121 m on a Pelagian DCCCR

Rebreatherlab · 28th June 2007, 19:13

Hi there,

I just returned home from a little mini work holiday to the infamous Sra Keow Cave in Krabi. If anyone doubts it exist - it does! What I set out to do was to test the new Pelagian BOV. Not to brake any depth records. As I had never been there before I had no way of knowing how long it would take to reach my target depth, so I started with a late afternoon warm up, (read finding the lines), dive. As I like to travel light and had no support etc. I thought I could afford about an hour of fumbling around with out taking too much toll on the gas supply for the next days dive.

I started in the middle of one of the two adjacent pools that leads to the cave. I just picked the one with the least amount of elephant poo in!

The visibility was about minus 1m and the only readable gauge was the back lit Po2 handset. Usually visibility improves with depth, ( or at least this is what I encouraged myself thinking), so I carried on doing arm sweeps in hope to catch a line. After about ten minutes at 10 m I eventually found a sea weed infested old looking line and followed it for some time before I started thinking it must be some ones idea of a joke to discourage snoopy, non-initiated divers having a crack at the title! The line vent left right up and down only to come up again. Eventually I made it to 38 m where the vis got much better and the line seemed to have made up its mind to actually go down wards. All this mucking about took 35 minutes!
That's when I turned back up with the conclusion it would require quite a few waypoints to plan tomorrows dive. I surfaced conveniently right next to the edge of the pool making a mental note of the shape of the nearest tree.

Back at the ranch I simply downloaded the profile to my lap top and started manually inputting the superslow descent down to 40m in my Decocheq planner, and then assuming (hoping), the rest of the way to 120 m would be less up-and-down'ish.

The next day I thought if I just swim faster with an arm raised to take any rock collissions, (I dont have a funny cave hat yet), I should be able to get to 40 in at least 20 minutes. Following the line I ascended on the previous day provided to be a winner as it was apparently not the same as my original descend mess of a line. It took only 6 -7 minutes to reach 80 m.

Once the top layer of elephant bathing water is passed the cave really opens up and the vis becomes excellent. Quite enjoyable actually. I had packed twin aluminimum 19 cu. ft's for 13/53 and O2 and had two side slung alu 80's. One for 13/53 and one for 20/50. I had also planned to bring a 60 cu.ft of O2 to clip off somewhere, but left it since I was sure I wouldn't find it anyhow. The bail out plan was made making sure I could do the required deco with what I had anyway.

The relatively high o2 in the dil and bail gas was chosen as it was a short dive and I usually turn off the needle on the way down to metabolise some o2 out of the mix. Metabolism doesnt take much out at the deeper part, but the counterlungs dont compress much at the same depth range. Anyway I managed to keep the Po2 between 1.2 - 1.25 on the descent and had about 1.4 at 120m. A real bail to OC would have meant a Po2 of 1.6 BAR, but only until going up. If the cave passage had demanded a further descent to get out, I would have stopped at 100m. Anyway the passage seemed ideal as it provided a steady downward slope more or less straight from 80m.

Time to test the BOV:
I switched to the BOV which was feeding from the on board dil with the "real" off board tankvalve on and reg ready in the event of total disaster.
I took a few rapid and deep breahts and found it was super easy to breathe. The balance chamber adjustment knob was in its anti free flow position, or all the way clock wise. Still nice and happy breathing. I then went to the off board which was fed from a Scubapro MK16 (balanced membrane 1st with out silly antifreeze cap) and a Scubapro G250 balanced second stage with its venturi wing in the pre dive position. No noticeable difference. But honestly, there SHOULD be a difference since the G250 uses a larger membrane. Well I couldnt feel it. So that was it, time to go home.

The ascend was drama free apart from one cell that decided to die, (only 2 weeks old). The Pelagians build in instant cell validation came in handy as it took only a half breath diluant to find which one had packed up.

The Pelagian unit was not modified, (no oil in hand sets or battery chamber), and had the standard 3.4 kg scrubber. The Explorer scrubber would propably have been nice to have on dives sub 100 m, but anyway not the tiniest signs of hypercapnia. Decocheck predicted a total run time of 1 hr and 40 minutes, but I spent a total 2.5 hrs sight seing in between 80m to the surface putting my life in the hands of my VR3.

