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Last Dive at The Pit – Bailing Out at Depth

If you have been following Quiet Diver, you know that I left Mexico a couple of days ago.  And while I was in transit, I was torturing you with stories that were unrelated to diving.  Well, this story gets us back to writing about diving!

A month or so ago Santiago and I made a dive at The Pit down the Lins/Walten tunnel.  It was a nice dive to 238ft (73m).   Santiago was diving OC and I was on the Megalodon.   After the dive we had some helium left over and we enjoyed diving together so much we decided it would be cool to do a dive to the back of Wakulla Room as a team.  Additionally,  we needed to pick up some tanks that were staged from the last project and I still needed to do my at depth bailout.   So, we got another tank of helium and decided to do the dive in a couple of days.  Well, as the date approached I was too overwhelmed with work and had to call the dive.  These dives require a lot of preparation and mental focus and if my mind is on other issues, then I can’t do the dive.

Well, it took me more then a month to reschedule the dive between work and social engagements.  But once we got the dive scheduled everything fell into place.  All the gases were blended, regulators prepared and dive plans cut.

The plan was to stage gas at 20ft (6m) and 70ft (21m) on a down line.  Then set the primary reel and stage gas at 150ft.  For bottom gas Santiago took double 80’s and a deep stage.  I took two 80’s of deep bailout and the CCR.  Normally, I would carry one deep bailout for this dive, however since I was going to purposefully bail out, I thought it would be wise to carry extra gas.  As well, I was diving with an OC buddy and I wanted to be able to donate gas in the event of a lost gas situation.  After staging all the gas, we planned to swim to Paul’s Rock, which takes about 16 minutes.  Paul’s rock is about 800-900 (274 – 278) linear feet (meters) from the surface at a depth of 280ft (86m).  Upon reaching Paul’s Rock, I would signal Santiago that I was bailing out.  We would spend one minute sorting out the situation and then make for the exit with haste.  After exiting the Bypass, I planned to switch back onto the loop to conserve gas and do a normal CCR decompression schedule.

I had a several reasons for bailing out at depth:

  1. Switch from a rich HE mix to a lighter mix and experience a change in END and confirm our choice of deep bailout.
  2. Go through all the steps of bailing out under the effects of depth.
  3. Confirm my SAC rate in that configuration and under the environment stresses.
  4. Practice bailing out under the supervision of a trusted dive buddy at depth and get critical feedback.
  5. Complete the drill because I made Patrick complete the drill and he was riding me about it.
  6. Feel the tanks as they get really light with HE in them.
  7. Breath open circuit gas at depth while hustling.  (I never dove Trimix OC.)
  8. Practice, practice, practice!

The dive went nearly as planned.  We reached our way point at 150ft (46m) a little late, through a little effort we were able to make up the time and we reached Paul’s Rock on time.  I turned to Santiago and gave him an okay.  He replied.  I then gave him the bailout signal.  I reached up and turned the knob on my BOV.  I breathed out a little to clear the regulator of water and took a breath.  As I completed the breath I was immediately hit with a case of nerves.  I felt a shot of anxiety and adrenaline wash over me.  It was totally unexpected because I had mentally rehearsed the drill a pile of times and had executed it in shallower water many times.  My brain went a little mushy.  I reached around and opened the bailout tank valve.  For reference, I have my bailout tank and diluent tank plumbed into a manifold, so I now had access to both.  I had switched from an END of 67ft (20m) to an END of 92ft (29m).  Plus I went from an “unlimited” gas supply to a very limited gas supply.

After opening the bailout tank, I pulled my regulator out to replace my BOV.  As I pulled the regulator to my face, I reached up and pulled the BOV out of my mouth and thought to myself, “Don’t flood your unit – close the BOV.”  I reached around and switched the knob, opening the loop!  Dur! I heard the bubbles and quickly stuck the loop in my mouth.  I switched the loop closed and cleared the regulator.  I thought to myself, “You idiot!  That is exactly what you needed to not do.”  I took the BOV out of my mouth put the regulator in my mouth.  Confirmed I was breathing the right gas and looked at my set point controller.  I needed to set the set point down to manual.  It took my four tries to get it right.  I kept setting it to 1.4 instead of manual.   Finally, I got it set and then switched my X1 over to bailout, which I achieved on the first try.  I opened the OPV and started to swim.  The whole switch over took about 1 minute.  However, it really felt like a life time.  We swam for 5 minutes exiting the Bypass.  I switched back to CCR and made all the appropriate adjustments.

As we ascended, I picked up the staged tank at 220ft (68m).  The tank had been there for almost two months.  It was covered in billowing clouds of bacteria.  All the hoses were slimy and I was very glad I didn’t have to breathe from it.

The rest of deco went smoothly and was without incident.  Santiago and I had very similar schedules and exited the water pain-free.

As I hovered in deco, I had a lot of time to reflect about the dive.  The first thing that came to mind was how glad I was that I took the time to do the drill!  I wish I had done the drill last fall, when we first agreed that we would do it.  There is no harm in practicing this stuff, except to your wallet!  There is only benefit and experience.  Because my Meg is so reliable, I do not often get the opportunity to bail in a stressful situation.

Bailing out at depth in the back of a cave is different then bailing out in the first 1000ft (309m) of Ginnie, any shallow cave in Mexico or on the Jodrey.  I had bailed out repeatedly in those environments and never felt the anxiety or lack of coordination that doing it in The Pit caused.  I was definitely noticeably more impaired at that depth, even with a 96ft (29m) END.  I was glad to learn that my SAC rate held even at depth with a shot of adrenaline and a hasty exit.  I was also glad that I was able to get all the required tasks completed.  After the dive, I checked my loop for water and there was very little.  The towels in the bottom of the can were just a little wet.  So the open look fiasco wasn’t too detrimental.  I was glad that I identified that problem quickly and resolved it.

