What pony size?

[redacted]

Well said!! However I am a huge advocate of every diver waking up to the notion of being 100% selfsuficient. Correct, a well planned dive should not require a pony, shall we remove car airbags if we plan our drive? Variables are something we plan to avoid but arise in every sport. Deciding how big your safety net needs to be is of personal preferance based on 'what, where, how', how much air do you need to survive an absolute worst case scenario? That number is as different as a fingerprint. I feel good intent, lazy execution.

I do not carry a pony to compensate for a planning failure on my part. I carry a pony in case of an equipment failure effecting my primary gas supply. My primary gas supply is sized to meet the requirements of my planned dive including reasonable contingencies.

 

[DevonDiver]

Why is nobody talking about Spare Air? Isn't that supposed to happen?

 

[Wookie]

As for your "go back and learn how to dive" comment....no but you could use a refresher course in social skills

He said he knew it would sound snooty but didn't mean it that way. And I took his "you" to not necessarily mean directly personal to the OP but to anyone that thought that way, and I'd tend to agree with that sentiment.

The OP is right, I have no social skills. Comes with rescuing too many divers who got in trouble because they don't know what they don't know, and having to balance between "I know you are on vacation and are paying for a good time" and "You Idiot!! Do you have any idea what you just did?!?!?! Do you know how many people I've seen die because of what you just did?

What I wish I'd said was...

I do not carry a pony to compensate for a planning failure on my part. I carry a pony in case of an equipment failure effecting my primary gas supply. My primary gas supply is sized to meet the requirements of my planned dive including reasonable contingencies.

But I have no social skills. I'm sorry for offending the OP.

---------- Post added August 11th, 2013 at 10:54 AM ----------

Why is nobody talking about Spare Air? Isn't that supposed to happen?

Only in your dreams, Andy. That's where Spare Airs go.

 

[waterpirate]

Although I agree with many points on your post, this part is weak logic for a couple of reasons,
1) You are only looking a divers used their pony in an emergency, that should be close to zero unless you dive with a bunch of bozo's, in which case their opinion is worthless.
2) Your are ignoring the divers who have a pony, but left it topside because is was too big / cumbersome, they will NEVER report anything about using the pony in an emergency.

Sarcasm and an ancedote should be applied, but since you brought it up, I will address it.

1. How about the standard single tank rig, primary and octo, that has a 1st stage o-ring failure or worse? Not a bozo, just lucky.

2. Any diver who has chosen to get a pony and leaves it topside because it is cumbersome or hard to carry has suffered from a breakdown in logic.

3. The elaphant in the room that everyone is ignoreing is that on the internet everything is no biggie. Includeing no good way to measure your SAC when you are truly distressed. On a recent forray to my max depth I encountered a issue and did a rapid ascent to 130fsw and got on my 40 of 28/20. I sorted myself out, prepared to ascend and checked my spg. I was amazed how little gas was left to get me to my next stop. Moral of the story is that when stressed you can never have the amount of gas that you think it is going to take to get you out slow and safe.
Eric

 

[String]

Been thinking for a while about a redundant air source. I'm thinking either 19 or 30cu ft. What are advantages (other than less/more air) disadvanatges if any?

To be blunt, if you're asking this question then you aren't really experienced or trained enough to use one safely.

A pony is a gas source for emergencies. It needs gas planning to know its limits and those limits are different for every person.

Work out your SAC rate then run the figures for the different size tanks to see what depth one will get you out safely from. It's the only method of determining the size required and the limitations.

I see far far too many people just slapping a pony on and doing dives where if they needed it had no chance in hell of it getting them to the surface simply because they haven't done any planning.

So, id say before thinking of a pony size learn gas management and THEN you can work it out using figures applicable to you.

 

[Michael Guerrero]

I carry a 30 cu ft pony bottle side slung, but I would recommend a 40 cu ft. First, it should be plenty of gas for recreational contingencies as a backup air source, or if you accidentally go into deco. Second, if you decide to do decompression diving, the standard is 40 cu ft for rich deco gas, so you could just get it O2 cleaned and use it for that purpose. You can use a 30 cu ft also, but 40 is more common.

I also recommend the side-slung method vs. back mounted so you can see the pressure gauge, fit on dive boats, reach the valve easily, and pass it off if needed to an OOA buddy.

 

[GrumpyOldGuy]

Sarcasm and an ancedote should be applied, but since you brought it up, I will address it.

1. How about the standard single tank rig, primary and octo, that has a 1st stage o-ring failure or worse? Not a bozo, just lucky.

2. Any diver who has chosen to get a pony and leaves it topside because it is cumbersome or hard to carry has suffered from a breakdown in logic.

3. The elaphant in the room that everyone is ignoreing is that on the internet everything is no biggie. Includeing no good way to measure your SAC when you are truly distressed. On a recent forray to my max depth I encountered a issue and did a rapid ascent to 130fsw and got on my 40 of 28/20. I sorted myself out, prepared to ascend and checked my spg. I was amazed how little gas was left to get me to my next stop. Moral of the story is that when stressed you can never have the amount of gas that you think it is going to take to get you out slow and safe.
Eric

1. I took a shot at you repeating the old adage "no one every complained about having too big a pony when the needed it". Not the need for a pony. Things like o-ring blowing, freeze ups (most likely in my case) or SPG getting stuck are all valid reasons for carrying one. Repeating that old line added nothing.

2. It is a realistic problem and not just a lazy diver. Many divers travel and transporting larger pony's becomes problematic. We all make choices about how much safety gear to carry based on a trade off of size vs. utilization. Ultimately on these threads we hear a progressing of sizes up to sling an 80 or go to doubles for ultimate safety. In some regards it correct, just not practical for many.

3. True. This is the reason I dive the blue hole (a local spring, boring but 84' deep) every 4-5 weeks regardless of weather. I drill myself silly, deploy my pony and ascend. When I have one of my sons along, we stress each other. Shooting an SMB while on the pony and not using the primary or ascending without mask or plain old sharing air or buddy breathing. It is remarkable how after routinely practicing the emergency procedures that our SAC rates stay reasonable. Drill baby drill!

 

[oldschoolto]

Hanging a aluminum 80 at 15/20 feet is a really good way to be ready for out of air or to do a unplanned deco ..

Jim..

 

[redacted]

I carry a 30 cu ft pony bottle side slung, but I would recommend a 40 cu ft. First, it should be plenty of gas for recreational contingencies as a backup air source, or if you accidentally go into deco. Second, if you decide to do decompression diving, the standard is 40 cu ft for rich deco gas, so you could just get it O2 cleaned and use it for that purpose. You can use a 30 cu ft also, but 40 is more common. .

Some dive ops may restrict the size pony you are permitted to use. The one at the FGB will permit a 30 but not a 40.

 

[String]

Hanging a aluminum 80 at 15/20 feet is a really good way to be ready for out of air or to do a unplanned deco ..

Jim..

Great in theory...but it assumes you can make it back to the hang tank with whatever problem occurred. Which is not always possible.