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**Mark Chase** · 6th December 2008, 15:17

I have been asked to move this here as a new discussion rather than change the course of the Shearwater v VRX thread.

Basicly this is an example of a typical bailout problem id face on a 45min dive to 70m. The discusion was concerning the need as deep CCR divers for a get shallow fast bailout deco profile on our dive computers.

Id be most interested to hear how other CCR divers plan in the 60m+ range.

__________________________________________________ ______

Lets look at a practical example of what I am trying to achieve.

If we look at a bailout from a 1.3set point on the bottom at 70m after 45mins on GF 10/90

Bail out gas is 18/45 50% and 100%

I bailout at 70m on to 18/45 and my first stop depth (10/90GF) is showing as 48m and my Time to surface is 133mins.

I am breathing like a sexually aroused hippo so I am in trouble and i switch to my emergency bailout deco plan of 100/100GF

My first stop depth is now 30m and my deco time is 98mins

The first point to note here is I had no idea of haw far i could push it on my first stop. If my computer said 48m and i had no other bailout deco plan, Id have to guess how far above 48m my minumum depth ceiling was. Looking at a 100/100GF profile I would then have a tangible figure in my head as to the minimum depth I can ascend to at 8m-10m/min

In a comparison between the two profiles I have saved eight mins on my ascent to the first stop depth.

Running 10/90GF on a 30sac id need 1533.00 ltrs of gas to make it to 30m and a further 1749ltrs to make it to the 21m gas switch.

Total 3282.00ltrs or 329bar in a 10ltr tank

I am not going to make it I am 932ltrs or to put it another way 10mins short of gas.

So I know I am breathing like a train and wont be able to match mu planned 20SAC plan so I go for bend and mend and switch to 100/100GF bailout.

4mins to 30m = 660ltrs of gas required. Running 100/100 GF it will take me a further 8mins to get to the 21m gas switch costing me a further 843ltrs of gas.

So on my emergency plan I need 1503ltrs of gas and i have 2350ltrs available

Knowing I have a healthy reserve despite my SAC I could slow down the ascent and probably stop at 33 and 36m to soften the blow of 100/100 on trimix.

Id also be aware of the fact i was softening the deco which would boost my confidence and help reduce my SAC further.

By the 21m stop and switch to 50% I would have got through my 2350 ltrs of deep bailout on OC and I hope id be breathing in a much more noraml way so i can manualy pad out the stops between 21m and the surface to compensate for the high gf OR if the new software for the X1 does what i hope, I can folow the less agressive profile also displayed on the screen.

Seeing this information on my screen and knowing I can manipulate the dive from now on to soften the effects of my earlier indiscretions I will have my confidence boosted which will help to calm me down and in doing so further reduce my SAC again. Having it show missed stops / violated ceilings and just a TTS figure based on nothing I can get my head around is going to do the opposite.

I don't have a clue how to do this on VPlanner which is why i have shied away from it in the past.

I looked at this dive running VPMBE 3 and VPMB 0 and it still gave me loads of gas munching deep stops. On VPMBE it gives a first proper stop at 54m and on VPMB 0 its 48m??

Running VPMBe 3 on a 30 SAC id use 4107ltrs of gas

Running my bailout plan of VPMB 0 Id need 3431ltrs

Its simply not possible to run VPM on this dive an carry only 2350ltrs of 18/45 in a 10ltr for bailout, even on my emergency plan.

If any one has any commnets on what they do or how to do this dive using VPM id be very interested to here them.

ATB

Mark

6th December 2008, 15:17	#1 (permalink)
Mark Chase So many CCR So little etc JJ Hybrid Inspo, Hammer Head, KISS rEvo Join Date: Jan 2005 Location: Kent Posts: 4,304	Deep bailout with high SAC VPM & GF deco I have been asked to move this here as a new discussion rather than change the course of the Shearwater v VRX thread. Basicly this is an example of a typical bailout problem id face on a 45min dive to 70m. The discusion was concerning the need as deep CCR divers for a get shallow fast bailout deco profile on our dive computers. Id be most interested to hear how other CCR divers plan in the 60m+ range. __________________________________________________ ______ Lets look at a practical example of what I am trying to achieve. If we look at a bailout from a 1.3set point on the bottom at 70m after 45mins on GF 10/90 Bail out gas is 18/45 50% and 100% I bailout at 70m on to 18/45 and my first stop depth (10/90GF) is showing as 48m and my Time to surface is 133mins. I am breathing like a sexually aroused hippo so I am in trouble and i switch to my emergency bailout deco plan of 100/100GF My first stop depth is now 30m and my deco time is 98mins The first point to note here is I had no idea of haw far i could push it on my first stop. If my computer said 48m and i had no other bailout deco plan, Id have to guess how far above 48m my minumum depth ceiling was. Looking at a 100/100GF profile I would then have a tangible figure in my head as to the minimum depth I can ascend to at 8m-10m/min In a comparison between the two profiles I have saved eight mins on my ascent to the first stop depth. Running 10/90GF on a 30sac id need 1533.00 ltrs of gas to make it to 30m and a further 1749ltrs to make it to the 21m gas switch. Total 3282.00ltrs or 329bar in a 10ltr tank I am not going to make it I am 932ltrs or to put it another way 10mins short of gas. So I know I am breathing like a train and wont be able to match mu planned 20SAC plan so I go for bend and mend and switch to 100/100GF bailout. 4mins to 30m = 660ltrs of gas required. Running 100/100 GF it will take me a further 8mins to get to the 21m gas switch costing me a further 843ltrs of gas. So on my emergency plan I need 1503ltrs of gas and i have 2350ltrs available Knowing I have a healthy reserve despite my SAC I could slow down the ascent and probably stop at 33 and 36m to soften the blow of 100/100 on trimix. Id also be aware of the fact i was softening the deco which would boost my confidence and help reduce my SAC further. By the 21m stop and switch to 50% I would have got through my 2350 ltrs of deep bailout on OC and I hope id be breathing in a much more noraml way so i can manualy pad out the stops between 21m and the surface to compensate for the high gf OR if the new software for the X1 does what i hope, I can folow the less agressive profile also displayed on the screen. Seeing this information on my screen and knowing I can manipulate the dive from now on to soften the effects of my earlier indiscretions I will have my confidence boosted which will help to calm me down and in doing so further reduce my SAC again. Having it show missed stops / violated ceilings and just a TTS figure based on nothing I can get my head around is going to do the opposite. I don't have a clue how to do this on VPlanner which is why i have shied away from it in the past. I looked at this dive running VPMBE 3 and VPMB 0 and it still gave me loads of gas munching deep stops. On VPMBE it gives a first proper stop at 54m and on VPMB 0 its 48m?? Running VPMBe 3 on a 30 SAC id use 4107ltrs of gas Running my bailout plan of VPMB 0 Id need 3431ltrs Its simply not possible to run VPM on this dive an carry only 2350ltrs of 18/45 in a 10ltr for bailout, even on my emergency plan. If any one has any commnets on what they do or how to do this dive using VPM id be very interested to here them. ATB Mark __________________ See my "Doing It Chasey" video where I'm locked into a padded room, naked, with two ball bearings and within an Hour, I manage to lose one and break the other!!! Kevin Juergensen 16/11/08 [/QUOTE] Last edited by Mark Chase; 6th December 2008 at 15:22..
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