Air integrated computers…backup?

[Hoag]

I come from a background that drills into us that:
"One is zero and two is one."

I had an AI Dive Computer (an Oceanic ProPlus 3) fail and had to abort the dive while on a LOB. Fortunately, the crew was able to lend me a DC for the remainder of the trip. It happened at the start of the 1st dive of the day, and I had been out of the water since about 4pm the day before, so although there would have been some residual N2 loading that was not accounted for, I made a risk assessment that it would have been minimal.

Now, I have a Perdix as my primary DC with a Teric as my backup, both "sync'd" to the same (Swift) Transmitter. I also have an SPG. If either DC fails, I have a back up. If my transmitter fails, I have the SPG as a backup. It would now take a dual failure to knock me out of the water on any given dive.

 

[Centrals]

I have been diving with two non-Al computers + single spg for many yrs but could not recall ever seeing anyone did the same on recreational diving.
Electronic is not infallible.
I have dc failure twice before.

 

[Ontwreckdiver]

Used to have an AI dive computer in console but that proved to be unreliable (Suunto Cobra, enough said), now I use two hoseless AI dive computers from two different mfg, Ratio and SP.

I have been using my Suunto Cobra 1 for over 20 years without a back up and it has never failed me.

 

[Joneill]

I come from a background that drills into us that:
"One is zero and two is one."

I had an AI Dive Computer (an Oceanic ProPlus 3) fail and had to abort the dive while on a LOB. Fortunately, the crew was able to lend me a DC for the remainder of the trip. It happened at the start of the 1st dive of the day, and I had been out of the water since about 4pm the day before, so although there would have been some residual N2 loading that was not accounted for, I made a risk assessment that it would have been minimal.

Now, I have a Perdix as my primary DC with a Teric as my backup, both "sync'd" to the same (Swift) Transmitter. I also have an SPG. If either DC fails, I have a back up. If my transmitter fails, I have the SPG as a backup. It would now take a dual failure to knock me out of the water on any given dive.

I also have a Perdix AI and a Teric, but with 2 transmitters - both computers are synced to both transmitters. I keep my old SPG in my bag as an additional backup. I travel to dive so don’t want to cut dives short or miss dives due to computer or AI issues.

 

[scubadada]

I just returned from a week on the Belize Aggressor IV. One day, the cylinder pressures on my Oceanic VT3 and Shearwater Teric were not available, both on the same transmitter. I used my SPG and finished the dive, uneventfully. As I suspected, the battery of my transmitter had failed and was replaced, with resumption of normal function. For the VT3, you must poll the batteries to check their condition, I had not done that. However, I never received the low transmitter battery warnings from my Teric, which is very disappointing:
View attachment 717991

Disappointing, indeed. Do the dive logs have any indication of a problem?

For the OP, I don't have redundant pressure info and would simply end the dive. Install a new battery or revert to SPG for the next dive.

No, there is nothing in the Teric or VT3 download that reflects the dead transmitter battery. The VT3 has no battery information in the download. The Teric has computer battery information, but no transmitter information.

 

[boulderjohn]

Recommend you use the search function. There have been many threads on this topic.

History is made by those who show up.
--Woody Allen

I saw the truth in that statement many times over my lifetime, especially on committee assignments where the decision made would have been entirely different if certain individuals had not shown up one fateful day.

It happens on ScubaBoard as well. People ask a question like this one, and the first couple of pages set the tone, and that tone is determined by who shows up in those pages. The same question can be answered in different ways in different threads.

This can also be a function of time. About 6-7 years ago, someone started a thread asking tech divers what decompression software they used. I would guess the answers ran about 80% VPM. A couple weeks ago someone who had been out of diving since those days asked the same question on the Cave Divers Forum and was stunned when not a single person favored VPM. What was once the dominant program was now passé.

The same is true for air integration in general. Threads on that topic today are quite different from threads only a few years ago.

 

[BoltSnap]

I have been using my Suunto Cobra 1 for over 20 years without a back up and it has never failed me.

Mine was replaced 4 times I think and I had to pay for the replacements. The last time I refused to pay for replacement based on the lawsuit in the US but I was told to go to hell by Suunto since I am living in Libya not the US now. I have had 2 (or 3) other Suuntos computers (not Cobra) fail and went to the trash bin just the same.

 

[Marie13]

History is made by those who show up.
--Woody Allen

I saw the truth in that statement many times over my lifetime, especially on committee assignments where the decision made would have been entirely different if certain individuals had not shown up one fateful day.

It happens on ScubaBoard as well. People ask a question like this one, and the first couple of pages set the tone, and that tone is determined by who shows up in those pages. The same question can be answered in different ways in different threads.

This can also be a function of time. About 6-7 years ago, someone started a thread asking tech divers what decompression software they used. I would guess the answers ran about 80% VPM. A couple weeks ago someone who had been out of diving since those days asked the same question on the Cave Divers Forum and was stunned when not a single person replied with VPM. What was once the dominant program was now passé.

The same is true for air integration in general. Threads on that topic today are quite different from threads only a few years ago.

There have been very recent threads on this.

 

[inquis]

@scubadada, thanks for the report. What are you using for logs? You might make a feature request.

As a data point for others, Subsurface-desktop shows the transmitter battery status from a Teric download. I believe it's reported as one of three values (normal, low, critical) rather than a voltage.

 

[Belzelbub]

What if?
If the only AI computer fails you lose all the information and call the dive. An spg will let you know the tank pressure and make the ascend easier.
A cheap back up computer will give you all the info for ascend except the tank pressure. But with an additional spg you can carry on the dive if you feel like it.

What if?
If the only SPG fails you lose the tank pressure and call the dive. A spare SPG will let you know the tank pressure and make the ascent easier.

A single gas pressure monitor, whether SPG or transmitter is fine for most dives.