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From: "Phi Le" <decoweenie@ya*.co*>
To: "George Morris" <george.morris@ci*.co*>,
     "'Adam Volosik'" ,
Cc: <techdiver@aquanaut.com>
Subject: RE: accident
Date: Wed, 4 Jul 2001 00:31:01 +0200
George,

Couple of points:

1. The set-point used was 1.2, not 1.3, due to one of the divers came from
altitude. So your numbers would be even higher...

2. You are mixing your ascent rates which makes a big difference.

3. On bail-out of this type, the objective is to get out of the water ASAP
without seriously hurting yourself. With only 1 x 80cf of bottom gas, I, for
one, wouldn't be doing 2-minute Pyle stops on the way up. I would have used
a straight Buhlmann bail-out plan with no conservatism.

4. The normal dive should only be around 59min total RT to surface without
deep stops using straight Buhlmann (40 mins deco at 1.2 the whole way,
faster with 1.6 at 20ft). With GF (20-100), total RT should be around 64min
total RT (44 mins deco).

5. The OC bail-out plan should only be around 90min total RT if bail-out
right after 20min RT at 300ft using straight Buhlmann (70 mins deco).

-Phi
http://oxycheq.com/DecoWeenie.html
http://groups.yahoo.com/group/PalmPlanner
(Program/Manual in the "Files" section)

-----Original Message-----
From: George Morris

Hi guys.

For all the conspiracy theorists out there, this is what the profile looks
like at a 1.3 set point and zero conservatism. Please note the deco time.
Remember the decent time was 15 mins which alters the gas loading VERY
considerably.

               Zplan v1.03
  (c) Copyright 1997-98, William M. Smithers

                DIVE PLAN

Waypoint  at  300ft for   5:00 (20) on Trimix 8.0/60.0 Dil, Setpoint 1.30,
END 115
Deep Stop at  190ft for   2:00 (26) on Trimix 8.0/60.0 Dil, Setpoint 1.30,
END 69
Deep Stop at  140ft for   2:00 (29) on Trimix 8.0/60.0 Dil, Setpoint 1.30,
END 48
Deep Stop at  120ft for   2:00 (32) on Trimix 8.0/60.0 Dil, Setpoint 1.30,
END 40
Deep Stop at  100ft for   2:00 (34) on Trimix 8.0/60.0 Dil, Setpoint 1.30,
END 32
Norm Stop at  70ft for   2:00 (37) on Trimix 8.0/60.0 Dil, Setpoint 1.30,
END 20
Norm Stop at  60ft for   4:00 (41) on Trimix 8.0/60.0 Dil, Setpoint 1.30,
END 16
Norm Stop at  50ft for   4:00 (45) on Trimix 8.0/60.0 Dil, Setpoint 1.30,
END 12
Norm Stop at  40ft for   6:06 (51) on Trimix 8.0/60.0 Dil, Setpoint 1.30,
END 9
Norm Stop at  30ft for   8:06 (60) on Trimix 8.0/60.0 Dil, Setpoint 1.30,
END 6
Norm Stop at  20ft for  39:00 (99) on Trimix 8.0/60.0 Dil, Setpoint 1.30,
END 3

TOTAL DECO TIME: 71 minutes.
DIVE RUN TIME: 99 minutes.
CNS Total: 43.5%
OTU's: 116


Here's the gas change to 10/50 for OC bailout at the end of the bottom
interval. Discount the 1 minute I've added as anyone aware of the situation
would be headed for the surface already.

300	20	8	60	15	20	0.81	0.7	141
300	1	10	50	20	21	1.01	0.7	35

170	1	10	50	25	26	0.62	0.4	5
160	1	10	50	27	28	0.59	0.4	2
150	1	10	50	28	29	0.56	0.4	2
140	1	10	50	29	30	0.53	0.4	4
130	1	10	50	31	32	0.50	0.4	2
120	1	10	50	32	33	0.46	0.4	2
110	1	10	50	33	34	0.43	0.4	3
100	1	10	50	35	36	0.40	0.4	2
90	2	10	50	36	38	0.37	0.4	3
80	4	10	50	38	42	0.34	0.4	7
70	4	10	50	43	47	0.31	0.4	5
60	7	10	50	47	54	0.28	0.4	8
50	10	10	50	54	64	0.25	0.4	11
40	16	10	50	65	81	0.22	0.4	14
30	26	10	50	81	107	0.19	0.4	20
20	43	100	0	107	150	1.62	0.4	28
0				151

Total OC gas required is 90cu/ft of 10/50 and 28cu/ft of O2. This is
absolutely worst case as it presupposes 6 minutes of bottom time at 300
instead of the 5 planned after the slow descent, and it also presupposes
that the 1.3 set point was not maintained on bottom.

Feel free to pick holes... I'm not presenting these numbers as something I
would personally run, but they are certainly representative of current deco
program output.

George

-----Original Message-----
From: Adam Volosik

Hey Art, think about this, it was mentioned I think twice in the report
about a bailout plan. How do you bail out of a 300' CCR dive while only
carrying (1) Al 80 w/ 10/50 and (1) Al 40 w/ O2? If the rebreather was
mal-functioning how do you decompress with those gases on open circuit?

Adam Volosik


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