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View Full Version : Rec Diver...When to Carry a Pony?



redsoxphan
11-09-2009, 17:45
So, I've seen a lot of threads on how to carry a pony & what size pony's different people carry, but I've not stumbled across a thread regarding when to carry one. I'm sure that there are MANY different opinions and/or personal preferences on this subject and I'm interested in hearing them.

Is there a certain depth that you'd never dive without one? Do you always carry one, regardless of the dive plan?

Keep in mind, I'm speaking solely in terms of rec diving.

navyhmc
11-09-2009, 18:56
The two times I carry a pony are when I'm solo diving (solo cert) and on deeper dives below 90' Then it's a slung 40.

scubadiver888
11-09-2009, 20:48
When to use a pony is different for different people. A few of the air hogs in my LDS will add a pony when we are diving the deep wrecks (100+ feet). When they are diving something shallow they'll leave the pony on the boat.

My instructor dives with a HP100 and she has a really low SAC (Surface Air Consumption) rate. I go through two AL80s in the time she uses her HP100. I've never seen her use a pony but she has a mounting bracket for one. So I assume there are times when even she will hang a pony (probably during wreck penetration).

If you know that you use 0.75 cu ft / min. at the surface then you know you'll use 1.5 cu ft / min at 33 feet, 2.25 cu ft / min at 66 feet, 3.0 cu ft / min at 99 feet, etc.

If your tank is an HP100 @ 3442 PSI then you have 100 cu ft. of air. So at 99 feet the tank will be empty at close to 33 minutes. You need to reserve air for getting to depth, safety stop at 15 feet, surface with 500 PSI means reserving (around 15 cu ft. of air). You also want to reserve some air for if there is an emergency (in cold water, if your buddy gets a free flow he'll need to hop on your octo. the two of you might have to make a control ascent, do a safety stop then surface).

For some people, bad on the boat with 500 PSI is fine. For others they will calculate the worst case scenario and make sure they have enough air for that plus a few under PSI as a reserve. If nothing goes wrong you might end up back on the boat with 1800 PSI. Calculating this way, 100 cu ft. of air doesn't last very long for a deep dive. So some people will sling a pony as well.

Another reason to sling a pony is as a redundant backup. As Navy has mentioned, when he is diving solo (not something I would do with my limited experience) he does not have the redundant backup of his buddy's octo so he'll sling a pony with a separate regulator.

You might want to google "rock bottom gas management".

Splitlip
11-09-2009, 22:04
I started slinging a 13 with a button gauge and short lp hosefor "solo" dives. I charge the reg then shut off the gas before I enter the water.13cf will take me up at normal pace with a deep stop and a safety stop.

As of late, I have gotten so used to it, I take it always. A dedicated hunting dive, I may think about a bracket that will allow me to reach the valve.

DMWiz
11-09-2009, 22:04
I don't have a hard and fast depth rule; although, I probably wouldn't do a dive below 80' w/o one. Usually my lack of familiarity with the site & dive partner dictates if I will be carrying a pony or not.

Splitlip
11-09-2009, 22:10
Here is the 13. So tiny, it almost looks out of place being slung.

JDC032.flv video by mm2002_bucket - Photobucket (http://s637.photobucket.com/albums/uu91/mm2002_bucket/?action=view&current=JDC032.flv)

CFDAlden
11-10-2009, 01:21
I always have my 19cf tank mounted. Personal piece of mind, I guess. :)

Tassie Diver
11-10-2009, 03:33
So, I've seen a lot of threads on how to carry a pony & what size pony's different people carry, but I've not stumbled across a thread regarding when to carry one.
Always carry a pony when you are about to run out of air:smiley2:

Q: Is a big pony a horse??

Tassie Diver
11-10-2009, 03:35
I started slinging a 13 with a button gauge and short lp hosefor "solo" dives. I charge the reg then shut off the gas before I enter the water.
Well done for charging the reg before entering the water. An additional good practice is to turn the valve on and off once you're at depth so the IP pressurises relative to the ambient pressure (not surface pressure). It will help prevent water flowing backwards through your reg.

Splitlip
11-10-2009, 06:02
I started slinging a 13 with a button gauge and short lp hosefor "solo" dives. I charge the reg then shut off the gas before I enter the water.
Well done for charging the reg before entering the water. An additional good practice is to turn the valve on and off once you're at depth so the IP pressurises relative to the ambient pressure (not surface pressure). It will help prevent water flowing backwards through your reg.
Thanks!

navyhmc
11-10-2009, 06:23
I started slinging a 13 with a button gauge and short lp hosefor "solo" dives. I charge the reg then shut off the gas before I enter the water.
Well done for charging the reg before entering the water. An additional good practice is to turn the valve on and off once you're at depth so the IP pressurises relative to the ambient pressure (not surface pressure). It will help prevent water flowing backwards through your reg.

