alternative air source for newbies....

[Icarusflies]

The boat captain and the instructors told us to get back to the boat either after 1 hour (not the case...) or with at least 500 psi in the tank. Futhermore they want us to start the return to the boat with 1000 psi...

 

[HowardE]

Or it displays wrong information.

Give me a break... like what? Again... You would have to NOT be paying attention to it.

I'm not talking about using an AI computer in a cave, or other overhead envirnoment. I am talking about ocean dives, with a visible surface. Even if you have a total malfunction, and start to run OOA. You'd feel it in your reg... then you do a CESA, and that's that.

If you're afraid of AI computers... then don't get one. But they're pretty darn reliable. Do you know someone who has had a malfunction?

This thread is about alternate air sources anyway... not about the reliability of AI computers. So - if you want to bicker about AI computer reliability... maybe you should start a thread about that.

 

[jbd]

The boat captain and the instructors told us to get back to the boat either after 1 hour (not the case...) or with at least 500 psi in the tank. Futhermore they want us to start the return to the boat with 1000 psi...

There's nothing wrong(I'm not implying that cummings66 said it was wrong) arriving back at the boat with 500 psi in the tank at this point in your diving, or for most recreational diving for that matter. Clearly if a diver is back on the boat with 500 psi in the tank then he/she didn't run out of air. Definitely a good thing.

I would like to reinforce the suggestion by Cummings66 that you do a search on "rock bottom" and also on RMV or respiratory minute volume. These topics will help you understand gas planning which will serve you well as you continue into diving.

 

[halocline]

Why? If your AI computer dies... you abort the dive...

AI computers rely on batteries, transmitters, etc (I was mostly talking about the wireless ones) and there are lots of stories of intermittent signal loss. For an experienced diver, who has confidence that he's generally aware of his gas usage, sure, not a big deal. For a new diver who's very concerned about gas supply, this could be very disconcerting.

Primarily, though, I was responding to the OP's statement that his "AI computer gave him lots of confidence" when in fact an AI computer offers no more data than a regular old SPG, just some calculations about projected gas usage.

 

[HowardE]

AI computers rely on batteries, transmitters, etc (I was mostly talking about the wireless ones) and there are lots of stories of intermittent signal loss. For an experienced diver, who has confidence that he's generally aware of his gas usage, sure, not a big deal. For a new diver who's very concerned about gas supply, this could be very disconcerting.

Primarily, though, I was responding to the OP's statement that his "AI computer gave him lots of confidence" when in fact an AI computer offers no more data than a regular old SPG, just some calculations about projected gas usage.

And... your point is?

I've been diving an AI computer for a while now. I have 200 dives on it. The bottom line is... if there's a problem with an AI computer. Wireless or with a hose... You abort the dive - End of story.

 

[TheRedHead]

I had a problem with an AI Suunto Cobra that has probably not occurred to anyone. If you use it to confirm your air is turned on, you may be in for an unpleasant surprise. A DM turned my air off and cranked the valve a half turn back on the way to the dive platform. I looked at the Cobra while breathing both regs and everything looked fine. At 60 feet, my Apeks stopped delivering air. An analog SPG would show a bounce if the valve is half turned and the Cobra did no such thing. This is not a common occurence, I'm sure, but if you dive long enough, uncommon things happen.

 

[HowardE]

I had a problem with an AI Suunto Cobra that has probably not occurred to anyone. If you use it to confirm your air is turned on, you may be in for an unpleasant surprise. A DM turned my air off and cranked the valve a half turn back on the way to the dive platform. I looked at the Cobra while breathing both regs and everything looked fine. At 60 feet, my Apeks stopped delivering air. An analog SPG would show a bounce if the valve is half turned and the Cobra did no such thing. This is not a common occurence, I'm sure, but if you dive long enough, uncommon things happen.

So are you saying (just for clarification) that you breathed off of your regs (before jumping in) and your pressure didn't drop dramatically when you breathed off of it?

The DM turned your air OFF?!? Did you B**ch slap him/her when you surfaced?

 

[halocline]

And... your point is?

I've been diving an AI computer for a while now. I have 200 dives on it. The bottom line is... if there's a problem with an AI computer. Wireless or with a hose... You abort the dive - End of story.

Howard, I made my point clearly. Since you seem to have missed it, and graciously asked for it again, my point is that it is my opinion that a new diver (which is how the OP described himself) is better off not relying solely on an AI computer, especially a wireless one, for gas info. I'm terribly sorry if this opinion offends you as an AI computer owner.

 

[TheRedHead]

So are you saying (just for clarification) that you breathed off of your regs (before jumping in) and your pressure didn't drop dramatically when you breathed off of it?

Yes, that's what I'm saying. It was cranked back open a half a turn. The regulator breathed normally until about 60 feet. I am uncertain if this result could be duplicated with a lower performing regulator. The ATX200 is awesome.

The DM turned your air OFF?!? Did you B**ch slap him/her when you surfaced?

At first I thought my instructor did it to make my life interesting. I didn't realize it was the DM until after the dive, during the debrief with the instructor.

 

[HowardE]

Again, thank you all for this feed back.

I use an air integrated computer (oceanic pro plus 2), it gives me a lot of confidence about the remaining air that I have. I am very glad to have it.

Mattboy - Here is the OP's computer - it is not a wireless AI computer.

- BTW - I'm not offended - People can dive however they want to.