First open water dives with rebreather...
- Thread starter Aaron Harmon
- Start date
Please register or login
Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.
Benefits of registering include
- Ability to post and comment on topics and discussions.
- A Free photo gallery to share your dive photos with the world.
- You can make this box go away
I bailed off the loop multiple times during my first OW CCR dive. I was in the Keys (so, warm water and a thin wetsuit), but we were on Molasses Reef (35 - 40 feet deep) and there was a lot of surge washing us back and forth.
I was working, and nobody told me that a CCR with back mount counter lungs can be harder to breathe when you're in flat trim. I was being a good boy and staying flat - which made it hard(-ish) to breathe. I went to BO several times, just to catch my breath. I almost packed it in and quit CCR after that dive, too. I did pack it in for the day. My instructor offered to cancel the 2nd dive for the day and I took her up on that. She also gave me props for being willing to go to BO and not feel like I had to try and tough it out staying on the loop.
The next day, I figured out that cave trim (top of head even with top of fins) made it a LOT easier to breathe. Also, sea conditions were a bit calmer. I was fine (no more doubts about going CCR) after that.
Good for you that you didn't have that experience. I'm sure you're right that the rest of us just lacked basic dive skills when we started on CCR.
I don't think that's necessarily a fair assessment. For my wife and I, we both have 10 + years of technical diving experience and over 300 cave dives each. Neither of us are perfect divers (anybody that says they are is an idiot), but we're both squared away enough to not be embarassed by our skills in front of anyone and can handle real life issues and emergencies cleanly underwater. The big issue for both of us initially was buoyancy, which I think is true for most new ccr divers. We both read about how to manage the 3 bubbles and what to expect on ccr. The problem is you don't really understand it until you're diving it. I would make a minor adjustment in buoyancy and realize it was way too big. Or I would wait too long to make an adjustment, because it's so innate for me to use oc breathing for small buoyancy adjustments. So on ccr, my brain would say I'm a little buoyant so my response is to exhale and wait, by the time my stupid meter went off to remind me that's not going to work, I'd have to make a bigger gas dump than ideal. It was just an up and down battle at first trying to get used to it. For someone with alot of experience and comfort in the wate, it truly felt like I was back to being a new diver again.
I do agree with your thoughts a little though. I dove sidemount for many many years, but believe a bm rebreather is the only correct choice for a first time unit. I never took a formal doubles class, just learned through mentors. The rebreather pointed out that I understood, but not as well as I would like, how to adjust my harness and points of leverage such as fins to achieve perfect trim without having to work at it. My first couple of months on the unit I was trimmed out well, but was extending my feet out and arching my back more than I would like and led to some discomfort. I adjusted fins and harness tightness and got it fixed pretty quickly. But it also pushed me to take GUE fundies to really get an excellent mentorship in how to really work with those things. Eventhough I was pretty quickly able to make adjustments on my unit (well enough to pass cave ccr crossover), some of the tips and tricks I got from fundies made me slap my forehead and realize I was a dumbass for missing some minor things (which would have made the transition even faster).
So I get your point, but I really believe the transition to ccr can be very humbling to a diver of any skill level. It also depends on how you plan to dive your unit. I think a single al40 slung on my side would have made the transitiion a little easier, but that's not how I planned to dive long term. So starting with sidemounted bailout from the get go was the only way to go, but it also presents additional hurdles to properly balance the rig.
After a few dozen hours on the unit that buoyancy control does come back such that time at deco isn't the onerous chore it was when first moving to CCR. Even leave the SMB reel bouncing up and down in front and just hovering again.
The odd thing is I'm not sure what's different in terms of technique. I think it might be that a slight tweak to depth, e.g. have sunk down a foot/30cm is counteracted with a sort of dolphin fin kick, or even a kind of fin sculling movement. This gets back on to the target depth without dumping/adding gas. It must be working as diluent usage has halved or more.
Feels a little like when a back-finning manoeuvrer just works without thinking about it.
Jeremy Williams
Contributor
I think the thing that helped me mentally... and I don't recall who told me this or where I read it... but it's this...
On open circuit, your first instinct is to change YOUR buoyancy every time... breath in or out... add or dump air for your wing... etc...
On closed circuit, it helps a lot if you stop to think about whether you NEED to change your buoyancy if you COULD just swim to the point where your current buoyancy is ALREADY correct and neutral. Maybe you just swim down a bit to the point where the problem goes away? Or you could overcome a temporary change in buoyancy as you go over an obstacle with a couple of extra fin kicks instead. Just a thought.
On open circuit, your first instinct is to change YOUR buoyancy every time... breath in or out... add or dump air for your wing... etc...
On closed circuit, it helps a lot if you stop to think about whether you NEED to change your buoyancy if you COULD just swim to the point where your current buoyancy is ALREADY correct and neutral. Maybe you just swim down a bit to the point where the problem goes away? Or you could overcome a temporary change in buoyancy as you go over an obstacle with a couple of extra fin kicks instead. Just a thought.
Just slightly angled up.
broncobowsher
Contributor
Another one of those that questioned what the hell I just bought and if it was a bad mistake. I will admit my learning curve was a lot flatter than the others. Dialed in on the 3rd dive? Not a chance. A lot better on the 3rd, but not dialed in by a long shot. I racked up hours for the first year with my MOD1 and that was where I needed to be. Year two I finally got to use the rebreather like it should be after getting the Normoxic Trimix class.
I'm still not as dialed in as I was on OC. But I do enjoy the CC diving a lot more. Even with the added complexity, I find it a lot more comfortable.
I wonder how I would do on OC? I am sure my air consumption would be through the roof.
I'm still not as dialed in as I was on OC. But I do enjoy the CC diving a lot more. Even with the added complexity, I find it a lot more comfortable.
I wonder how I would do on OC? I am sure my air consumption would be through the roof.
The thread is about first open water dives on rebreather. I aint whining about it, aint complaining it's "so hard" neither, just building some common ground with the OP and attempting to be encouraging.
******* up occasionally is a good thing, it teaches humility. You should try it sometime.
- Messages
- 414
- Reaction score
- 502
- # of dives
- I'm a Fish!
You guys actually dive these death boxes?
Similar threads
