Who has had to bailout?

[RedSeaDiver2]

To which one has to ask why? As in why would you buy a Closed-Circuit machine that's been deliberately restricted and requires money to make into a working machine?

There definitely are good reasons for a SCR, diving in places without high pressure oxygen for example.

Galvanic cells have always been one of the biggest weakpoints of a rebreather, and so the constant cell validity system that the Poseidon uses appealed to me, back when they were first introduced and there weren't any on the secondhand marketyou couldn't buy the tech versions without having the appropriate certs so I had to buy the recreational version and progress upwards from there.

 

[Wibble]

Are the cells OK?

Can't you buy a "black" battery? Is it rechargeable?

(Rarely see Poseidon rebreathers around here)

 

[RedSeaDiver2]

Are the cells OK?

Can't you buy a "black" battery? Is it rechargeable?

(Rarely see Poseidon rebreathers around here)

Can buy a black battery easily these days, but when the rebreathers were first launched the batteries were very carefully controlled.
The nice thing now with the Poseidon's is the solid state cells - they are great!

 

[sprockjohnson]

Bailed out once on my Sport KISS. Although it passed negative and positive pressure tests the original BOV one way valves had come to the end of their useful and reliable lifespan and weren't sealing completely on either inhales or exhales. I should have caught this in a pre-dive checklist but failed to pinch hoses to check due to being in a hurry to catch up with my OC buddies who were already in the water and waiting on me. Shame on me. I could tell something was wrong even after doing an o2 flush at about 15 feet and ended up bailing out.

Due to the unavailability of the original valves (some type of plastic coated fabric which is held in place by a screw on the spider) I ended up just changing over to a DSV with more common mushroom valves. No problems since then and am now religious about doing the checklist.

 

[mdwalter]

Only time I have HAD to bailout to OC for real (i.e. not for training purposes, etc.) was a few years ago when I was demo diving a Liberty SM unit. The owner of the unit who was giving me the demo, and with me on the dive, had apparently already run 1 too many demos that day without having refilled the tiny onboard O2 supply. I'd say this was his fault, but let's just say it was my fault for trusting him and not checking myself before the dive. So what happened was we did a 20 or 30 minute dive to 40 or 50 feet depth, and as we ascended the PPO2 kept dropping even as I kept hitting the O2 MAV. When the PPO2 hit 0.17 and I still had not figured out what the problem was, I bailed out to OC. Since at this point we were at 10 feet, I could have just done a CESA at that point. If I had realized what the real issue was, I could have just done a dil flush to bring it back up to 0.21 or more, but since I was in doubt, I bailed out.

Update: I did a "non-training" bailout in August, but was expecting to have to bail out at some point in that dive because I was purposely pushing the scrubber life of my unit (on a "shallow" OW dive from which I could easily surface at any point) to see what it actually could be. I started the dive with a EAC that already had amost 7 hours on it, and was paying close attention to my breathing rate and how my head felt to monitor myself for signs of hypercapnia. About 45 minutes in, I felt it starting to set in, so I bailed out (as planned?) and finished the dive on OC. I went back on the loop for a minute or two right before surfacing just to see if I could still feel the level of CO2 too high, and yes, the scrubber was really done. I say this was a "non-training" dive because I was not doing this at the direction of an instructor, but I guess one could argue that I was training myself to recognize a failed scrubber so maybe this was a training dive. The bailout was definitely planned and I did warn my buddies ahead of time that they would likely see me bail out at some point on this dive (and don't freak out), but I just didn't know at what point in the dive it would become necessary.