Free flow at 94' ffw

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Good job homie, stay safe out there. That water sounds cold as hell! I agree with you, I've found it's always a great idea to have redundant air sources... whether that be sidemount and 2 tanks for recreational diving, or at least just having a pony bottle. Real life is much different than the classroom, and you're right there's always gonna be armchair divers who think they're the next Kevin Costner from The Guardian movie lol.

You pretty much did the right thing, I can't think of anything I would have done differently if I were you. I might have briefly waved over at my friends or signaled, but in murky water, they probably won't see anything anyway, let's be honest. As for regs, I know other people will have different experiences but I've personally found the good ScubaPro regs have never failed me and they work pretty smoothly.
 
As far as detune and predive in my alternate I do that so to help it keep from being too sensitive but only on my alternate, if I am not understanding what you are trying to say here, my apologies. I am not a reg tech and don't set my own IP's however I have thought about getting the tools and training in the future.
My weight is good, I dive a couple pounds over weight 2-3 but for me I like it because I don't like to be on the raged edge of weighting when I am in bulky undergarments but that's me. I was in black water so I had zero visual reference to my surroundings and really never would have expected my alternate to be the one that went into freeflow so when I felt air coming from around my neck my first thought was that it was air coming out of my neck seal. The reason I went vertical was that if it was my drysuit inflater malfunctioning it would continue to leave my neck seal and not fill my feet up with air and I end up breaching the surface like a backwards whale from 100'. As far as feeling a change in buoyancy I suppose its possible but with a full on freeflow blasting me in the face it was a bit disorienting and I was doing my best at problem solving and trying to calmly but quickly eliminate the possible issues at hand.
I think back about 30 years ago when I was a dive master in Canada, doing and having same results. I didn't know what I didn't know. I truly feel that some more comprehensive knowledge of how your equipment works will be useful
 
Heya Tony,

Kudos for posting this. We can all learn from incidents like this, and yes we might analyse and give our opinion but in the end it's easy to do so from an armchair... it's a bit more difficult when you are at 100' in pitch black darkness and suddenly you hear loud noise and loads of bubbles! I think you did great!

Let's start with an ideal "textbook" scenario (which depends on training and setup)

1 - COLD WATER suddenly LOUD NOISE... BUBBLES? First thought is freeflow, 2nd is freeflow of buddy, 3rd is banged valve (valve failure), then very distant other things like stuck inflator of drysuit or wing.
2 - CHECK SOURCE OF NOISE: Where are the bubbles coming from can I see them? If it's my breathing reg, switch reg to backup (not because you can't breath a freeflowing reg, but because you can't see very well with all those bubbles in front of your mask).
3 - SIGNAL TEAM
4 - CLOSE VALVE of freeflowing reg.
5 - CHECK GAS and evaluate options, which could be calling the dive, or reopening the valve after a minute or 2 to see if the freeflow continues.

So now to your incident (and please take this not as critique I think you did great!):
1 - When in cold water, hearing a loud bubbling noise always first suspect a freeflow, because that is the most logical scenario. Stuck inflator will not bubble like this and you will immediately feel this because you will get very buyoant very soon. Same with bcd/wing.

2- You had redundant air/gas sources available (a pony and 2 regs on your tank). Very good! I don't know if the 2 regs on your main tank were fully separate (on a H or Y valve with 2 x 1st stage and 2x 2nd stage or 1 valve and one 1st stage and a main+Octopus). If you are not diving manifolded doubles (and can close the valves) diving a Pony in cold water is a very sound strategy! It keeps you in control of an alternative air/gas source and gives you options. In the end you didn't need the pony because you were already at the surface because of your quick reaction but having this available is very good idea.

3- Signal buddies. You didn't and decided signalling in the bad vis would only cause confusion. You could be very right... I once in a similar scenario signaled a buddy to warn him of my freeflow. I was diving a single tank with separated valves/regs. In the bad vis he noticed I had a freeflow, but didn't check really well which reg. I switched to my backup reg (main was freeflowing), he swam behind me to close the valve of the freeflowing reg but instead closed the valve of the backup reg in my mouth. I had no way of signaling him (he was behind me) so the only option was going to the freeflowing reg and breathing from that. I can tell you that was a really hairy moment. That being said, signalling buddies is still a good idea, because they are in worst case scenario your alternative airsource!

4- Close valve: Since you use a pony, closing a valve is not a skill that is imperative, you have an alternative source. However if you don't and there is a chance of freeflow (cold water, current) being able to secure your air/gas source becomes important.

Finally somethings that aren't really mentioned yet. How can you prevent a freeflow?

- Regs: Some regs are more prone to cold water freeflows than others. I don't want to start a discussion but IMO closed membrane regs are better than open piston regs, because no water is touching the inner parts of the 1st stage.
- Separate usage: You have 3 main usage points. The reg you are breathing from, your drysuit inflation and your bcd/wing inflation. Make sure that they are not all on the same 1st stage if possible. This will limit the demand (gas flow) on your 1st stage. Think maybe about separating those 3 (and the backup reg) on 2 different 1st stages.
- Check tank and gas: Make sure your tank is clean, even small particles (oil/water) can function as nuclea for freezing.
- Dry regs: Make sure your regs are dry and specially if the surface temp is below freezing, don't prebreath your reg on the surface (out of the water), don't put your gear in snow, etc.

Just some comments, but like I said, I'm very happy that you posted in the incidents forum. Lots of people read this and can learn from your experience, specially the things you did very well.

Cheers

B
 
I must have missed it, but what size pony id you carry ?
 
https://www.shearwater.com/products/peregrine/

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