The real surprise was that I found my self in the surface of the other pool!
Apparently I have now done some fancy deep cave crossing, (not knowlingly), Anyway next time I will start from the pool I came up in as I had much more interesting marine life, ( shrimps and small fish ) and less elephant droppings.

Proof? Sorry no proof. I brought the camera on the 38 m dive and decided it would be too much to bring on the real dive, plus an extra snag point or something to loose. I have lost two cameras this year already. If anyone would like to see pictures of the VR3 log, the HS Explorer log or a picture of a dive watch reading --- give me a call!

The ones who know me knows I would never cook up a something like this. The ones who dont know me, just regard this as a fictioned spoof story and have a laugh!

Cheers,

Andy

***schford*** · 28th June 2007, 19:31

Thanks for the Report Andy :-) Excellent!

I know we swapped PMs and I have not got back to you but I look forward to getting an indepth report of the unit sorted for Rebreather World.

Stuart

gbmay · 29th June 2007, 02:10

Great report Andy. I can't wait to try out the Pelagian next August when you conduct our training program in the Philippines. We have plenty of deep water, down to over 500M, not that I want to go there, but just in case http://www.rebreatherworld.com/image...es/redface.gif

Keep the reports coming...

Drmike · 29th June 2007, 03:17

The 'shitty pool' has a spidersweb of lines running all over it. It was originally used as a training pool (lost line, entanglements etc. I keep meaning to clear it all out, ill get around to it someday) There is a line from the root of the biggest tree facing the other pool thats the right one - follow that take no diversions. IIRC it took me 25mins to get down to the traverse there - fun

if you like elephant poo.

Good info on the BOV.

Now what kinda guy would find themselves in a new cave on ascent

Im going to tell AM!!

Be over there again shortly (possibly tomorrow check out some shinny new gear) Next time im in town we should hook up even if its just for a beer.

Cheers
m

silent running · 29th June 2007, 03:48

Thanks for the report Andy, glad to hear that the BOV worked well at depth. I noticed that there's 3 holes in the bottom of the BOV housing. Obviously the bigger, center hole is for the diaphram/purge. But what are the other 2 for?

Rebreatherlab · 29th June 2007, 04:07

Not that it matters much but after (carefully), examining the down load it actually took 12 min. to reach 82 m and 17 minutes to reach 121 m.

I also noticed a quite deep, "deep stop" at 85 ish. That was when I lost my wedding ring. I thought I'd better not return home with out it as my wife would not buy any "Oh, lost it in a cave", but rather be sure I'd lost it in a bar!

The entanglement simulation line explains a lot! I belive the "right" line was the one I took on the second day.

I used to work in the Phillipines around 96 - 97. Fantastic place. You could do "pool" training on top of the house reef and then after a 50 m swim you would have a virtual abyss going down to 400 or so.

Many crazy deep air dives performed like some kind of free dives taught me about the effects of Co2 build up, deep water black out and other goodies!

Mike: Yes beers, popcorn and gear petting. Anytime!

Andy

Drmike · 29th June 2007, 04:12

Quote: (Originally Posted by Rebreatherlab)

Not that it matters much but after (carefully), examining the down load it actually took 12 min. to reach 82 m and 17 minutes to reach 121 m.

Aha!!! The curse of Sra Keow strikes again

Rebreatherlab · 29th June 2007, 04:14

Hi Andy,

As the BOV is machined as tight as possible there is only about 0.5 mm clearance between the purge lid and diaphragm. The extra two holes aids the water suction on the inhalation. Nothing more spectacular Im afraid!

Cheers,

Andy

Quote: (Originally Posted by silent running)

Thanks for the report Andy, glad to hear that the BOV worked well at depth. I noticed that there's 3 holes in the bottom of the BOV housing. Obviously the bigger, center hole is for the diaphram/purge. But what are the other 2 for?

Rebreatherlab · 29th June 2007, 04:16

Quote: (Originally Posted by Drmike)

Aha!!! The curse of Sra Keow strikes again

Hrm. After carefully examining the profile it seems the max depth was only 12.1 m. No that was a bad joke!

