How deep can you do a CESA and survive?

[Footslogger]

I did one from about 138 ft (according to my depth gauge) in 1971. Was diving a J-valve rig and somehow the reserve lever got thrown ...probably on entry. Breathing got tough and I reached for the arming rod - - NOT !! Was wearing an old Air Force surplus horse collar at the time so grabbing a snort from the manual inflator wasn't an option. Toked the last cubic nanometer out of the tank and headed for the surface.

Made it (obviously) but wouldn't want to go for a do-over ...

 

[anzac65]

.......(The chamber opperator is on the inside of the boat and not in the pressurized area - now who runs the chamber for him? I guess he gets the Victoria Cross). .........

That would just be the George Cross.... presumably there's no-one inside the sub shooting at him whilst he (or she) is operating the chamber. They don't give VC's away that easily. BTW fascinating post, thanks.

 

[revrikki]

I know this is a thread on CESA, but I have read a few posts in it talking about ear clearing. If you are one of the unlucky ones who may have trouble clearing your ears, it may be a problem with your eustachian tubes that may be easily treated. You have two main muscles in your mouth that control the opening and closing of the tube opening.

WARNING! Long winded medical content follows!

The first controlls it directly, and that is the tensor veli palatini muscle. It's job is to open and close the tube to alow drainage and pressure equalization. If, however, this muscle becomes hyper tonic (overly tight) it will keep the tube open allowing bacteria to travel up and could cause a ear and or sinus infection. Secondly the medial pterygoid muscle needs to be pushed out of the way by tensor veli palatini msucle. Therfore, if the medial pterygoid is hypertonic it will not move out of the way and will not allow the tube to open, and this can cause all kinds of problems clearing your ears and giving you that stuffy feeling. Any divers living in the phoenix having this problem just give me a call and I will treat it pro bono. Only takes a couple of minutes. This may or may not be your problem with clearing your ears, but if it is I can treat it.

 

[jviehe]

Practicing the CESA is a very bad idea, much like practicing cutting your main chute and opening the reserve. You can kill yourself while youre practicing. You may exceed a safe ascent rate, not control your airway properly, or drown. I also disagree that students should be taught to actively open their airway while ascending. This is basic psychology. We want a student to easily recall a muscle memory during a panic situation. Making an ahh sound is much easier to remember than controling your airway.

The lesson you should come away with in regards to the CESA is that you should never have to do it. If you do, you have already screwed up royally by diving solo, losing your buddy, or not monitoring your air. Your first response in an out of air emergency should be to notify your buddy and try a normal breathing ascent. If that is not possible, share air and ascend.

 

[Gilldiver]

I found some more infor on the suit, I was off on the speed of accent from 180 meters, it is not 2 minutes but more like 1 minute ("a safe speed of approximately 2-3 metres per second").

http://www.rfdbeaufort.com/rfd_Defe...Id=28&categoryId=&subCategoryId=&productId=47
http://homepage.mac.com/frank.owen/SubRescue/PhotoAlbum3.html
And it looks like the US is making the mods to use it too.
http://images.google.com/imgres?img...=/images?q=seie+mk10&svnum=10&um=1&hl=en&sa=N


Product Description
The Submarine Escape and Immersion Equipment (SEIE)MK10 is designed to enable free ascent from a stricken submarine from depths down to 180 metres (600 ft) and to provide protection for the submariner on reaching the surface until rescued. The SEIE MK10 assembly comprises a submarine escape and immersion suit, an inner thermal liner, and a gas inflated singleseat liferaft, all contained in an outer protective stowage valise.


Features

The suit, which includes a stole and ascent hood, not only keeps the escapee dry and protected from cold shock during escape, but also acts as a thermally efficient immersion suit on reaching the surface. Full protection is therefore provided whilst deploying and boarding the liferaft. The suit with stole and ascent hood provides sufficient lifting force to take the escapee from the submarine to the surface at a safe speed of approximately 2-3 metres per second.