Good advice Tassie!!!:smiley20:

jupitertreasures
11-10-2009, 07:14
The two times I carry a pony are when I'm solo diving (solo cert) and on deeper dives below 90' Then it's a slung 40.

Yeah...what he said.....:smiley20:

But I use a 13cf.

WD8CDH
11-10-2009, 07:59
I always carry a pony or some other source of redundant air if it is deeper than a pool. I also charge the regulator and leave it on during the dive. One less thing to fiddle with when I am confronted by a panicked OOA diver. The risk of an unnoticed leak is far less than the risk from time lost turning on the valve.

MSilvia
11-10-2009, 08:42
The two times I carry a pony are when I'm solo diving (solo cert) and on deeper dives below 90' Then it's a slung 40.
Ditto, although I don't actually have a certification for solo.

I'll also sometimes bring one along if I know I'm going to be buddied up with an unknown diver on a dive in the 60' to 90' range.

Grin
11-10-2009, 08:48
I use a 13 every dive no matter what. It's part of my settup and it would be more trouble to remove than it's worth. Once you get used to it, it's a zero issue. You don't know it's there anyway, if you backmount it like I do. I mount mine valve up. So it's right beside my main tank valve, aligned exactly the same, so verifying it's on at the same time the main tank is turned on is too easy / Stupidproof. With a little pressure gauge that is mounted so it's to easy to see, so I can verify tank pressure at the same time I turn on my main tank. I run it with the valve on during every dive for about 4 years now. Never had a issue once with doing it this way. I like it available, and easy, and too easy to verify / 100% idiotproof. Remember: The pony settup is worth a couple lbs also. So if you are properly weighted with your pony and you decide to leave it on the boat, you need to add some weight. Just dive the pony and keep it simple. If your turning it on to charge it, you might as well leave it on, is my theory. I have a crossfiller I use to top it off when neccessary also. That makes it easy to keep filled and not have to worry about taking it to the dive shop to it top off etc... (Stupidproof again).
I have a 19 I use, if I use the 13 during the day. Can't tell a difference between the two in the water. It's on your back and you don't know the difference between a pony there or nothing.
It's not like your a faster scuba diver without your pony :smiley29:. But most people leave them on the boat, and have all sorts of proceedures. Not me! I tryed alot of different configs and decided to simplify it to the max.
1. Get it out of your way(back mount). 2. Make it too easy to verify it's on and full. 3. Set up your gear to use it every dive and forrget-about-it.

navyhmc
11-10-2009, 09:11
I started out with a 13 cu, but then upped to a 19 after doing a test OOA at 60'. I was able to make it to the surface okay, but couldn't complete a safety stop. I know that the safety stop has been beat to death, but I personally like and do them. Given that, I switched to a 19 and anything below 60', it's good to go. Amazing what 6 cu ft will do at 20 feet.

For anything below 60', I use a 40 cu and find it works great. Even a switch at 130', a deep stop at 60 and safety at 20 I still had a few psi left.

Coaster
11-10-2009, 21:34
I carry a 19 all the time...so I am comfortable with the pony if I ever need to use it.

jbres1
11-10-2009, 21:52
I base the pony size on the depth I will be going to. Less than 30 ft. equals no pony. 30 to 60 ft its a 13, and below 60 its a 19.
I have a 30, but have yet to sling it on a dive.
I have not needed my pony, but have passed it off twice in the past 2 years to a buddy that ran low on gas. (they did a bad gas planning)
They would have blown the safety stop without my pony.

I like to look at my pony the same way I look at insurance, its better to have it and not need it rather than need it and not have it.

Jim Breslin

Grin
11-11-2009, 07:07
I use a 13 all the time to my almost exclusive depths of 60-80 ft. If I dive to 130 I should put the 19 on but I usually don't. I just realize that there will be no safety stop and I will be crunching on that enmergency accent if it ever happens. I have a 30 for the rare occassions I plan dives deeper than that. I wear my 13 even in 12 ft. Can't tell it's there, and I would have to add weight if I took it off, so what's the point.

navyhmc
11-11-2009, 08:39
Grin: I did a OOA test with a 13 at 120: With no deep stop, I was only able to make a 2 min safety stop at 15 before it was at 200 psi. My SAC for the dive was .48 cu ft/min. Might want to rethink at least the 19 for deep. It'll work, but there is IMO, no margin for error.