Andy

silent running · 29th June 2007, 05:56

Quote: (Originally Posted by Rebreatherlab)

Hi Andy,

As the BOV is machined as tight as possible there is only about 0.5 mm clearance between the purge lid and diaphragm. The extra two holes aids the water suction on the inhalation. Nothing more spectacular Im afraid!

Cheers,

Andy

Well Andy, you are one thorough fellow. Thanks for the explanation, makes sense.

28th June 2007, 19:13	#1 (permalink)
Rebreatherlab RebreatherWorld Sponsor Current Rebreather/s: Pelagian Other Rebreather/s: Not Bought Yet Classic Kiss Pelagian Join Date: Sep 2005 Location: Thailand Posts: 199	121 m on a Pelagian DCCCR Hi there, I just returned home from a little mini work holiday to the infamous Sra Keow Cave in Krabi. If anyone doubts it exist - it does! What I set out to do was to test the new Pelagian BOV. Not to brake any depth records. As I had never been there before I had no way of knowing how long it would take to reach my target depth, so I started with a late afternoon warm up, (read finding the lines), dive. As I like to travel light and had no support etc. I thought I could afford about an hour of fumbling around with out taking too much toll on the gas supply for the next days dive. I started in the middle of one of the two adjacent pools that leads to the cave. I just picked the one with the least amount of elephant poo in! The visibility was about minus 1m and the only readable gauge was the back lit Po2 handset. Usually visibility improves with depth, ( or at least this is what I encouraged myself thinking), so I carried on doing arm sweeps in hope to catch a line. After about ten minutes at 10 m I eventually found a sea weed infested old looking line and followed it for some time before I started thinking it must be some ones idea of a joke to discourage snoopy, non-initiated divers having a crack at the title! The line vent left right up and down only to come up again. Eventually I made it to 38 m where the vis got much better and the line seemed to have made up its mind to actually go down wards. All this mucking about took 35 minutes! That's when I turned back up with the conclusion it would require quite a few waypoints to plan tomorrows dive. I surfaced conveniently right next to the edge of the pool making a mental note of the shape of the nearest tree. Back at the ranch I simply downloaded the profile to my lap top and started manually inputting the superslow descent down to 40m in my Decocheq planner, and then assuming (hoping), the rest of the way to 120 m would be less up-and-down'ish. The next day I thought if I just swim faster with an arm raised to take any rock collissions, (I dont have a funny cave hat yet), I should be able to get to 40 in at least 20 minutes. Following the line I ascended on the previous day provided to be a winner as it was apparently not the same as my original descend mess of a line. It took only 6 -7 minutes to reach 80 m. Once the top layer of elephant bathing water is passed the cave really opens up and the vis becomes excellent. Quite enjoyable actually. I had packed twin aluminimum 19 cu. ft's for 13/53 and O2 and had two side slung alu 80's. One for 13/53 and one for 20/50. I had also planned to bring a 60 cu.ft of O2 to clip off somewhere, but left it since I was sure I wouldn't find it anyhow. The bail out plan was made making sure I could do the required deco with what I had anyway. The relatively high o2 in the dil and bail gas was chosen as it was a short dive and I usually turn off the needle on the way down to metabolise some o2 out of the mix. Metabolism doesnt take much out at the deeper part, but the counterlungs dont compress much at the same depth range. Anyway I managed to keep the Po2 between 1.2 - 1.25 on the descent and had about 1.4 at 120m. A real bail to OC would have meant a Po2 of 1.6 BAR, but only until going up. If the cave passage had demanded a further descent to get out, I would have stopped at 100m. Anyway the passage seemed ideal as it provided a steady downward slope more or less straight from 80m. Time to test the BOV: I switched to the BOV which was feeding from the on board dil with the "real" off board tankvalve on and reg ready in the event of total disaster. I took a few rapid and deep breahts and found it was super easy to breathe. The balance chamber adjustment knob was in its anti free flow position, or all the way clock wise. Still nice and happy breathing. I then went to the off board which was fed from a Scubapro MK16 (balanced membrane 1st with out silly antifreeze cap) and a Scubapro G250 balanced second stage with its venturi wing in the pre dive position. No noticeable difference. But honestly, there SHOULD be a difference since the G250 uses a larger membrane. Well I couldnt feel it. So that was it, time to go home. The ascend was drama free apart from one cell that decided to die, (only 2 weeks old). The Pelagians build in instant cell validation came in handy as it took only a half breath diluant to find which one had packed up. The Pelagian unit was not modified, (no oil in hand sets or battery chamber), and had the standard 3.4 kg scrubber. The Explorer scrubber would propably have been nice to have on dives sub 100 m, but anyway not the tiniest signs of hypercapnia. Decocheck predicted a total run time of 1 hr and 40 minutes, but I spent a total 2.5 hrs sight seing in between 80m to the surface putting my life in the hands of my VR3. The real surprise was that I found my self in the surface of the other pool! Apparently I have now done some fancy deep cave crossing, (not knowlingly), Anyway next time I will start from the pool I came up in as I had much more interesting marine life, ( shrimps and small fish ) and less elephant droppings. Proof? Sorry no proof. I brought the camera on the 38 m dive and decided it would be too much to bring on the real dive, plus an extra snag point or something to loose. I have lost two cameras this year already. If anyone would like to see pictures of the VR3 log, the HS Explorer log or a picture of a dive watch reading --- give me a call! The ones who know me knows I would never cook up a something like this. The ones who dont know me, just regard this as a fictioned spoof story and have a laugh! Cheers, Andy __________________ www.rebreatherlab.com
(Online)

