Incident due to battery change on dive computer

[KenGordon]

You think computer versus tables is more analogous to car-with-auto versus car-with-stick? Auto vs stick seems like Rec PDC versus Tech PDC (in Tech mode).

Riding a motorcycle is a totally different skillset to accomplish the same end as driving a car (i.e. getting from A to B). Using tables is a totally different skillset to accomplish the same end as using a PDC (i.e. diving without exceeding NDLs).

I don't see any reason whatsoever to require people to demonstrate proficiency in operating a motorcycle in order to be licensed to drive a car.

I also don't see any reason to require people to demonstrate proficiency in dive using tables in order to be able to do Recreational diving using a PDC. If they follow their training, the worst thing that will happen is that they will miss out on some diving when their computer croaks and they don't have a backup. And if they don't follow their training, it doesn't really matter what tool they were using. If they aren't going to pay attention to their computer and ascend when it tells them, surely you don't think they will carry a note of (or remember) what their NDL time is and then pay attention to that and a bottom timer, do you?

While I am definitely in the using a computer camp I think it is useful if people understand what the computer is doing. On the other hand we want diving to be accessible to people that can't do calculus at all let alone in their head while narc'd.

Really the goal should be that people know enough to notice they did the planning in feet rather metres or vice versa. Of course if divers don't plan then it doesn't matter if they didn't plan with tables or a did't plan with a computer.

 

[rhwestfall]

Going back to the OP's initial comment that he had done this dive before, I'd like to know what computer let him do this dive w/o deco obligation...... (obviously something is/was different then)

can anyone run this profile w/o deco as a result? I'd think its got nothing to do with the personal conservatism factor... this was a DECO dive.

 

[stuartv]

While I am definitely in the using a computer camp I think it is useful if people understand what the computer is doing. On the other hand we want diving to be accessible to people that can't do calculus at all let alone in their head while narc'd.

Really the goal should be that people know enough to notice they did the planning in feet rather metres or vice versa. Of course if divers don't plan then it doesn't matter if they didn't plan with tables or a did't plan with a computer.

I totally agree with all of that. I would add that I don't think you have to learn how to use the tables - to figure out pressure groups, calculate RNT, and do the arithmetic to calculate a repetitive dive NDL and subsequent pressure group - in order to understand what the computer is doing. I actually think that if the goal is simply to have a good understanding of what the computer is doing and how that reflects your physiology and biochemistry as a model, getting into the weeds of something called a "pressure group" really kind of obfuscates the subject. Looking at the RDP in just enough depth to see how to identify your intended depth and scan across to see what the max time allowed is could be useful. Many people are visual learners and I think that seeing that part of the table helps some people understand the basic idea of "the deeper you go, the shorter your stay" better.

 

[KeithG]

an interesting situation. the key "learning point" i see is the ability to understand when / how your computer is telling you that you have entered "the deco world".

we have a situation where a diver was using a fully functional computer and was "surprised" about having to make deco stops. this seems odd to me. well embarrassingly stupid in reality.

i have only ever owned 2 different computers, but they were both VERY clear about providing NDL information. my first computer was "rec only" and had several warning inficators about thecapproach of NDL. my current "deco capable" computer clearly reports the number of minutes remaining at the current depth before it hits NDL. there is no way to enter deco unaware.

how did the OP miss this important bit of onfo? this is a key failure point IMHO.

Questions: are there computers that are less obvious than others? maybe deco tech computers?

 

[KenGordon]

my first computer was "rec only" and had several warning inficators about thecapproach of NDL.

I don't think I have ever met a rec (ie no deco) only computer. What make and model was it?

 

[rhwestfall]

I don't think I have ever met a rec (ie no deco) only computer. What make and model was it?

A vast majority of them in the early 90's would "lock out" if you went into deco on the dive (many during, many more after).... I kid you not.... glorified bottom timers

 

[Rich Keller]

Not necessarily. SDI OW doesn't teach tables (unless the instructor chooses to go above and beyond the standards) and PADI OW also has that option as well now.

Unbelievable and in my opinion bordering on criminal. Is it really more important to them to help sell computers then to keep people safe?

 

[boulderjohn]

Unbelievable and in my opinion bordering on criminal. Is it really more important to them to help sell computers then to keep people safe?

This issue has been discussed to death over the past 5 years or more. It is not on topic for this thread. I suggest you review any of the umpteen threads on this topic if you want to go down this path rather than hijack this thread.

 

[Hawkwood]

...From the profile I concluded that it would be equivalent of spending the entire 46 minutes at 70 feet which according to PADI is not a deco dive (on the edge but not over) and would have put me into dive group C after 1-3/4 hours...

If that was your conclusion, you do not know how to use the PADI RDP.

 

[Rich Keller]

This issue has been discussed to death over the past 5 years or more. It is not on topic for this thread. I suggest you review any of the umpteen threads on this topic if you want to go down this path rather than hijack this thread.

How is the use of the computer not on topic? How is using tables, at the very least as a backup, not on topic?