CompuDude
11-12-2009, 12:33
I always carry a pony or some other source of redundant air if it is deeper than a pool. I also charge the regulator and leave it on during the dive. One less thing to fiddle with when I am confronted by a panicked OOA diver. The risk of an unnoticed leak is far less than the risk from time lost turning on the valve.

I just don't get this line of thinking. How long does it take to turn on a tank? How long can you go without taking a breath, even in the worst-case scenario of a full exhale then nothing coming in? We're talking mere seconds.

Jack Hammer
11-12-2009, 14:55
I always carry a pony or some other source of redundant air if it is deeper than a pool. I also charge the regulator and leave it on during the dive. One less thing to fiddle with when I am confronted by a panicked OOA diver. The risk of an unnoticed leak is far less than the risk from time lost turning on the valve.

I just don't get this line of thinking. How long does it take to turn on a tank? How long can you go without taking a breath, even in the worst-case scenario of a full exhale then nothing coming in? We're talking mere seconds.
I'm with you on this, leaving a stage/pony/deco bottle's valve open the whole dive is, IMHO, just asking for it to be empty when you need it most. Murphy's Law has a funny way of occurring when least expected.

To the original question, it depends on who I'm diving with and what depth as to whether or not I carry a pony. When I do and I'm diving a singles configuration I prefer a 40, regardless of depth. I just like the way it slings vs the smaller sized cylinders better. After diving mostly doubles the past year, I feel kinda "nekkid" when I don't have a redundant gas supply with me.

Tassie Diver
11-12-2009, 15:17
I always carry a pony or some other source of redundant air if it is deeper than a pool. I also charge the regulator and leave it on during the dive. One less thing to fiddle with when I am confronted by a panicked OOA diver. The risk of an unnoticed leak is far less than the risk from time lost turning on the valve.

I just don't get this line of thinking. How long does it take to turn on a tank? How long can you go without taking a breath, even in the worst-case scenario of a full exhale then nothing coming in? We're talking mere seconds.
Good advice. Pressurise the reg at the bottom of the descent THEN TURN IT OFF.

It also leads to good practices if ever the diver progresses to multiple deco gases

navyhmc
11-12-2009, 15:28
I always carry a pony or some other source of redundant air if it is deeper than a pool. I also charge the regulator and leave it on during the dive. One less thing to fiddle with when I am confronted by a panicked OOA diver. The risk of an unnoticed leak is far less than the risk from time lost turning on the valve.

I just don't get this line of thinking. How long does it take to turn on a tank? How long can you go without taking a breath, even in the worst-case scenario of a full exhale then nothing coming in? We're talking mere seconds.

In all due respect WD8, I agree with Compudude on this. I will be honest, I usually don't turn on then off at depth, but will definitely add it to my dive plan. But IRT to turning the pony off, my immediate action drill for primary failure is to turn on the valve as I'm deploying the pony's reg. That's what I practice so I'm hoping in a real crisis, that's what I'll do. Not had to use it for real yet, so I can't say for sure.

Chilkie
11-15-2009, 21:02
Grin: I did a OOA test with a 13 at 120: With no deep stop, I was only able to make a 2 min safety stop at 15 before it was at 200 psi. My SAC for the dive was .48 cu ft/min. Might want to rethink at least the 19 for deep. It'll work, but there is IMO, no margin for error.


Heh, makes you wonder about those "spare air" gizmos and their true value....doesn't it????

IrishSquid
11-15-2009, 21:32
I'm not solo cert'd either but always dive with my slung 40. I sometimes end up solo when a couple of my buddies run low on air earlier in the dive. After escorting to the shore and am sure they are out and safe I continue my dive. My pony becomes my alternate air "buddy". I stay fairly shallow and nearby at this part of the dive. I feel kinda nekkid without it now.

WD8CDH
11-16-2009, 07:25
I always carry a pony or some other source of redundant air if it is deeper than a pool. I also charge the regulator and leave it on during the dive. One less thing to fiddle with when I am confronted by a panicked OOA diver. The risk of an unnoticed leak is far less than the risk from time lost turning on the valve.

I just don't get this line of thinking. How long does it take to turn on a tank? How long can you go without taking a breath, even in the worst-case scenario of a full exhale then nothing coming in? We're talking mere seconds.

This comes from over 35 years of diving experience. I have NEVER seen a pony become empty during a dive on it's own but I have been involved in and witnessed a number of panicked diver situations where it was next to impossible for the doner to get to the valve with the struggling OOA diver grabbing at everything.

Logic says that there is a remote possibility of losing air in your backup and Logic may dictate that it only takes a few seconds to open a valve, but panic seems to defy logic time and again.