28th June 2007, 19:31	#2 (permalink)
*schford* Despotic Overlord Current Rebreather/s: Megalodon Sport Kiss Other Rebreather/s: Join Date: Jan 2005 Location: London, UK Posts: 3,673	Re: 121 m on a Pelagian DCCCR Thanks for the Report Andy :-) Excellent! I know we swapped PMs and I have not got back to you but I look forward to getting an indepth report of the unit sorted for Rebreather World. Stuart __________________ Bailout and Kit Management account for Murphy's Law The only bad question is one you did not ask and later wish you had. Use of Rebreather World is subject to the Rebreather World Terms & Conditions of Use
(Offline)

29th June 2007, 02:10	#3 (permalink)
gbmay New Member Current Rebreather/s: Inspiration Classic Pelagian Dolphin Azimuth Other Rebreather/s: Pelagian Dolphin Azimuth Join Date: Jun 2005 Location: Philippines Posts: 18	Re: 121 m on a Pelagian DCCCR Great report Andy. I can't wait to try out the Pelagian next August when you conduct our training program in the Philippines. We have plenty of deep water, down to over 500M, not that I want to go there, but just in case http://www.rebreatherworld.com/image...es/redface.gif Keep the reports coming...
(Offline)

29th June 2007, 03:17	#4 (permalink)
Drmike Custom Title Allowed! Current Rebreather/s: MK 15.X Ouroboros Other CCR Home Build Other Rebreather/s: Inspiration Classic Other CCR Home Build Join Date: Feb 2005 Posts: 3,163	Re: 121 m on a Pelagian DCCCR The 'shitty pool' has a spidersweb of lines running all over it. It was originally used as a training pool (lost line, entanglements etc. I keep meaning to clear it all out, ill get around to it someday) There is a line from the root of the biggest tree facing the other pool thats the right one - follow that take no diversions. IIRC it took me 25mins to get down to the traverse there - fun if you like elephant poo. Good info on the BOV. Now what kinda guy would find themselves in a new cave on ascent Im going to tell AM!! Be over there again shortly (possibly tomorrow check out some shinny new gear) Next time im in town we should hook up even if its just for a beer. Cheers m __________________ Cave diving is a sport Wreck diving is a sport Diving in general is a sport 'Rebreather diving' is not a sport its the delusional obsession with a highly dangerous and often inappropriate piece of equipment
(Offline)

29th June 2007, 03:48	#5 (permalink)
silent running Mature mouth breather Current Rebreather/s: Prism Topaz Other Rebreather/s: Join Date: Jun 2005 Location: U.S.A. Brooklyn, New York Posts: 1,814	Re: 121 m on a Pelagian DCCCR Thanks for the report Andy, glad to hear that the BOV worked well at depth. I noticed that there's 3 holes in the bottom of the BOV housing. Obviously the bigger, center hole is for the diaphram/purge. But what are the other 2 for?
(Offline)

