position?

Scenario one:
Diving for bugs, 132' ledge with a 72. UP to my armpit in a hole and breathing "easy" with one hand almost around an antenna knuckle of a Volkswagen. I breathed right past the hard inhale warning by breathing very slow, and the J had already been rolled down by the ledge (unknown to me). Exhaled completely then tried to inhale and oil canned the tank. 132' straight up, after getting my arm out of the Volkswagen's hole. NOT bent, or at least not so I noticed in the adrenalin rush.

For the uninitiated you never know you're OUT of air until you try to inhale and get nothing. An OOA ascent ALWAYS BEGINS at the bottom of you lung's tidal volume. Some air management is necessary on the way up. Just open the throat and let it expand as it wants to for the first few feet.

Scenario Two:
While diving in a HDR on a deep rig I shot a large AJ that tried to take me to the bottom in about 800' of water. During the fight I killed a bristle worm by crushing it with the inside of my left arm. Suddenly I was at 160' with 3/4s of a tank of air, and no way to inhale. The bristle worm is a neurotoxin carrier and I got enough of a dose to effectively paralyze my diaphragm and most of the rest of me. I had already filled the BC with about 80 pounds of lift so when I let go of the gun I caught the express elevator to the surface. Total dive time was under 5 minutes., The ascent portion of that was under 15 seconds. Luckily I missed the cross members on the way up, and the sea was rolling enough it helped me breathe a bit. It took about 15 minutes before the toxin started to wear off. My buddy came up in a much more controlled manner while trying to figure out how to tell my wife he'd "lost" me.

Both are posted in much more detail elsewhere on this and other boards.

The world can turn brown REALLY FAST!

FT

 

[dumpsterDiver]

I didn't know those worms could do that. Are you unusually alergic or something?

 

[H2Andy]

oh never mind ...

it's like arguing you must know how to put out a fire with your bare hands in case your crack pipe catches your clothes on fire

 

[FredT]

nope. But the worm my buddy saw drifting down was over a foot long and well mangled. The arm healed to the point the welt wasn't noticeable in about 6 weeks

 

[H2Andy]

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

 

[adza]

Bill51. Thanks very much for that informative reply. I like the idea of doing 50" CESA's 'for giggles' or as practises (while monitoring your ascent rate to make sure you're not taking any unnecessary risks).

It's one thing to do it once during the OW course - but totally another thing to have done it often enough to be comfortable in an emergency. (Similar to forced landings in aviation. The more 'practice' ones you do - the more conformtable you'll be if the situation arises.

 

[Bill51]

oh never mind ...

it's like arguing you must know how to put out a fire with your bare hands in case your crack pipe catches your clothes on fire

Now I know where you get your comic talents.

 

[Bill51]

Bill51. Thanks very much for that informative reply. I like the idea of doing 50" CESA's 'for giggles' or as practises (while monitoring your ascent rate to make sure you're not taking any unnecessary risks).

It's one thing to do it once during the OW course - but totally another thing to have done it often enough to be comfortable in an emergency. (Similar to forced landings in aviation. The more 'practice' ones you do - the more conformtable you'll be if the situation arises.

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 – most of the time. I don’t like unpleasant surprises like the engine coming to a sudden stop at 75’ just as the gear locks up. Just because I’m flying a twin doesn’t mean I shouldn’t pull the engines back on baseleg occasionally just to see what it takes to make the runway. I don’t want to be totally dependent on any backup mechanical system all the time – only on those special occasions, like caves, where you must extensively plan for it.

I would never recommend doing CESA practices deeper than 50’ – not that I don’t think they can be safely done, but sometimes you get a nasty CO2 headache from deeper ascents that may not be a real injury but they do hurt for a few hours.

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

 

[String]

Call HMS Dolphin in Gosport and see how many AGE from CESA they have had, you'll be shocked to find very,very few, mostly eardrum issues. They train 30M free assents all day....

..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.