You can practice by your self and you can practice with your buddy, but you can't practice with an unknown diver that is coming up at you like a freight train (maybe from behind with no warning).

You can't prepare for every possibility, but I know, at least with my equipment, a turned on pony is far more reliable than an unknown, panicked, diver's training.

BTW, Technical divers almost always keep air on both of their regulators with doubles.

navyhmc
11-16-2009, 09:29
True WD. And please don't take this as a flame, it's not meant to be and I only wish polite discussion.

With the tec divers that I have associated with, they turn off their stage bottles when not in use-for the reason of lost gas. Yes, they do have both regulators on withthe doubles, but both regs are literally right in front of them so they are immediately aware of gas loss.

As for the additional task load with a paniced OOA diver, the knob turn is in the plan...They want my reg, no prob, take it-I can get 7' away from them rather quickly. But in all likelihood, the paniced OOA diver is less of a probability than a failure of my reg and needing the pony.

But in truth, in my 35+ years of diving, I've had more reg issues (three) than OOA paniced divers. The closest I've come to a OOA incident is a buddy who was at 200 psi so we headed up and each of us was prepared to buddy breath the rest of the way. We didn't have to but it was planned.

Jack Hammer
11-16-2009, 12:19
I have far less than a decade of diving under my belt and I've seen pony's leaking air several times. To be clear, I'm not talking about a freeflow, I'm talking about occasional burping air from the reg as they go along. I don't think it would be enough to empty the bottle, but it does happen. I was taught to keep a stage/deco bottle charged and closed, then check it occasionally to make sure that it's still charged. This is to make sure that you have gas when you need it and help reduce the possibility of finding none to not enough deco gas. I treat a pony bottle the same way out of habit. Murphy loves divers and I prefer to limit his options to visit me.

Crimediver
11-16-2009, 17:15
Slung 19 when solo or deep.

CompuDude
11-17-2009, 13:34
BTW, Technical divers almost always keep air on both of their regulators with doubles.

Of course they do, that's their primary air source. Are you familiar with how manifolded doubles work? You don't "turn off" your octo, either, in a single tank scenario. Doubles doesn't change that.

Most, however, do NOT keep their air turned on on their slung deco bottles, however, which is a more accurate comparison.

thor
11-17-2009, 15:48
If you ever dive a NJ Wreck, most boats require a pony or doubles in the NE Atlantic, regardless of depth. Other than depth, current may also be a factor when deciding what dives to use a pony on.

WD8CDH
11-18-2009, 15:30
BTW, Technical divers almost always keep air on both of their regulators with doubles.

Of course they do, that's their primary air source. Are you familiar with how manifolded doubles work? You don't "turn off" your octo, either, in a single tank scenario. Doubles doesn't change that.

Most, however, do NOT keep their air turned on on their slung deco bottles, however, which is a more accurate comparison.

What I was saying, is they (we) don't turn off the valve on the manifold to the regulator (secondary) that we aren't using. And I don't turn off the valve to my pony (if that is my backup air source).

But I do turn off my valve on slung deco bottles because that is a planned, scheduled, gas change. Comparing a pony to a deco bottle is not an accurate comparison. The specific risk factors presented to a deco gas source are entirely different than the risk factors of emergency air sources so the operating procedures are different.

And yes, I do know how manifolded doubles work. I was diving with and building multiple outlet manifolds back in the early 70's when double outlet manifolds were not even commercially available.

RogerAg
11-18-2009, 17:02
I would like to dive with my 13 cu. ft. pony all the time but most of the dive boats don't like ponies attached to the tank like I do it. I Will rethink the sling.
I always fill my pony from anther tank so there are no refill charges. My wife gets great bottom time (2 hrs. when we let her) so I always top off my pony from her tank.
At this time my pony is back mounted upside down so that I can reach the valve, and the hoses don't seem to hang up like they do when mounted upright.
I never had to use my pony in an emergency but I have tested it underwater. Remember my tests were done while I was calm however here is the outcome.
At 80 feet 5 minutes.
At 70 feet 6 minutes.
At 60 feet 7 minutes.
At 50 feet 8 minutes.
At 40 feet 9 minutes.
At 30 feet 10 minutes.
At 20 feet 12 minutes.
At 15 feet 13 minutes.
This was a few years ago and I now get better bottom time, however a panicked diver might draw down the tank in just a few minutes, but its better then nothing.

StreetDoctor
12-09-2009, 00:39
Never.

kat
12-09-2009, 13:00
If I were diving solo (as a certified solo diver) I would make sure to have a pony with me. If not going solo, as long as I am comfortable with my buddy and his abilities if we needed to share air, I wouldn't bother.