Santiago was concerned with how long it took me to bailout.  As he was on OC and run time tables the whole dive, he really needed to stay on schedule.  He suggested that I might have been better off starting to swim earlier.  I don’t know that I agree.  I think it is critical, even if I waste 1 minute, to get everything set and then start to swim.  I can only do one thing at a time in a situation like that, especially if my lizard brain starts to emerge.  In past situations, I really fumbled things by trying to do more then one thing at a time.  I have learned I need to complete one task then move on.

In response to his remarks and my performance, I would like to go through the drill again at depth a couple of times and maybe a couple more times in mid-range water.  I think when I get back to Q. Roo, I will schedule another bailout before I start deep diving activities at The Pit.  I may have the opportunity to give it a try this summer here in NJ.

Santiago said I looked somewhat impaired as I tried to set the handset.  I agree with his observation, I was.  Either it was anxiety or being narced.  I think it was an insidious mixture of both.  I know that when I get scared or nervous, even in shallow water, my cognitive abilities diminish.  Mix that with some depth and you have a nice cocktail.

Lastly, he was unhappy with how long it took me to get back on the loop and the distance I swam off the line when I switched back to the loop.  Both are valid concerns.  I swam off the line to avoid getting entangled.  As the line exits the By-pass it splits in two and ends up above you and below you in ugly spots.  So, I swam away from it.  As for taking too long, he was right.  I had a lot of trouble stuffing the hose back on the tank and as I was about to pick up another tank I needed to sort the bailout first. I think I need to get looser hose retainers and practice with them a bit.  I have a similar problem when I am dealing with my OC stages.

I am very happy with the dive.  It didn’t go perfectly, but I learned a lot and we had a ton of fun.  I am grateful to for my friend’s observations.  When you are in the moment, you miss things sometimes and a neutral observer can add a lot of depth to the discussion.  Santiago is an excellent diver and I look forward to my next opportunity to spend time with him.  I am sad because that was my last dive at The Pit for a while!  I really enjoyed diving at The Pit, especially the deep dives.  The Pit is a spiritual place for me.  I see it as a cathedral of diving.  The spaces are so big and beyond normal scale that it inspires me.  Until next time, I will dream of diving at The Pit.  To be honest, I am going to miss all my friends: Patrick, Solomon, Alain, Steve, Etienne, Ross, Katie and Santiago just to name a few.  The last year and a half of diving has been amazing and I have many fond memories.  Thanks to all of you, my life is forever enriched!

8 comments

1 Paul { 05.07.09 at 1:37 pm }

Welcome home. Hope to do some wreck diving with you soon.

2 Howard Packer { 05.07.09 at 11:11 pm }

Great story. Thanks for sharing. Should you ever really “need” to bail out in such a situation, you will have the confidence to be ready. That’s what it’s all about (even if it isn’t always pretty).

3 Ken Winter { 05.08.09 at 8:03 am }

Great write-up Hans. Welcome back to NJ. Drop me a line and we can go out on my buddy’s dive boat some time. I’m heading to Florida in 3 weeks for CCR cave and CCR trimix training.

I have one question about your mixes. You didn’t say what you used, but doesn’t picking a lighter mix for bottom bailout put you at risk for ICD? Not to mention the narcosis causing a significant pucker factor.

Ken

4 Patrick { 05.08.09 at 9:40 pm }

Sorry for beig late on that one but have a lot of work and didnt get to finish your story in the past days…

Great write up…you are cruely honest which I appreciate a lot since this sport is full of people that never make mistakes so it is a nice change to meet one who does…for the longest time I thought I am the only one…

Miss you too,
P

5 Cliff Pearson { 05.26.09 at 8:07 pm }

Having “bailed for real” in a cave, I can certainly agree that you are right. It is not like drills. I was amazed at how much gas I used in that short period of time, and I also found that my body reacted to the change in gas more dramatically than I would have expected.

Great writeup! Thanks for sharing.

6 Hans { 05.26.09 at 9:07 pm }

Cliff thank you for commenting. Bailing out and diving OC should be a regular part of CCR diver’s practice routine. The longer I spend on just CCR, the worse my OC performance becomes. It is really stunning and could conceivably leave you short on gas. I know I am going to stay current on my OC skills and continue to regularly bailout to stay practiced.

Hans

7 Bobby { 05.27.09 at 9:33 am }

Hans,
Good write up that shows the importance of practice, practice, practice. My deep set up is a bit different as I don’t utilize a BOV. I run my bottom mix side mount with diluent on my right side and bailout on my left. Both cylinders retain my standard side mount set up with LP QD hoses added for plug in to the RB. The left cylinder has the regulator on a necklace. When bailing out there is no need to deploy a regulator, just close the DSV and stick the reg in your mouth the same as switching regs on side mount. The long hose reg is stowed on the right cylinder in case a team member needs gas or I can’t go back on the loop and need access to both cylinders to exit.

For longer deep dives I use LP 108’s. I have two O2 cylinders on the breather for redundancy and use the 108’s as bail out and diluent. This also keeps the ends the same for OC & CCR. Just a few thoughts. I have a pictures in the rig set up for deep mix dives with two AL80’s for OC deco bail out and the two 108’s for bottom mix. Let me know if you would like to see them.

Keep the writing and diving up!!!

Bobby

8 Barbara/San Francisco { 11.30.11 at 10:47 am }

Wonderful. Thanks for telling us about it.