Rec Diving a Pony

[mallbritton]

The pony thread got me to thinking, not sure if this belongs here or in Basic and I didn't want to hijack the recent pony thread.

Let's say I'm REC diving a Pony with a buddy. Can I ditch the OCTO, use the pony as the safe second and streamline my REC setup a bit?

Pretty sure I know how most will respond, but curious for the input regardless.

I haven't read the entire thread, just yet, but my suggestion would no don't ditch the OCTO. When I'm diving with a redundant air supply my attitude towards that tank is "that's my air" and no one else is going to get it. Especially if I'm diving solo.

In your example, unless you have briefed your buddy on emergency procedures involving the redundant air, and practiced those procedures if an actual out of air situation happens they won't know what to do. You can never have too much redundancy.

 

[tbone1004]

You can never have too much redundancy.

yes you absolutely can. If the redundancy ultimately causes issues, in this case increased failure points and unnecessary added complexity to the system, then you have too much redundancy. This is why we don't have 2 second stages on any post in technical diving, why we don't have redundant SPG's, most people don't use dual bladder wings, etc etc. The added redundancy does not add any appreciable improvement to safety, but does in fact add unnecessary complexity. This is the foundation of hogarthian gear configurations and KISS

 

[Edward3c]

yes you absolutely can. If the redundancy ultimately causes issues, in this case increased failure points and unnecessary added complexity to the system, then you have too much redundancy. This is why we don't have 2 second stages on any post in technical diving, why we don't have redundant SPG's, most people don't use dual bladder wings, etc etc. The added redundancy does not add any appreciable improvement to safety, but does in fact add unnecessary complexity. This is the foundation of hogarthian gear configurations and KISS

Considering the number of divers with both primary and secondary on one cylinder, there aren’t a significant number of O-ring failures. The constant regurgitation of failure points doesn’t stack up.

Your configuration works in your limited environment, but the majority of divers dive differently.

 

[mallbritton]

yes you absolutely can. If the redundancy ultimately causes issues, in this case increased failure points and unnecessary added complexity to the system, then you have too much redundancy. This is why we don't have 2 second stages on any post in technical diving, why we don't have redundant SPG's, most people don't use dual bladder wings, etc etc. The added redundancy does not add any appreciable improvement to safety, but does in fact add unnecessary complexity. This is the foundation of hogarthian gear configurations and KISS

All very true. I probably should have added "within reason."

 

[rjack321]

yes you absolutely can. If the redundancy ultimately causes issues, in this case increased failure points and unnecessary added complexity to the system, then you have too much redundancy. This is why we don't have 2 second stages on any post in technical diving, why we don't have redundant SPG's, most people don't use dual bladder wings, etc etc. The added redundancy does not add any appreciable improvement to safety, but does in fact add unnecessary complexity. This is the foundation of hogarthian gear configurations and KISS

Considering the number of divers with both primary and secondary on one cylinder, there aren’t a significant number of O-ring failures. The constant regurgitation of failure points doesn’t stack up.

Your configuration works in your limited environment, but the majority of divers dive differently.

@tbone1004 is correct, Many divers have perished with a clustereffery of regs and valves and gas actually on them. But in the process of fumbling through the mess they drowned. Or one part failed but they dove anyway (because of all the other redundancy) and then more pieces failed to the point of being a confusing mess and they drowned or more commonly bolted and embolized.

 

[tbone1004]

Considering the number of divers with both primary and secondary on one cylinder, there aren’t a significant number of O-ring failures. The constant regurgitation of failure points doesn’t stack up.

Your configuration works in your limited environment, but the majority of divers dive differently.

limited environment?
The majority of my diving is cave diving, however, I regularly teach in cold lakes and quarries, and I just got back last night from diving offshore wrecks in NC. I love doing warm water reef diving. What am I missing? When I dive single tank, I have 2 second stages on one post obviously, but the discussion is about redundant configurations, and the only time you see 2 second stages on a first stage in a redundant system is when recreational divers are using pony bottles. Never in sidemount, twinsets, or rebreathers. If the argument to hold both second stages on the primary gas supply held water, then we would have them on our technical configurations, but it doesn't.

 

[rjack321]

limited environment?
The majority of my diving is cave diving, however, I regularly teach in cold lakes and quarries, and I just got back last night from diving offshore wrecks in NC. I love doing warm water reef diving. What am I missing? When I dive single tank, I have 2 second stages on one post obviously, but the discussion is about redundant configurations, and the only time you see 2 second stages on a first stage in a redundant system is when recreational divers are using pony bottles. Never in sidemount, twinsets, or rebreathers. If the argument to hold both second stages on the primary gas supply held water, then we would have them on our technical configurations, but it doesn't.

As an example of an especially bad configuration seen in the wild.

FFM on primary tank, long hose on primary tank (for buddy or yourself). Pony bottle with clipped off 2nd stage. 2x 1st stages and 3x second stages. Now its not unheard of for a 1st stage to fail or become blocked with debris. If that happens to the primary tank's 1st stage, you are ditching the FFM to change to another reg. But of course you are doing this in anger and can't exactly see, and if in frigid water have a abrupt mammalian instinct to breath too. The pressure gauge still shows that the main tank has gas in it (if you can see that) but you've got to fumble between 2nd stages half blind. Pick the wrong one and by the time you sort it out drowning is a distinct possibility. I know tbone knows this, but its just one example where more is not actually helpful.

 

[Edward3c]

limited environment?
The majority of my diving is cave diving, however, I regularly teach in cold lakes and quarries, and I just got back last night from diving offshore wrecks in NC. ... What am I missing?

You’ve answered it for me.

 

[Zef]

Considering the number of divers with both primary and secondary on one cylinder, there aren’t a significant number of O-ring failures. The constant regurgitation of failure points doesn’t stack up.

Your configuration works in your limited environment, but the majority of divers dive differently.

How I wish I could hit like more than once.

The divers making the "failure point" argument seem oblivious to the notion that the arguments they make seem especially specious as they strive to eliminate "failure points", because of their perceived risk of them, so that they can dive in environments with a very real amount of increased risk for mostly recreation purposes.

I have witnessed a diver lecturing another diver about potential failure points on their setup and how gear setup should be simple and uncomplicated to avoid confusion, and then immediately after, the diver giving the lecture strapped on a CCR, and moments after jumping in the water had to abort the dive due to an equipment malfunction.

I will stick to the octo on my primary reg set along with the 2nd stage on my pony bottle.

Dive how you want with the configuration that makes you comfortable. Be a thinking diver...you only need to justify your setup to yourself.

-Z

 

[txgoose]

yes you absolutely can. If the redundancy ultimately causes issues, in this case increased failure points and unnecessary added complexity to the system, then you have too much redundancy. This is why we don't have 2 second stages on any post in technical diving, why we don't have redundant SPG's, most people don't use dual bladder wings, etc etc. The added redundancy does not add any appreciable improvement to safety, but does in fact add unnecessary complexity. This is the foundation of hogarthian gear configurations and KISS

One thing that I wrote down in my recent solo class was Hick's law, paraphrased to: the more stimuli to choose from, the longer it takes the user to make a decision on which one to interact with. I think this goes along with part of what you're saying about keeping it simple.