Incident due to battery change on dive computer

[boulderjohn]

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

What is not on topic is arguing why not teaching tables in modern computer instruction is wrong. This is an accident and incident forum. Any discussion needs to be directly related to the specific incident that spawned this discussion.

 

[DiveNav]

from pure tables (square profile) - that is a 95' dive for 40 minutes.... DECO! In reality, something different.....

0-3 minutes - descent to 95'
3-5 minutes @ 95'
5-6 minutes - ascent to 66'
6-40 minutes @ 66'
40-48 minutes ascent to SS & Surface....

Lets see if Alberto can quickly put it into DivePal or someone can input it into something else.....

Here you go ....

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profile is also on divePAL cloud.

In my book it is an aggressive dive (at least for my old age).

 

[DiveNav]

.......I'd think its got nothing to do with the personal conservatism factor... this was a DECO dive.

It depends on how you look at it ..... see analysis

​

 

[KeithG]

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

I think the key topic is to have understand basic NDL theory and then being able to follow your computer (or tables) to either stay out of deco or to fulfill your planned deco obligations. This did not happen.

The OP appears to have ignored his computer. I assume he would also have ignored his bottom timer / depth guage. Tables or computer would have the same result.

This appears to be a case of a trust me dive where "me" is really "my faulty memory".

The OP had a functional computer and choose to ignore it. Even worse, he was surprised by it!

---------- Post added April 10th, 2015 at 07:29 PM ----------

P.S. I think the title of this thread should be "Incident due to ignoring computer".

 

[MMM]

I always dive with two computers. I figure that the chances of one failure is low but possible. But that the chance of both failing is almost non existent. Maybe that is a learning here to prevent a possible recurrence.

 

[rhwestfall]

I always dive with two computers. I figure that the chances of one failure is low but possible. But that the chance of both failing is almost non existent. Maybe that is a learning here to prevent a possible recurrence.

But there was no failure of the device in regard to proper function.

I once was carrying a spare pdc in my pocket on a dive. Upon surfacing, it became apparent I had bent it by 1 minute. Other computer said all was well....

 

[dmoore19]

Maybe the OP wasn't familiar with the display of the computer during the ascent. I have the dive computer training that DivNav's company put out for my computer. During the viewing of the course it shows what the computer display will be. Knowing what it is telling you is absolutely necessary IMO. I turn the alarms off so as not to bother others, besides I am older and can't hear them anyway.

If the OP were to post the computer recorded profile it might give further insight into the situation he was in.

 

[KeithG]

Maybe the OP wasn't familiar with the display of the computer during the ascent.

That would be a fail on the divers behalf.

If the OP were to post the computer recorded profile it might give further insight into the situation he was in.

I believe there is an image of the dive profile posted above. But who cares what the profile is? The issue is not a "broken" computer.

The computer said he was in deco - and it was a surprise - how did that happen?.

 

[SubAquatix]

FWIW, assuming I read the data right, both MultiDeco and DecoPlanner would have called this a Deco Dive on Air (Buhlmann 16B, 20/85)

 

[kwinter]

FWIW, assuming I read the data right, both MultiDeco and DecoPlanner would have called this a Deco Dive on Air (Buhlmann 16B, 20/85)

Yes, but by playing with some factors, I did manage to get it to be just over 5 minutes of deco at 10 feet. That is basically a safety stop. Of course the factors were an EXTREMELY aggressive ascent. Something I would never even think to do unless a dire emergency. A 5 minute dive to 95 feet followed by a slow, gradual rise could be done without deco. But staying at 70 feet for that length of time and not putting in any stops is just nuts, regardless of what a computer tells you.