A friend of mine and I were having this discussion yesterday. We were pondering the advantages and disadvantages of using a computer on decompression dives. I like some input from you guys and gals, as we are currently split in our rational.
My thoughts:
I plan my dives using Deco Planner software. I plan the dive to the max depth expected for the entire bottom time. I print this plan off. I then run two contingency plans. One, for exceeded depth if my max depth planned is not a hard bottom. Two, for exceeded time, in case I extend my bottom time in an emergency. I plan my gass based on the most restrictive of the three, and by the rule of thirds. I plan my dive, dive my plan, and communicate my plan with my team, the boat captain, and the DM if appropriate.
I wear an Uwatec bottom timer as my primary, and my Oceanic VT Pro in gauge mode as my secondary. The Oceanic aslo records the dive for later analysis. I have set times in the dive for descent, out, turn, line, and stops. If I blow the depth or time due to an unforseen circumstance, I flip my slate to the appropriate table and take the penalty.
Since most of these dives are actually multi-level, I loose some bottom time, but gain a safety factor.
His thoughts:
He plans the dive using his computer software, so that he can estimate his gas needs and bottom times. He carries the generated tables with him via a slate. He wears a Nitek as his primary and a bottom timer as his secondary. He dives the profile that his Nitek gives him, allowing credit for multi-level. This is basically how I dive my recreational dives. If the computer fails (unprobable?), he reverts back to the tables. He feels that any extra time the cx afforded by moving to shallower depths will be made up for by reverting back to the original tables calculated at max depth.
Here's the problem as I see it. At any given point in the dive, he knows where he's at in relation to what a piece of equipment is telling him. If that piece of equip gets damaged or fails, then he is in the dark as to what his real deco schedule needs to be.
Am I over anal in thinking this is too much what if and switching to manual reversion? I like to keep it simple and know what my stops are going to be and then make those stops. I have a hard time thinking, OK, now the cx wants a 50' stop, but my tables didn't have a 50' stop.
Sorry for the long post, but I'm looking for some input. He is a great diver, and I thought the same as him until I had logged several deco dives.
My thoughts:
I plan my dives using Deco Planner software. I plan the dive to the max depth expected for the entire bottom time. I print this plan off. I then run two contingency plans. One, for exceeded depth if my max depth planned is not a hard bottom. Two, for exceeded time, in case I extend my bottom time in an emergency. I plan my gass based on the most restrictive of the three, and by the rule of thirds. I plan my dive, dive my plan, and communicate my plan with my team, the boat captain, and the DM if appropriate.
I wear an Uwatec bottom timer as my primary, and my Oceanic VT Pro in gauge mode as my secondary. The Oceanic aslo records the dive for later analysis. I have set times in the dive for descent, out, turn, line, and stops. If I blow the depth or time due to an unforseen circumstance, I flip my slate to the appropriate table and take the penalty.
Since most of these dives are actually multi-level, I loose some bottom time, but gain a safety factor.
His thoughts:
He plans the dive using his computer software, so that he can estimate his gas needs and bottom times. He carries the generated tables with him via a slate. He wears a Nitek as his primary and a bottom timer as his secondary. He dives the profile that his Nitek gives him, allowing credit for multi-level. This is basically how I dive my recreational dives. If the computer fails (unprobable?), he reverts back to the tables. He feels that any extra time the cx afforded by moving to shallower depths will be made up for by reverting back to the original tables calculated at max depth.
Here's the problem as I see it. At any given point in the dive, he knows where he's at in relation to what a piece of equipment is telling him. If that piece of equip gets damaged or fails, then he is in the dark as to what his real deco schedule needs to be.
Am I over anal in thinking this is too much what if and switching to manual reversion? I like to keep it simple and know what my stops are going to be and then make those stops. I have a hard time thinking, OK, now the cx wants a 50' stop, but my tables didn't have a 50' stop.
Sorry for the long post, but I'm looking for some input. He is a great diver, and I thought the same as him until I had logged several deco dives.
