Unexpected rapid ascent

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I'd check the schrader valve going into the BC(it's @ the end of your LP hose).....I've had sand get in mine causing the BC to inflate like you describe.....If it ever happens again, disconnect the LP hose & see if that 'helps'....
 
I will be adding hose pulling to my practice skills!
 
I have a question about what could have been done, not what caused the problem. If there was enough time to do so, would disconnecting the BC inflator hose have helped?

If the 1st stage was frozen open (as it appears) then disconnecting the inflator would have stopped the BCD from inflating but it wouldn't have stopped the free flow from the 2nd stages. If the freeflow is violent enough, which might have been the case here, ice can forum in the coupling that would make disconnecting the hose difficult.

Had it worked, doing so may have helped her to control her ascent more although what she did by swimming down and dumping the BCD is also effective to a point.

On that point, I have a question for ladyfishdvr. How were you dumping your BCD (pulling on an OPV or using the inflator hose). What was your position in the water at the time? Did you have the impression that the BCD was filling faster than it could be vented? I've been told that the engineering of the coupling acts as a restrictor that would stop the BCD from filling faster than it can be dumped. It seems that you have the opposite experience. Can you share your thoughts about that?

R..

---------- Post added May 12th, 2014 at 04:16 PM ----------

My last dive was two weeks prior to this one. I rinse in water and I am diving fresh water. It was my second dive of the day.

do you leave the 1st stage submerged in water for rinsing?

R..
 
bc inflator leaking and/or the schrader valve in the lp hose leaking through.2

A bad schrader valve exhibits as a leak when it is taken off the BC inflater, when attached it is fully open to provide air to the BC. If the o-ring sealing the inflater hose to the inflater connection it will bubble out around the connector. Sounds like the BC inflater, I just had a leak with mine but it was out around the inflation button. I doubt if you will find a problem with the reg other than it was in the wrong place at the wrong time and not properly dressed for the dance.

Good reactions ladyfishdvr.


Bob
--------------------------
I honestly feel I'm a better diver now. I learned to respect the ocean the hard way. One swallow at a time. Mark Derail
 
.. How were you dumping your BCD (pulling on an OPV or using the inflator hose). What was your position in the water at the time? Did you have the impression that the BCD was filling faster than it could be vented? I've been told that the engineering of the coupling acts as a restrictor that would stop the BCD from filling faster than it can be dumped. It seems that you have the opposite experience. Can you share your thoughts about that?

R..

---------- Post added May 12th, 2014 at 04:16 PM ----------



do you leave the 1st stage submerged in water for rinsing?

R..

I do not think the bc was filling faster than being vented but it was filling as i was venting. I "think" and this is blurry because it happened so quickly, I was trying to head down but started using the hose in my left hand to dump air so I could slow down and turn down, and it did not fill up as quickly but my regulator was also free flowing by then.

I dip my regulator and hang to dry.
 
Ladyfish,
If your bcd was self inflating, the thing to have done is disconnect the inflator hose. If for some reason this cannot be done immediately, hold the deflate button fully open while holding it HIGHER than the bcd, until the hose can be disconnected. Most deflators (I don't know about the Air-2) are designed so that they can vent air faster than the inflator can flow air into the bcd.

I have dived Dutch Springs, both with a Conshelf and a Mares MR-12 (essentially the same first stage) and the deep hole is pretty cold. But, even though a Conshelf is a diaphragm first stage, and is normally reliable at 40ish temps, the constant flow into your bcd likely caused it to freeze which was responsible your second stage freeflow. You tried your best to slow the ascent, which is commendable, but a rocket ride to the surface can be extremely dangerous.
 
Ladyfish,
If your bcd was self inflating, the thing to have done is disconnect the inflator hose. If for some reason this cannot be done immediately, hold the deflate button fully open while holding it HIGHER than the bcd, until the hose can be disconnected. Most deflators (I don't know about the Air-2) are designed so that they can vent air faster than the inflator can flow air into the bcd.

I have dived Dutch Springs, both with a Conshelf and a Mares MR-12 (essentially the same first stage) and the deep hole is pretty cold. But, even though a Conshelf is a diaphragm first stage, and is normally reliable at 40ish temps, the constant flow into your bcd likely caused it to freeze which was responsible your second stage freeflow. You tried your best to slow the ascent, which is commendable, but a rocket ride to the surface can be extremely dangerous.

Thanks. That is another good strategy to remember. I was not looking for a rocket ride to the surface, that's for sure. And when I did surface thinking "Well that was bad" I was waiting to see how bad it was going to be.

I was very very lucky. It also made me realize how quickly things can go bad, and even though I was diving with an experienced and attentive buddy, I was still on my own. I probably had about 20 seconds to react to prevent/delay the ascent, if that, which is not much time. I have also only been diving for a year with that being my 44th dive. I have a lot to learn but am thankful for the experienced divers who have helped me along the way whose advice was flying through my brain during this situation.
 
I dip my regulator and hang to dry.

It's not inconceivable that water can get into the regulator from rinsing if it's not under pressure. it may not be what caused your problem but it's worth considering.

What I do with mine is to just quickly rinse the hoses and avoid submerging it entirely. If you think about it, the only thing on the 1st stage that would theoretically be damaged by salt water might be the hoses.

I'm not even sure if that's neccessary tbh. Some people may disagree but I'd bet that if you never rinsed the 1st stage at all that it wouldn't make any difference.

R..
 
I only dive fresh water and I rinse because of the goose poop in the water. No salt water yet.
 
By the time I realized the bc was causing my ascent it was full. If I had realized that earlier I could have disconnected it and dumped air to stop my ascent but that did not click in my brain until I felt the squeeze on my ribs from the bc. and thats the moment my regulator began to free flow and I switched to the pony. I did not think to disconnect the BC hose, and I should have.

On the video it took 60 seconds from start to finish so I had little time to react.

---------- Post added May 12th, 2014 at 10:05 AM ----------



The pony was on the left and high. I had my hand on the air2 the entire time because the pony was there. It was not pressing on the inflator valve. I am happy I had the pony and plan to get my own for future dives.


+1 there I always have a redundant air system these days. Hope you get it sorted out.
 
https://www.shearwater.com/products/swift/

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