29th June 2007, 04:07	#6 (permalink)
Rebreatherlab RebreatherWorld Sponsor Current Rebreather/s: Pelagian Other Rebreather/s: Not Bought Yet Classic Kiss Pelagian Join Date: Sep 2005 Location: Thailand Posts: 199	Re: 121 m on a Pelagian DCCCR Not that it matters much but after (carefully), examining the down load it actually took 12 min. to reach 82 m and 17 minutes to reach 121 m. I also noticed a quite deep, "deep stop" at 85 ish. That was when I lost my wedding ring. I thought I'd better not return home with out it as my wife would not buy any "Oh, lost it in a cave", but rather be sure I'd lost it in a bar! The entanglement simulation line explains a lot! I belive the "right" line was the one I took on the second day. I used to work in the Phillipines around 96 - 97. Fantastic place. You could do "pool" training on top of the house reef and then after a 50 m swim you would have a virtual abyss going down to 400 or so. Many crazy deep air dives performed like some kind of free dives taught me about the effects of Co2 build up, deep water black out and other goodies! Mike: Yes beers, popcorn and gear petting. Anytime! Andy __________________ www.rebreatherlab.com
(Online)

29th June 2007, 04:12	#7 (permalink)
Drmike Custom Title Allowed! Current Rebreather/s: MK 15.X Ouroboros Other CCR Home Build Other Rebreather/s: Inspiration Classic Other CCR Home Build Join Date: Feb 2005 Posts: 3,163	Re: 121 m on a Pelagian DCCCR Quote: (Originally Posted by Rebreatherlab) Not that it matters much but after (carefully), examining the down load it actually took 12 min. to reach 82 m and 17 minutes to reach 121 m. Aha!!! The curse of Sra Keow strikes again __________________ Cave diving is a sport Wreck diving is a sport Diving in general is a sport 'Rebreather diving' is not a sport its the delusional obsession with a highly dangerous and often inappropriate piece of equipment
(Offline)

29th June 2007, 04:14	#8 (permalink)
Rebreatherlab RebreatherWorld Sponsor Current Rebreather/s: Pelagian Other Rebreather/s: Not Bought Yet Classic Kiss Pelagian Join Date: Sep 2005 Location: Thailand Posts: 199	Re: 121 m on a Pelagian DCCCR Hi Andy, As the BOV is machined as tight as possible there is only about 0.5 mm clearance between the purge lid and diaphragm. The extra two holes aids the water suction on the inhalation. Nothing more spectacular Im afraid! Cheers, Andy Quote: (Originally Posted by silent running) Thanks for the report Andy, glad to hear that the BOV worked well at depth. I noticed that there's 3 holes in the bottom of the BOV housing. Obviously the bigger, center hole is for the diaphram/purge. But what are the other 2 for? __________________ www.rebreatherlab.com
(Online)

29th June 2007, 04:16	#9 (permalink)
Rebreatherlab RebreatherWorld Sponsor Current Rebreather/s: Pelagian Other Rebreather/s: Not Bought Yet Classic Kiss Pelagian Join Date: Sep 2005 Location: Thailand Posts: 199	Re: 121 m on a Pelagian DCCCR Quote: (Originally Posted by Drmike) Aha!!! The curse of Sra Keow strikes again Hrm. After carefully examining the profile it seems the max depth was only 12.1 m. No that was a bad joke! Andy __________________ www.rebreatherlab.com
(Online)

29th June 2007, 05:56	#10 (permalink)
silent running Mature mouth breather Current Rebreather/s: Prism Topaz Other Rebreather/s: Join Date: Jun 2005 Location: U.S.A. Brooklyn, New York Posts: 1,814	Re: 121 m on a Pelagian DCCCR Quote: (Originally Posted by Rebreatherlab) Hi Andy, As the BOV is machined as tight as possible there is only about 0.5 mm clearance between the purge lid and diaphragm. The extra two holes aids the water suction on the inhalation. Nothing more spectacular Im afraid! Cheers, Andy Well Andy, you are one thorough fellow. Thanks for the explanation, makes sense.
(Offline)

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