Is a Pony Bottle too complicated for a beginner?

[lexvil]

I did not mention zero viz, as I would not dive in those conditions recreationally or with new divers. But, to answer your question, I use a primary light as my way of communication. Side to side sweeps would be the way I would communicate and OOG situation to my buddy. (Also what I teach my students)

Must have been something on another post I was reading, sorry, so on you hypothetical dive requiring 1500 psi in an 80, I would not even bother with such a dive and would call it with 3000 psi. Have you ever dove a place with crappy viz? I solo dive with other people because very often the viz sucks and getting separated happens often. There are many ways to dive and many varying conditions. You do, in you previous example make a good case for doubles.

 

[CT-Rich]

Prove me wrong, but please provide your calculations on how a pony bottle is better than, 1500 psi reserve for emergencies and a 23 minute bottom time at 80ft without unnecessary task loading and weight distribution on a new diver.

Basically, all that math for 80’ with a turn pressure of 1500 psi? Is the 23 minutes the expectation or the plan?

 

[Hartattack]

I believe this is a discussion. If you have a lot to say, feel free to make the post longer. I think once you hit the send button, all are free to respond (at least my understanding). I appreciate your posting an example dive plan.

Personally, I find planning like this overly complicated and prone to a lot of assumptions (which, to be fair is the point of planning). Most weekend putter around the reef diving won’t require this much detail and newbie divers will get lost/confused. Where I dive tides and currents are the great unknowns that can have a large effect on air consumption because a the direction and strength of the current can significantly change hour to hour.

Are you taking all that math in the water? Are you expecting OW certified divers to do that level of planning?

What you have in your example is a process for planning. What will this dive look like? What is the information that gets written on the slate and the diver needs to know and work around. When I am in the water, the only thing I care about is time, depth, direction, current pressure, turn pressure, NDL, temperature and direction of current and where am I exiting. There are a bunch of location specific details, but I am not doing any math if I can help it.

Great questions, and honestly, it's simple for the new diver, you plan the dive on land, and then your minimum gas is your minimum gas. That number stays constant after you plan it. So, if currents, waves, or surf diminish your SCR, then so be it. If we did my dive example and worked hard and only had 15 minutes of bottom time and then hit 1500psi, we have to go up as a team. It's an agreement and trust among the team that MG is MG; once hit, you thumb the dive.

 

[Hartattack]

Must have been something on another post I was reading, sorry, so on you hypothetical dive requiring 1500 psi in an 80, I would not even bother with such a dive and would call it with 3000 psi. Have you ever dove a place with crappy viz? I solo dive with other people because very often the viz sucks and getting separated happens often. There are many ways to dive and many varying conditions. You do, in you previous example make a good case for doubles.

I don't dive solo, but we plan the dive as a team with that knowledge beforehand in low viz conditions. However, we all dive primary canister lights that can cut through a lot of crap. Still, in the event of silt out or extremely low viz, we usually thumb the dive in recreational levels or have procedures for that, which is a bit above this pony bottle topic for now. But I would be happy to discuss them in another thread.

 

[CT-Rich]

Great questions, and honestly, it's simple for the new diver, you plan the dive on land, and then your minimum gas is your minimum gas. That number stays constant after you plan it. So, if currents, waves, or surf diminish your SCR, then so be it. If we did my dive example and worked hard and only had 15 minutes of bottom time and then hit 1500psi, we have to go up as a team. It's an agreement and trust among the team that MG is MG; once hit, you thumb the dive.

And back to the OP, you have an o-ring blowout at 1500 psi. Your dive buddy is out of your line of site (above, below, behind, silting out on the bottom). How much time can you devote to finding him? With a 20ft3 pony are you better off or worse off?

 

[Hartattack]

10m is STANDARD on most computers. It does not imply an emergency.
3m/min is non-STANDARD except in the deco world of GUE. This is a beginner forum, not a deco forum Get on topic.

Hint: once you've gone through all this off-topic stuff about min gas, I hope someone says...but what about a free-flow/seat-failure/blown hose/lost-buddy, etc.
The TOPIC is a pony bottle; it is for those things, NOT a replacement for having enough gas if nothing goes wrong.

Lots of CAPSLOCK, my guy. lol. MG is in case of an emergency—how have you missed this completely? I literally spelled it out for you with calculations. Once a diver in the team hits minimum gas, the dive is over. MG is there to get you and a buddy to the surface if a diver in the team has a catastrophic failure.

Now, lets say you want more bottom time, well, doubles is the answer (side or back mount) a pony bottle is unnecessary and a marketing gimmick by the dive industry.

 

[Hartattack]

And back to the OP, you have an o-ring blowout at 1500 psi. Your dive buddy is out of your line of site (above, below, behind, silting out on the bottom). How much time can you devote to finding him? With a 20ft3 pony are you better off or worse off?

Good question, and the times allotted in your MG calculations give you some wiggle room. But, there is always room for separation and bad days. So, with that said, you have already calculated your MG for the team, so you know, you have more gas than 1500 psi in our example, and you are at max 80ft. How long would it take you for a direct ascent to the surface at that depth if you couldn't reach your buddy?

Caveat: We dive as a team in formations and close to each other, with powerful primary lights for communication, but I know other divers do not do this so to each their own, but that is my "dogma" I follow when I dive.

 

[lexvil]

I don't dive solo, but we plan the dive as a team with that knowledge beforehand in low viz conditions. However, we all dive primary canister lights that can cut through a lot of crap. Still, in the event of silt out or extremely low viz, we usually thumb the dive in recreational levels or have procedures for that, which is a bit above this pony bottle topic for now. But I would be happy to discuss them in another thread.

Dealing with bad viz is off topic unless it’s one of the reasons to carry a little extra air. When the algae bloom is bad light can limit you ability to see more than help, easy to lose your buddy in Monterey and calling the dive is often called for,having the pony clipped to you or not won’t change any of these things but can be useful in some instances. It’s just another way to dive.

 

[Hartattack]

Dealing with bad viz is off topic unless it’s one of the reasons to carry a little extra air. When the algae bloom is bad light can limit you ability to see more than help, easy to lose your buddy in Monterey and calling the dive is often called for,having the pony clipped to you or not won’t change any of these things but can be useful in some instances. It’s just another way to dive.

Yeah, if that makes sense for you guys/gals over there—more power to you. I'd be in doubles, lol. But, if I had to make it a rec/single AL80 dive, I'd thumb it if viz got bad, IMHO. I can always dive another day.

 

[tursiops]

Lots of CAPSLOCK, my guy. lol.

You appear to skip things said, otherwise.

MG is in case of an emergency—how have you missed this completely? I literally spelled it out for you with calculations. Once a diver in the team hits minimum gas, the dive is over. MG is there to get you and a buddy to the surface if a diver in the team has a catastrophic failure.

So now it is an emergency, but you are going to ascend at 3m/min? Right.

Now, lets say you want more bottom time, well, doubles is the answer (side or back mount) a pony bottle is unnecessary and a marketing gimmick by the dive industry.

Pony bottles are not for extending bottom time; you keep saying that, but no one else is. You even asked why they aren't part of the gas plan; the reason is they are not part of your plan. They are a redundant gas source, for an emergency. An emergency like no buddy. [Mod edit]