CCR Bailout Planning

[Steve_]

I've been doing a lot of diving in different kinds of cave lately and am interested in seeing how people adjust their bailout based on the cave. I'm curious to see how different CCR divers would plan bailout (what tanks, do you stage or not, why) for these three dives:

1. Swim to the Henkel

2. A tight Sidemount/silty passage thats guaranteed to be blown out on your way out. Say a total of 500 feet of passage at 100 foot depth.

3. An easy but long dive, where you plan on having lots of deco. Say 4 hours of bottom time checking out various jumps in the first 1800 feet of Ginnie, planning for 90 minutes of deco.

Also interested to hear any other situation that would require a different approach to bailout planning.

[Superlyte27]

I've been doing a lot of diving in different kinds of cave lately and am interested in seeing how people adjust their bailout based on the cave. I'm curious to see how different CCR divers would plan bailout (what tanks, do you stage or not, why) for these three dives:

1. Swim to the Henkel

2. A tight Sidemount/silty passage thats guaranteed to be blown out on your way out. Say a total of 500 feet of passage at 100 foot depth.

3. An easy but long dive, where you plan on having lots of deco. Say 4 hours of bottom time checking out various jumps in the first 1800 feet of Ginnie, planning for 90 minutes of deco.

Also interested to hear any other situation that would require a different approach to bailout planning.

I once asked a cave instructor how much gas he uses to swim to the Henkel. He told me he?s never swam to the Henkel just like he?s never walked to Gainesville from High Springs. I?ve never actually swam to the Henkel either. But... If I were to swim to the Henkel, I?d leave a bottle of O2 (40cu?) at 20? and I?d plan on 70 fpm at 1.0 sac rate. So, 3200? / 70fpm x 4 = 182.85cu?. Because LP85?s work great, and are 232cu? of gas at 3600psi, that would most likely be my bailout of choice. FYI, my swimming sac is about .4 or .5, so 1.0 would be nice and conservative. My deco sac rate is about .25. So an AL40 would last a LONG time.

Sidemount cave wouldn?t be much different. I?d up the conservatism and slow the exit speed. It once took me 30 minutes to get passed the restriction at Rocky Horror after I zeroed vis. Vis was less than 5? for another 20 minutes. One of the readers here was on that dive.....

If my dive to Ginnie has no more penetration than 1800?, I?d probably do that on jacked LP50?s and an AL40. LP50?s with 3600psi have 136cu? of gas. So 1800/70*4= 102cu?. 40cu? at 20? with a .25 sac rate should last me 90 minutes. Of course this is assuming that the rebreather died at max penetration and max plan dive time. If it dies before that, I?ve cut the dive short and my deco isn?t as long. If it?s longer than that, I?ve got some padding in the AL40 and some padding in the LP50?s.

You didn?t say whether I brought a buddy along. I don?t ever count on them for my gas needs, but there might be some extra gas from them.

[Superlyte27]

Obviously, if we’re doing something expeditiously like 6+ hours on a 300’ dive, we’ve staged a buttload of gas. But that’s not really “my buddy’s”, it’s all of our gas, should someone need it.

[Germie]

I can only answer from some experiences in Europe. I have dived Ginnie, but I don't know by head what the Henkel is. I have to look it up.

I did the eol in the Landenouse cave in France. That is 1241 m from entrance to a depth of 85m.
We took scooters, and dropped at 6m 2 ali80's with oxygen. Both (we were a 2 diver team) had a ali80 with 15/55, one 18/45 and one 21/35. The cave is a long time between 60 and 67m deep and then drops quite fast to 72 and then to 85 where the line ends in gravel (yes I know it is taken further now, but you have to dig you in and out of gravel). We also dropped 1 ali80 with ean50. So we scootered with 3 stages, dropped then the 21/35. But decided not to drop the other 2 gases. The official rule may be gas for 1.5 diver as bailout, but most times we have more gas. When deco is planned, we prefer to have more than enough oxygen. This is dropped in the beginning of the dive, so no problems to take it with you. Sometimes we hold it in hands and just drop it at the cave entrance. Or drop it and then come back to pick up other bailouts and start the dive.

When I do solo the first 1200-1300 m in the Saint Georges, swimming, I know from my oc diving that I need 1 ali80 to swim out the last 400m (at 400m there is a restriction, but can be done in backmount easy). This is normally less than 1/3 of a twin12, so for me a ali80 will work including reserve. I take this cylinder extra. It is officially not needed in the bailout plan, but if I have a problem I can decide to drop the other 3 ali80's, and then only pickup the 1 and swim out. With a twinset I can pickup the dropped cylinders later easy.
The cave goes to 29m directly after the entrance, and then goes shallower. After about 900m it is only 2m deep and then goes to 76m depth and stay at that depth for about 180m. Swimming I don't do the whole sump, most times I take a max of 15 minutes at that depth (so 7 minutes in). This means you have to take your decogasbailouts with you in the cave. I normally take 1 bottomgas, one ean50 and 1 oxygen. All ali80's (I don't own smaller cylinders for bailouts). And I take an ean32 to be dropped at 400m near the resctrion. When swimming it will take around 1 hour to reach the 76m depth. Almost half of the distance can be done with the ean50. The rest with the bottomgas. But the ean32 is just extra.

If deco is 90 minutes, for sure I have dropped an oxygen. If this does not fit at 6m, I will drop it where it will nobody hurt. Oxygen is most times the easiest bailout and decogas to take with you, in the first few minutes it is dropped.

[kensuf]

1. Hinkle, twin 85's. Anytime I am going beyond the hinkle I start dropping stage bottles.

2. Depends on the time we expect it'll take to move through that tight silty section. If it's going to take 40 minutes to negotiate I bring more than an hours worth of gas for that section.

3. Enough to get you out, cover your deco, and give you a little extra in case.

You know, there are instructors that teach this stuff and have experience doing this type of diving. I'm one of them. Let me know if I can help.

[rddvet]

Haven’t done any of these dives on car yet, but based on gas planning we did in my car course (focused on cave diving since that’s pretty much all we do), Ken and SuperLytes recommendations line up precisely with what I was taught.

Except for the sm one. We really didn’t discuss that. Though I’d be ultra conservative.

[OFG-1]

Haven?t done any of these dives on car yet, but based on gas planning we did in my car course (focused on cave diving since that?s pretty much all we do), Ken and SuperLytes recommendations line up precisely with what I was taught.

Except for the sm one. We really didn?t discuss that. Though I?d be ultra conservative.

Must be a really small car, like a Fiat or Mini.

[rddvet]

Must be a really small car, like a Fiat or Mini.

Damn autocorrect. Ccr

Thanks


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[Superlyte27]

What's with all the "?" in my post. It looks like I have some rare form of typed tourettes syndrome.

[Dsix36]

1 - I carry 2 al80 and stage one more. I insist on a minimym of 80cf per 1000'

2 - douuble it

3 - just my 2 carriwd tanks and stage the dwco gasses

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