How Do YOU Use Your Deco Planning Software?

[Jax]

I’ve been lurking around the I’net and am finding that people use their deco planning software differently, “use” in both a physical and mental way.

• Some take the output of their software as absolute gospel, from which one dare not stray.

• Some use the software to get a dive plan with the most they can “get away with” on the gas they have.

• Some put in a desired plan, and then tweak it – the software is a tweaker for their own plan.

• Some use the software’s plan to hand over to a dive op that requires it, then blow off the plan and follow their computer.

Then, physically, how do you use the results?

• Do you transcribe your plan and its deeper-longer-both plans on a slate for reference? on a wrist slate?

• Do you memorize it?

• Some print and slap a piece of clear packing tape over it – lasts for one dive, all they care about.

• Do you insure everyone on the team has a copy in whatever means they prefer to use?

• Does everyone agree on the plan specifics before it becomes the plan, or is it kind of ‘wing it’?

Background

Some friends dove the Oriskany, and when on their second day, another tec diver was alone, they said, “Hey, he can come with us.” The guide looked at them wide-eyed and said, “You tech divers never want to change your plan!” (in this case, adding a 3rd diver)

Seriously?

 

[MXGratefulDiver]

First off I'll admit I haven't done a real honest-to-God deep dive requiring deco gasses since last Thanksgiving ... so I've been kinda getting away from that whole aspect of diving.

However, during the three or so years when I was doing them regularly it went something like this ...

- Figure out how deep we're going
- Decide how long we want to stay there
- Determine what gasses we're using
- Plug all that into V-Planner and see what it comes up with
- Disregard everything it tells me and come up with a ratio deco schedule that I like
- Go diving

Second set of questions ...

- I'd usually write the schedule in my wetnotes for reference ... after doing a few "standard" schedules (e.g. 200 feet for 25 minutes), I no longer needed the reference. But it's nice to know it's there.
- Absolutely discuss it with the team ... and everyone MUST agree to the plan or we don't go
- In the event that something happens where we have to modify the plan during the dive, the designated leader calls the stops ... and we have a little wetnotes conference once we get on our first deco gas.

... Bob (Grateful Diver)

 

[MauiScubaSteve]

Now please keep in mind that I'm just sayin'......

It would seem that recent threads by the OP might lead this thread to the forum one down on the matrix....

 

[ianr33]

I'll use software to make sure I have enough gas for the plan and any reasonable contingency. Plan ,a worse case contingency (maybe +5 minutes,+20 feet) and a lost gas plan goes on wetnotes in a pocket.

Then I do the deco my Predator tells me to.

First backup is to follow buddies computer (with some padding)

Second backup is tables and bottomtimer.

 

[String]

Play with bottom/deco times while looking at gas margins. Settle on one that allows it with the calculated reserves. Look at the profile and "smooth" it if not happy with the output. Manually add deeper stops using GVE or similar. Re-calculate and check gas volumes with the additions.
If its all OK then write onto a slate and go dive it.

Sometimes have to adjust for gases actually available and fill pressures possible as opposed to what is desired.

If the other people getting in the water are all happy with the same plan then we all dive it. If not then who cares - all use your own plan and probably meet up on the shallow stops.

 

[Ste Wart]

This is my general dive planning:

Computers/ Timers:I carry an Uwatec Gauge Timer and a Suunto Vytec (on extended range this is set for deco, on TMX it's in gauge mode)

Slates/ Deco Schedule: If it's Extended range everything goes on my Wrist slates (the flip-over wrist style one). If Trimix, schedules A&B are printed off, laminated together, bungeed and then go on the wrist. If it's a mega trimix a plan C will be printed off, laminated and stuck in a pocket.

Dive Software: Decoplanner 3.1.whatever
Change a few preferences: 1: Run Buhlmann zhl 16B (tables Buhlmann, 16c is computer. You get a marginal change in schedule between the 2.) 2: Last stop depth 6m; this means my deco is over after this stop, doesn't mean I don't then do extra at 3m. 3: Set a high SAC 17 work, 15 Deco (nobody ever died from having to much gas).

I start by having a rough idea of what dive I would like to do. Let's say 50m 20 minutes. That's my plan A. So what I do is I create my plan B first which would be 55m 25 minutes (5 minutes deeper & longer; for bigger dives I cut this margin down, say for a 80m dive it would be 3 deeper and longer). I plug that with all the other factors i.e SAC and then tweak until I get that to the rule of 3rds. Then I minus off 5 from each to set my plan A. So for example if my SAC will only allow me a 24 minute plan B then my plan A will only be 19 minutes.
I've tried running a Plan A, then 2 plan B's (i.e time over and depth over, but both those plans can be rendered useless very quickly if something goes wrong.) Obviously if it's a solid bottom dive, then I don't add depth to my Plan B only time (everyone still with me?)
Still tweaking. I will add in deep stops directly to the program. As this is a Buhlmann based program I'll be penalised for that in later stops, but that's fine. CNS risk is minimal on these sorts of dives, and a few extra minutes on 50% is nothing to be worried about.
Now happy with the plan I'll transfer it to the slate. If I'm on my own I'll keep things pretty much as gospel; if I'm diving with another, then I'll add a minute onto gas switches (this allows signaling, stowage, monitoring etc etc). Regardless of diving solo or in a buddy pair, I will then add 5 minutes extra at 3m even though my deco is finished just for an added safety margin.
If the Vytec is being used as a back-up I will also make sure that it has cleared as well.

 

[ajduplessis]

I use the software (vpm-b & buhlmann GF) only as a guide and then recalculated every bit of data on paper. I will then the look at the dive profile and based on how I feel modify the shape to what I feel comfortable with on that specific dive. This information is then added to my slate. I will execute the dive piloting 2 dive computers and “cut corners” to make the dive more “conservative” (shallower, less time etc). Gas planning is double checked, blended myself and analysed before every dive.

 

[Cave Diver]

I’ve been lurking around the I’net and am finding that people use their deco planning software differently, “use” in both a physical and mental way.

How did the instructor teach the use of it? I would recommend sticking to that and saving tweaks until a fuller understanding is reached of the effects of different profiles and gases on the deco.

 

[Jax]

Now please keep in mind that I'm just sayin'......

It would seem that recent threads by the OP might lead this thread to the forum one down on the matrix....

:huh:

:headscratch:

 

[ScubaFeenD]

How did the instructor teach the use of it? I would recommend sticking to that and saving tweaks until a fuller understanding is reached of the effects of different profiles and gases on the deco.

Agreed. It doesnt matter how WE use it as long as you are comfortable with how YOU are using it based on what youve been taught and how you feel when you dive.