The SEIE MK10 is the result of substantial trials and tests including live ascents at sea from submarines and simulated escape from 200 metres. The Submarine Escape Training Tank (SETT) at HMS Dolphin and DERA Gosport have played key roles in working with Beaufort and MOD Navy (Technical Branch) in the development of the SEIE MK10 following introduction of the patented design. The system was fully approved, qualified and introduced into service by the Royal Navy in 1994.
The S.E.I.E. MK10 now sets the definitive global standard for submarine escape and survival equipment.

 

[fisherdvm]

The trick was to NOT to actively exhale or hum or aaaaah, but instead KEEP MY AIRWAY OPEN and let the excess air just kind of bubble out on its own.

The certifying agencies are taking a shortcut by teaching people to hum or aaaaaahhhhh all the way up, rather than teaching that what is important is an open airway, and then teaching people what that means.

Report of very slow 100' submarine escape training tower ascent


Charlie Allen

I think the reason to teach students to say "aaaaahhh" is to force them to consciously will the larynx to stay open.

This is especially when teaching new OW students basic pool skills - retrieving regulator, clearing the regulator, buddy breathing etc.

A panicked student who did not learn how to clear a regulator yet, will gulp and aspirate water. If he panics, his larynx is already reflexively closed. If he shoots to the surface, you would have an event like the death of the SSI OW water student 1 week ago at the University of Alabama.

If it is proven that this happened in the pool while his regulator was wet or out of the water, then it proves that simply saying "exhale constantly" while retrieving the reg is not adequate, and we have to emphasize the need for that guttoral "aaaahhhh".

When you vomit, swallow spit, accidently swallow water, etc. underwater, your larynx reflexively close. You need to consciously will this reflex to block it.

It is a different matter when a prepared scuba diver exit from a controlled CESA ---- his larynx is already open as it is dry.

You can not simply will your larynx to stay open when it is gagging from a flooded reg. You need to consciously say "ahhh", shhh, or whistle to get this to happen.

 

[fisherdvm]

I did one from about 138 ft (according to my depth gauge) in 1971. Was diving a J-valve rig and somehow the reserve lever got thrown ...probably on entry. Breathing got tough and I reached for the arming rod - - NOT !! Was wearing an old Air Force surplus horse collar at the time so grabbing a snort from the manual inflator wasn't an option. Toked the last cubic nanometer out of the tank and headed for the surface.

Made it (obviously) but wouldn't want to go for a do-over ...

That is amazing.

 

[Cacia]

Toked the last cubic nanometer out of the tank and headed for the surface.

...."ping"


running out of air is NOT funny, but it always makes me laugh.... It seems it usually goes better than you expect it too, with the volume expansion. Nothing like staring at the surface from the depths and wondering if you can make it.

 

[diver 85]

There's been a couple of comments about CESA lately and I had a question about it. I know that it's the very last option in an out-of-air situation, but I was wondering how deep you could be, use the CESA, and likely survive? Because whatever air you had left in your lungs is expanding as you ascend, would it make you feel like you had more air to exhale as you rise? Would you be able to blow out longer, say, than me sitting in my chair right now slowly blowing out a full breath? Just wondering.

100 feet or more, I would say.......And don't come back & say this is not possible or it's very dangerous........If you can get copies of the (old) made for tv series 'Ocean Quest' that Al Giddings made back in '85, you'll see where he 'trained' Shawn Weatherly(never had hardly a snorkle in her mouth before the series- A BRAND NEW NEOPHYTE....LOL) in diving & got her to make a 100' CESA( bleaux & geaux).....click the link for more info.......How many remember it???...My family & I do, we were taking private scuba lessons @ our house pool while it was being played weekly that late summer...I'm going to have to look for them because I taped every episode (seems like 4 were aired ).......

http://www.tv.com/oceanquest/show/7201/summary.html

 

[muddiver]

Charlie

Though I use the humming technique for CESA, please explain your airway method, more specifically how would you effectively teach it?

I think that is why for a BASIC SCUBA course, the majority of agencies use the hummm with your moth open description. :11: