Is this day of NDL diving possible with the Petrel or any wrist computer?

[Chiung]

My old Uemis let me dive these profiles but they've died. My old Uwatec Smart Z comes close but hate the wet contacts. No comment on my new VTX. I will buy a Petrel (or any others - Seabear?) Monday if I can confirm they can let me do the following dive day without going into deco.

All dives on 36%

SI(min) Dive Time (min) Depth (ft)
first 1 20 65
:05 2 20 70
:03 3 20 65
:05 4 15 80
:03 5 20 70
1:00 6 20 60
:03 7 20 70
:05 8 20 65
:03 9 15 70
:05 10 15 65
1:05 11 30 75
:03 12 20 70
:05 13 30 70

Thanks for any help.

---------- Post added May 2nd, 2015 at 10:43 AM ----------

bonus question - will I be able to do back-to-back days of said profiles? Say for 3 or 4 days in a row.

 

[boulderjohn]

Just to be sure I understand--you did 13 consecutive dives with barely enough time between most of them to look around at the surface except for after two of the dives. Your total dive time on those 13 dives was about 4.5 hours. Is that correct?

With the information you have provided, I don't think anyone can answer. How much of the total time of each dive was on the bottom? How much of it was on ascent? I once did a 100 foot dive for 80 minutes with an AL 80. My computer allowed that. Would another computer allow it? Would it make a difference if I told you I was only at 100 feet for a few minutes and spent the rest of the dive exploring the top of the reef in shallow water?

 

[Chiung]

Yes, correct.

95% at those depths.

Thanks for not judging.

Is my understanding correct that the Petrel has a dive planner? If so, can someone simulate these dives and see if it can be done w/o incurring deco obligations?

 

[Centrals]

What is wrong with wet contact?

 

[DiveNav]

.....can someone simulate these dives and see if it can be done w/o incurring deco obligations?

I put those profiles in divePAL (you can download them from the divePAL cloud) and, using the liberal settings (the less conservative one) dive 10 creates a deco violation.

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Dive 13 starts and ends in deco.

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It does not matter what dive computer you want to use. That dive sequence is very aggressive!

 

[tursiops]

As far as I know, the Petrel dive planner only allows the planning of the next dive, not the next 13 dives as the OP would like.

The Petrel uses Buhlmann, so I put the profiles into MultiDeco with 100/100 GFs....not a good idea to ever dive that way, but the profiles are crazy anyway.
I could not get beyond dive #10, because MultiDeco has that as the max number of dives in a sequence.
No deco requirements occurred through dive #10.
However, the gas requirements to do the 5 dives in each grouping with short SIs were substantial: assuming 0.5 cuft/min RMV, 150 cuft are needed for dives 1-5 and 137 cuft for dives 6-10.

As a side note, the PADI RDP for 36% will not even allow the sequence through dive #4.

 

[Imla]

Just out of curiosity... what do you do on these dives?

 

[Keith.M]

I am having a hard time understanding this whole exercise. What is the point?

So if you want to dive these aggressive profiles and you are successful in finding a computer that you can adjust to not put you in to deco for this day, and multiple days and then you do it and get bent. Is it going to give you some sort of satisfaction that you were within the NDL of your computer?

 

[Imla]

When I put it all into decoplanner, with the exception of averaging 5min surfaceintervals. (Can't put in 3mins) I only get a problem with the last dive where it seems to need about 9mins of total deco (7 mins at 3m the rest is travel). This is with 36% Nitrox and Buhlman 20/85. The other dives are within minimum deco.

 

[RJP]

If you're intent on doing those dives irrespective of which computer... simply dive a bottom timer. It will NEVER put you into deco.