Recent Opinions On Air Integrated Computers For Technical Diving

[Lostdiver71]

Me personally, I have seen too many issues with AI units to ever dump the money on one. I mean an additional $300-500 to add a sensor so I don't have to take 2 seconds to look at my SPG?

I can also only monitor 1 thing, if I am carrying 3 gasses, I have no way to monitor all of them with one computer, bringing me back to having to check SPG's anyways.

Lastly, Since I'm sure the comment is coming, yes an SPG can break also. A replacement SPG is $40 vs a $300 transmitter.


YMMV.

Actually most WAI computers can monitor multiple gasses, I currently use my older Aeris computer to monitor my primary and backup or decompression gas using multiple transmitters. It also switches gases automatically when it detects me breathing off of the regulator.

 

[JohnnyC]

It also switches gases automatically when it detects me breathing off of the regulator.

What does the computer revert to in a failure condition since it's auto switching? By this I mean, what does it do when it detects multiple tanks dropping pressure, say in a state where you have an undetected leak on your 50% bottle on a leash, while breathing your backgas? Does it assume you are breathing your backgas or your 50?

 

[Fires]

I have only just started on my tech journey and of course for the get go have been advised against AI. As many have already said it is an additional failure point but it can also be a snag point (unless you can mount it down and tucked away. Which is where I feel (down and tucked away) it might get more damaged/squished.

So far I have been using AI (right post) and SPG (standard left post) just to get a closer overview of SAC rates. Not sure if this will become a constant thing. The redundancy is nice I guess, but yeah, another failure/snag point.

 

[John C. Ratliff]

Your main question was answered well by @JohnnyC , so I'll not repeat his points, but I'll venture to add a few thoughts of my own. (Mine are based on a Shearwater Perdix AI because that's what I dive.)

re: which tank pressure displays where -- The transmitter-to-display pairings on all dive computers are constant and unchanging. On my Perdix, the tank readouts are labeled T1 and T2; pairing the transmitters to the computer locks those T1/T2 associations. Unless the computer breaks, the left tank pressure will always show up on T1 and the right tank pressure will always show up on T2. (And if the computer breaks, I've got bigger problems.)

The human factor (i.e., putting the wrong transmitter on the wrong tank) is also not a problem because sidemount diving requires different first-stage-and-hose setups on the left and right tanks. Since I can't mistakenly swap the first stages and the attached transmitters, my left tank will always have the T1 transmitter, and my right tank will always have the T2 transmitter.

re: checking tank pressures frequently -- When tank pressures are off by about 500 psi, side-to-side tilt becomes highly noticeable; thus, a sidemount diver needs to swap second-stage regulators frequently. My SM instructor recommended swapping every 400 psi. Also, because of that frequency, being able to check pressures with minimal effort becomes important, and my Perdix makes that a breeze because the display is always lit up. An SPG, on the other hand, has no inherent luminosity, and an SPG's face needs charging with a light before it's readable in the dark.

since you side mount divers are swapping second stages so often, I'm curious as to whether you have thought of using some of the older Scubapro second stages that allow both left- and right-hose hookups, as this would allow you to hook up one second stage to both tanks, and use air simultaneously from both tanks? It seems that this would be a better option that switching second stages every 500 psig.

SeaRat

 

[tbone1004]

since you side mount divers are swapping second stages so often, I'm curious as to whether you have thought of using some of the older Scubapro second stages that allow both left- and right-hose hookups, as this would allow you to hook up one second stage to both tanks, and use air simultaneously from both tanks? It seems that this would be a better option that switching second stages every 500 psig.

SeaRat

they don't draw equally. They will draw from the tank with the higher IP first. If they're close, it won't be all or nothing, but it will be biased towards the higher IP.
Switching every 500psi is excessive in the real world. They teach it during the courses to get the muscle memory down, but even with big steel tanks I usually go 500-600 for the first, then every 1000-1200psi after that. It's certainly not worth having one regulator tied to both tanks.

Which second stages allow for dual input? I've never heard of one before....

 

[Mike1967]

Which second stages allow for dual input? I've never heard of one before....

If there's is such a thing it just sounds like an extra hassle donning and doffing.

 

[Manatee Diver]

As an example of how attitudes have changed, today I was told my a well respected cave instructor to remove my lollipops, not to remove my transmitters. Granted they are being replaced by button gauges, but how long ago it would've been the other way around?

 

[JohnnyC]

As an example of how attitudes have changed, today I was told my a well respected cave instructor to remove my lollipops, not to remove my transmitters. Granted they are being replaced by button gauges, but how long ago it would've been the other way around?

Button gauges are even less reliable than transmitters. Of course you should get rid of the lollipops because curb feelers are super lame, but if you're gonna go with transmitters, just go with the transmitters. If you have a failure you're turning the dive anyway, what do you think you're gonna do when your button gauge shits the bed?

 

[Manatee Diver]

Button gauges are even less reliable than transmitters. Of course you should get rid of the lollipops because curb feelers are super lame, but if you're gonna go with transmitters, just go with the transmitters. If you have a failure you're turning the dive anyway, what do you think you're gonna do when your button gauge shits the bed?

A bit of a when in Rome moment. Once I get full cave and some experience, I might start deviating, but right now I speak Latin.

 

[RayfromTX]

I was told by my instructor to take my button gauges off and replace them with full size spgs so that he could see them on our training dives. This means putting the transmitters pointing up so that the spgs can run down along the tanks. When we aren't on evaluation dives we go back to transmitters down and buttons up.