AL40 for redundancy diving single tank on deeper dives.

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No, he recommended against any wing bigger than 45#, unless you could show the calculations justifying it. He was strongly in favor of redundant lift, tho.

In general he laid out his views of the pros and cons of pretty much every suggestion he made, and made it clear whenever his personal choice deviated from "mainstream" opinions. He never said "don't use a long hose in a wreck." He explained why it wasn't his preference for wreck penetration, and why it might make sense in other scenarios. My fellow student had a long hose for the first day or two, then dove a few days with a shorter hose. I'm not sure what he'll choose in the long run.

I appreciated the approach that exposed us to differing views, gave a solid base in the reasoning, and encouraged to to try different equipment configs as we developed. FWIW, the instructor is an extremely experienced tech diver.

I won't engage in an argument, nor try to "defend" another's views. I do listen and try to learn from the widely differing views from other divers, both here and in RL.
Happy diving!
Don
 
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Hi Stuart, I think I qualified later in my post that we have the same gas capacity as pony divers with regard to preventing going OOA, but not the same redundancy of equipment n the event of failure.. We rely on our buddy system for redundant equipment in the event of equipment failure, and the buddy's bigger tank for gas to surface. Personally, we don't want extra weight, extra bulk, extra complexity, reduced streamlining, and extra stuff to manipulate, which is why I have so far resisted a pony, when I can get the same benefit with good buddy practice and a little bigger tank.

I think you're not doing anything special. Everybody should have enough gas at every time during the dive to share with his/her buddy who is suddenly OOA and make a safe ascent. This is not another perspective but just basics. Renting bigger tanks for deeper dives is common sense.

It seems that you think losing your buddy is always due to bad buddy practice, but it isn't. When you dive in really poor viz, losing your buddy is not unusual, especially in situations when one diver is in trouble, or in currents. I think pony bottles are more popular with cold water dives in poor viz than for crystal clear warm water.
 
No, he recommended against any wing bigger than 45#, unless you could show the calculations justifying it. He was strongly in favor of redundant lift, tho.

In general he laid out his views of the pros and cons of pretty much every suggestion he made, and made it clear whenever his personal choice deviated from "mainstream" opinions. He never said "don't use a long hose in a wreck." He explained why it wasn't his preference for wreck penetration, and why it might make sense in other scenarios. My fellow student had a long hose for the first day or two, then dove a few days with a shorter hose. I'm not sure what he'll choose in the long run.

I appreciated the approach that exposed us to differing views, gave a solid base in the reasoning, and encouraged to to try different equipment configs as we developed. FWIW, the instructor is an extremely experienced tech diver.

I won't engage in an argument, nor try to "defend" another's views. I do listen and try to learn from the widely differing views from other divers, both here and in RL.
Happy diving!
Don
So why was that? And what's his procedure should you need to donate to your buddy in an overhead when you have to swim out single file? Break the doubles down before coming out? Your buddy has a catastrophic failure of a tank or manifold. He loses much of his gas getting things shut down to preserve as much as possible. You are too far in for him to swim out on his remaining supply. How are you sharing air to get out through tight passages?
 
So why was that? And what's his procedure should you need to donate to your buddy in an overhead when you have to swim out single file? Break the doubles down before coming out? Your buddy has a catastrophic failure of a tank or manifold. He loses much of his gas getting things shut down to preserve as much as possible. You are too far in for him to swim out on his remaining supply. How are you sharing air to get out through tight passages?

Let me guess his answer: every diver in such a wreck must be self-reliant and bring his own truly independent redundant air supply, like for a solo dive. If one diver is suddenly OOA, the team must be able to get out of the wreck without air sharing between divers.

This is not an argument for or against the long hose. It just acknowledges that in very restricted environments air sharing between divers is so difficult, no matter how long the hose, that it can't be your one and only method of handling an OOA situation.
 
So is the old adage "rich is right" out dated or never really true?
Different agencies with different philosophies.
 
Let me guess his answer: every diver in such a wreck must be self-reliant and bring his own truly independent redundant air supply, like for a solo dive. If one diver is suddenly OOA, the team must be able to get out of the wreck without air sharing between divers.

This is not an argument for or against the long hose. It just acknowledges that in very restricted environments air sharing between divers is so difficult, no matter how long the hose, that it can't be your one and only method of handling an OOA situation.
Yes, that's the gist of it. And he did not argue against long hoses in general, but that redundancy and self-reliance are particularly critical when penetrating wrecks. And that a long hose was one more potential point to get hung up on a pointy bit of a wreck (of which we saw plenty.) I did try to imagine sharing a 7ft hose through narrow bulkheads, up/down stairs designed for one person at a time, and such; it wasn't a reassuring mental picture.

So is the old adage "rich is right" out dated or never really true?
Old adage or not, he did say he uses "right for rich", but suggested we carry the bottle wherever we felt most comfortable. (we normally only had one side bottle, except when I was slinging contingency gas.) We always confirmed switches with a buddy (both reading the tank, following the regulator hose, and confirming the computer was switched to the proper gas.) If not carrying a long hose or can light, I don't see that it matters which side the gas is carried on. And yes, the instructor advised against can lights given the current state of LED lights (bring a primary, backup, and backup to the backup.) He's also very big on strobes for marking waypoints in the wreck.

I really don't want to be in the middle of a fire-fight over "best practices" in the context of a specific course. I understand his rationales, but wouldn't do the instructor justice by trying to speak for him.
 
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And that a long hose was one more potential point to get hung up on a pointy bit of a wreck (of which we saw plenty.)
I hooked my big, loopy conventional hose a number of times in wrecks before switching to the long hose, which sits tight to the body.
 
So is the old adage "rich is right" out dated or never really true?
For OC backmount, "right rich lean left" is pretty dated (like 10+ yrs out of date). Has killed a number of divers too. I'm sure you can find some instructors teaching it but you can find at least one instructor teaching just about anything. Mainstream has become: BP/W, long hose on right post, stages marked with their MOD and confirmed via their MOD (not different regs etc) and on the left. Hence the near overwhelming consensus here to sling the AL30 or 40 pony "like a stage" and on the left so the hose routes behind the neck when deployed.
 
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