When computers fail

[sharpenu]

There is a recurring comment that I hear on this board and in other places that I disagree with, and I would like to state my opinion and see what all of you think. I am referring to gas integrated computers. The comment usually goes like this:
"I wouldn't buy an integrated computer, because if it fails, you lose all of your guages, and then where are you? Your diving day is done!"

Here is my view on that:
1 Look at the manual for your computer. Integrated or not, in the event of failure, they all say to ascend to 15 feet and stay there as long as possible before surfacing. Integrated or not, computer failure=dive is over

2 You can't just revert to the tables. Here is a profile from my last trip to Boynton Beach: (on air, not nitrox)
66 feet for 51 minutes, 1 hr 10 minute interval, then 62 feet for 40 minutes. If your computer were to fail at any time after the first 10 minutes of the second dive, it puts you off the tables. Computer failure= day of diving is over. Integrated or not.

I know there are people who say they won't trust their life to a machine, but like it or not, unless you are freediving, SCUBA by it's very nature is a sport where your life is at the mercy of machinery, whether it is mechanical or electronic.

That is my opinion, what do YOU think?

 

[detroit diver]

Computers are nice, but not perfect. I always have a written backup done by manually doing the tables. Keep it as a wetnote or on a wrist slate.

I might mention (with the full realization that the flames will shoot out) that I am working on diving DIR, and computers are not allowed for the exact reasons mentioned previously. They want you to be so familiar with where you are in relation to time/depth/deco that you are always prepared. Dive/deco schedules that take into account time overages, missed stops, etc.

Your brain is a much better computer. You just have to use it.

 

[sharpenu]

Understood, but how do you deal with the dive profile mentioned in the first post? I got my computer to extend my dive times. Do you find the tables too restrictive?

 

[bradymsu]

1. You're right in that if your computer should fail and you're outside of the tables, you're done for the day. However, you wouldn't even have been able to dive for as long as you did to get outside the tables if you were only using tables in the first place.

2. I agree that the human brain is much more powerful than a computer in the overall "we only use 5% of our brain" sense. After all, humans designed them. However, my Suunto is far more powerful and accurate in making instant and percise calculations than even the most brilliant and careful human mind. Computers don't make errors, people do. As Detriot Diver mentioned, my solution also is to plan my dive by hand and dive my plan with a computer, actually two of them.

 

[Lost Yooper]

The problem with computers is the dependancy that inevitablely ensues (similar to the pony bottle issue). For deco diving, most computers are more conservative (unnecessarily so) than good quality computer generated tables. On top of that, most (if not all) computers don't know how to decompress you "correctly". The wireless 'puters seem to do all of this, but with a jaw dropping price tag (actually, I don't know what they cost anymore).

Basically, I'm not all that against computers for recreational diving. However, I say that in the context that I know more about decompression than the computer does,and I can manipulate the dive to make sure I come out feeling good. Computers can be convenient for repetitive recreational dives, but they aren't really needed if you know more than the computer does.

Mike

 

[detroit diver]

I don't have any of my stuff at work, but my answer would be to use the computers on dry land, do your variances, and copy them to paper/slate/wetnotes. There's a bunch of programs that you can modify to your own risk (comfort) levels.

If you've got the info with you, the computer can do whatever it wants and you won't be slowed down.

It takes a little more planning and observance to that plan.

 

[large_diver]

If you are rec diving (single dive) and want a quick rule to follow if your computer fails, you can always use the "120" rule:

Your bottom time and depth should not add up to more than 120.

It's not as precise as using tables, but in a pinch, it should keep you safe.

 

[retnug]

My thoughts. I have been one of those that has said something to the effect of... "when an air integrated computer fails you lose your pressure gauge along with it." Don't get me wrong I dive a computer but I don't have air integration. So when my computer fails, and I have had that happen, I still know how much air I have. I think that is an important factor when you are trying to end a dive safely after a computer failure. If you have an air integrated computer and an SPG then this wouldn't be a problem. But I haven't seen many diver with an air integrated computer and an SPG. They usually eliminate the SPG in favor of the computer.

G

 

[sharpenu]

True, IF the computer fails, you have no SPG. The point I am making is that the dive is over anyway. Let's be honest. The chances of a sudden failure are close to the odds of your first stage failing. Or your mask breaking. While you may have a redundant air supply, how many of us have a spare mask at 100 feet? What if the boat sinks? I guess I am trying to say that with the reliability of today's computers, the chances of computer failure are so small as to bring them to an acceptable level. The statement that you are smarter and less likely to err than a computer (made by some here) is the type of attitude that keeps me employed. Like it or not, we trust our lives to computers every day. Does your car have ABS? Do you fly to your destination?

 

[Norm]

It's enevitable: Sooner or later, if you dive enough, you're probably going to lose your computer's function. I've had nearly ten different computers and eight of them have failed.
One failed at 139' - it blinked and suddenly started telling me that I had nearly ten hours of bottom time left!
I have to agree with detroit diver, Lost Yooper and large_diver. I primarily dive my tables and use a computer for "back up".
It's nice for the added bottom time on repetitive dives, (and I do use it/trust it over what the tables tell me for those), but I do know how to decompress up and get myself out of the situation in case of a total failure.
I will always use a full console with an added computer. I've been in Caymans when a friend's hoseless computer wigged-out. He had three options: Buy a system down there, rent for the duration or stay out of the water.
If you know the tables you always know about what you're good for, and it's easy to do: On the old Navy tables, (which I've lived by for many, many years/dives), start in the middle using 60' for 60 minutes and work inversely each direction. (Makes memorizing them much easier!) Just my opinion and it works well for me!