Question about air integrated computers and transmitters

[Diving Dubai]

Feels like this is the same debate in multiple threads over a very long time. Fundamentally comes down to how much redundancy is necessary to mitigate risk

I would concur:

Unfortunately a lot of the most responses always hark back to the tired old statement of "multiple failure point" tossed in there seemingly to justify their opinion.

If I'm honest, the main reason I never took my spg off originally (once I'd gained personal trust in my TX) was pure laziness. I couldn't be bothered to hunt for the port plugs which I'd put in a "safe place"

I personally see value in having both, not for mid dive, because I've dived enough that for 90% of my dives, my contents gauges are there just to confirm what I already know

The only time I've had a TX failure is down to me ignoring the batt info - leaving it until "next week" to change

When it comes to the argument of all the additional failure point by having an additional spg - their just over hyped.

By basic preventive maintenance in havign gear checked and replacing O rings and hoses in a timely fashion these issues will generally go away.

We as divers accept the need for an Alt reg (octo). Yet they have the same amount of failure points as a conventional SPG, and an LP leak is far more serious. Mathematically the probability of failure is just teh same

You can mitigate out the use of an Octo by a simple Air Share ascent, but this has largely been dismissed as practical because of the greater risk if injury to divers and is not seen as good practice.

I frankly don't' care how people choose to configure their equipment, I just don't like people using "suspect" justifications to ram home their personal point of view as though it's the only way of doing things

 

[Neilwood]

All:
I read some of this thread and am really shocked at some of your answers/responses on wether to use a mechanical pressure gauge if you have ai. I am a pilot and also an airframe and power plant guy. I guess since I have been in aviation we have “redundant” systems. Why for the love of God would you get rid of a gauge on your console and leave everything to chance that your tank pod will not fail? What if it does and you’ve deleted the mechanical gauge? It’s a guessing game at that point on how much air you have left in your tank. A mechanical gauge is not that expensive, you already have a console, why delete it? As for me and my family, we all have air integrated wrist mounted dive computers and we also have console mounted back up computers and air pressure gauges. Hope you guys remain safe. Please think about your choice to delete a gauge because of technology. My 2 pennies worth.

Glenn

You work in industries where safety matters - not just to yourself but to others. You are comparing a recreational sport where ending a dive early would be the correct action to a failure to situations where failures can be catastrophic for more than one person. Even on a solo plane journey, a crash might affect hundreds in a populated area so redundancy matters hugely. Not so much in diving as if the SPG or AI craps out, you make the same choice - surface at a safe speed with your buddy.

As a number of posters have said, do you currently dive with 2 spgs in case of one screwing up? Most probably not. Have you got two first stages on an H valve? Probably not. That would be true redundancy.

For recreational divers, we are trained with one source for checking our air- the SPG. That took a long time to be adopted as the "standard" because people didn't trust them. There were IIRC quite a number of failures before they achieved the current level of reliability. Similar has happened with AI. Early AI had a problem with significant numbers of disconnections etc. That has long since been cured and we are now in a position where AI is almost (to a fraction of a %) as reliable as an SPG. I don't have figures for numbers of failures for SPG's or AI (no-one does AFAIK) but my best guess would be they both have a record of well below 1% of failures per 100 hours diving (if not 1000 hrs). If there is a disconnection, it is likely it will be momentary and resume within a few seconds in which case continue the dive. If it is longer than a minute, IMHO it is time to end the dive.

If you are diving in accordance with your training you should be in the situation of having a pretty good idea of how much gas you have at any point in a dive to the extent that you are using your SPG/AI to verify your expected gas level. Checking the SPG is only to verify the dive is proceeding in accordance with the plan. For a 30 min dive, with 200 bar in the tank, I know that at 10 mins I should have used 50 bar (give or take due to currents etc), 20 mins=100 bar with ending the dive @150bar used. If you like the SPG/AI is your redundancy - if you are diving properly it should only verify what you should already know.

 

[jlcnuke]

All:
I read some of this thread and am really shocked at some of your answers/responses on wether to use a mechanical pressure gauge if you have ai. I am a pilot and also an airframe and power plant guy. I guess since I have been in aviation we have “redundant” systems. Why for the love of God would you get rid of a gauge on your console and leave everything to chance that your tank pod will not fail? What if it does and you’ve deleted the mechanical gauge? It’s a guessing game at that point on how much air you have left in your tank. A mechanical gauge is not that expensive, you already have a console, why delete it? As for me and my family, we all have air integrated wrist mounted dive computers and we also have console mounted back up computers and air pressure gauges. Hope you guys remain safe. Please think about your choice to delete a gauge because of technology. My 2 pennies worth.

Glenn

How many fuel gauges do each of your fuel tanks have in your cockpit?