ianr33
Contributor
I am planning a dive I hope to do later this month. Profile is 110 max for 40 minutes then 80 feet for 10 minutes. Using 32%. From V-Planner:
Surface interval = 1 day 0 hr 0 min.
Elevation = 0ft
Conservatism = + 2
Dec to 110ft (2) Nitrox 32 50ft/min descent.
Level 110ft 37:48 (40) Nitrox 32 1.38 ppO2, 90ft ead
Asc to 80ft (41) Nitrox 32 -30ft/min ascent.
Level 80ft 10:00 (51) Nitrox 32 1.09 ppO2, 64ft ead
Asc to 20ft (53) Nitrox 32 -30ft/min ascent.
Stop at 20ft 6:00 (59) Nitrox 32 0.51 ppO2, 13ft ead
Stop at 10ft 11:00 (70) Nitrox 32 0.42 ppO2, 4ft ead
Surface (70) Nitrox 32 -30ft/min ascent.
OTU's this dive: 77
CNS Total: 30.8%
142.1 cu ft Nitrox 32
142.1 cu ft TOTAL
This is an open water,wall dive.
Going to be using double Al 80's. Looking at the above it is obvious that to allow a safe reserve we will need to carry an extra 80 stage.
Am planning on breathing the stage first , taking it down to 1000 psi then switching to backgas.
The thinking behind this is that 1000 psi in the stage would be enough gas (just) to ascend and do deco in the rather unlikely combination of losing all backgas and my buddy as we end our bottom time.
Does this sound reasonable or is it certain death
Surface interval = 1 day 0 hr 0 min.
Elevation = 0ft
Conservatism = + 2
Dec to 110ft (2) Nitrox 32 50ft/min descent.
Level 110ft 37:48 (40) Nitrox 32 1.38 ppO2, 90ft ead
Asc to 80ft (41) Nitrox 32 -30ft/min ascent.
Level 80ft 10:00 (51) Nitrox 32 1.09 ppO2, 64ft ead
Asc to 20ft (53) Nitrox 32 -30ft/min ascent.
Stop at 20ft 6:00 (59) Nitrox 32 0.51 ppO2, 13ft ead
Stop at 10ft 11:00 (70) Nitrox 32 0.42 ppO2, 4ft ead
Surface (70) Nitrox 32 -30ft/min ascent.
OTU's this dive: 77
CNS Total: 30.8%
142.1 cu ft Nitrox 32
142.1 cu ft TOTAL
This is an open water,wall dive.
Going to be using double Al 80's. Looking at the above it is obvious that to allow a safe reserve we will need to carry an extra 80 stage.
Am planning on breathing the stage first , taking it down to 1000 psi then switching to backgas.
The thinking behind this is that 1000 psi in the stage would be enough gas (just) to ascend and do deco in the rather unlikely combination of losing all backgas and my buddy as we end our bottom time.
Does this sound reasonable or is it certain death