Offboard 02 for the mCCR

[CaptnJack]

70mins of deco? Jeesh for that kinda BT I would have done 20-25 (on OC), how on earth did you rack up that much deco in 12mins?

70 minutes was total run time including descent

D'oh. Yeah. I can't remember how much runtime we had when we started the ascent, but I think I'm close. And yes, I cleared at 70 minutes.

Damn. Good thing you didn't actually get a decent BT time in, you'd still be out there finishing your deco.

[dsteding]

Damn. Good thing you didn't actually get a decent BT time in, you'd still be out there finishing your deco.

VPM with 12 minutes at 290 gives 88 minutes of deco with a setpoint of 1.3. Not making that up.

[CaptnJack]

Damn. Good thing you didn't actually get a decent BT time in, you'd still be out there finishing your deco.

VPM with 12 minutes at 290 gives 88 minutes of deco with a setpoint of 1.3. Not making that up.

What diluent? What the hell do you get for 20 or 25mins BT? Is it counted in days or weeks?

[dsteding]

Damn. Good thing you didn't actually get a decent BT time in, you'd still be out there finishing your deco.

VPM with 12 minutes at 290 gives 88 minutes of deco with a setpoint of 1.3. Not making that up.

What diluent? What the hell do you get for 20 or 25mins BT? Is it counted in days or weeks?

I put in 10/55, Just guessing. 20 minutes of bottom time is four weeks of deco, you get a sandwich for lunch too.

[Joshua Smith]

Pretty close. It was more like 12/60. What's the big deal? You do the depth, you do the time, right?

[dsteding]

Pretty close. It was more like 12/60. What's the big deal? You do the depth, you do the time, right?

I don't see the big deal--actually sounds reasonable (I don't know Jack about those types of dives). That is why I ran it in V-Planner, just to see what total runtime is.

Richard is being the deco

[Joshua Smith]

To answer the question-

290 feet, 12/60 dil, 1.3 sp

15 minutes bt, including descent = 85 min Runtime

20 minutes= 121 min RT

25 minutes = 154 min RT

(I could have sworn Richard said he had a copy of vplanner.....)

[dsteding]

To answer the question-

290 feet, 12/60 dil, 1.3 sp

15 minutes bt, including descent = 85 min Runtime

20 minutes= 121 min RT

25 minutes = 154 min RT

(I could have sworn Richard said he had a copy of vplanner.....)

Question: do you run a constant PPO2 on ascent as well? I assume your computer monitors? Reason I ask (and I don't have V-Planner in front of me) is that switching to a higher PPO2 and/or switching to a lower helium mix would lessen that deco considerably.

[Joshua Smith]

Yes, we do. But dives like this start pushing the CNS clock pretty hard- that last 25 minute profile is at 84%. I'd rather not try and game the system very much- that way I have some margin of CNS exposure left over for the chamber, if I need it.

[dsteding]

Yes, we do. But dives like this start pushing the CNS clock pretty hard- that last 25 minute profile is at 84%. I'd rather not try and game the system very much- that way I have some margin of CNS exposure left over for the chamber, if I need it.

Makes sense, although I wonder how valid the CNS clock is.

These dives are interesting to me because of the exposure time in a dynamic environment.

[Joshua Smith]

These dives are interesting to me because of the exposure time in a dynamic environment.

Uh.....Yeah! I find them more interesting than my pool dives, for example. Of course, the pool can be pretty darn dynamic, too, if you don't clear out before the seniors lap swim.

[CaptnJack]

To answer the question-

290 feet, 12/60 dil, 1.3 sp

15 minutes bt, including descent = 85 min Runtime

20 minutes= 121 min RT

25 minutes = 154 min RT

(I could have sworn Richard said he had a copy of vplanner.....)

I do have vplanner, but without knowing your diluent had no way of knowing what to put in.

20min BT on 12/60 OC, gets you 30mins on O2, 30mins on 50%, and 15mins on 35/25, 7 min ascent from 190-130ft, plus roughly 4 mins to get to 190. Total ascent for a 20min dive = 86mins = roughly VPM +2. I'm not doing this dive, but if I were I would probably pad the O2 by 10mins, but it would still be <100mins runtime. It would not be a cheap dive.