Pony practice...what do you do??

[kanonfodr]

Appreciate the responses so far. A little more info on the setup I am running: I dive a hog rig (ss bp/w, long hose reg setup) and my backgas is usually an LP95 tank. My pony is an AL40 and I carry it slung on my left side with the 2nd stage tucked underneath the hose, between the tank and my body, and a 2" spg on a 6" HP hose ziptied to the 1st stage where it can face me and be easily visible. I'm going to organize my responses to individual posters below:

Burna: You are correct in that a pony isn't there to correct for poor gas management, but occasionally we slip up or the swim back is a little longer or we're stressed for some reason and using air faster on the return. I figured it would be safer to leave around 700 psi in my backgas (RB for 60' according to my math) and then switch to pony so I still have air to respond to a buddy's problem and donate to them. As far as keeping the pony's valve on...that is a good way to drain your bailout and I'd rather have an Oh Crap moment and have to take a few seconds to get air vs. not having any air/reduced air in my bailout.

wedivebc: Good point. But then, if I plan to use my pony as stage, I run the risk of not having enough bailout. The only way around this I see is to only breathe it down by about 500-1000 psi, then turn it off, but if something really stupid happens I might really miss those extra 6 or 12 cu ft of air.

dumpsterDiver: Makes sense, it's one less step to ensure both divers are still breathing.

GrumpyOldGuy: I hear you, if a situation forces me to go to pony, I am going to be doing some serious self-reflection as well. I also like how you do your ascents from a moderate depths to gauge how much air you really use. Good info to know, IMO.

Atomic Diver: I'm not quite ready for doubles yet, still need to get myself good in singles. But I wouldn't mind eventually jumping over to the doubles side.

Peace,
Greg

 

[tomfcrist]

Plan Dives, and use a "H" or "Y" type Valve, better yet dive doubles, then there is no need for a pony, if you properly plan a dive, and watch your spg, you should be ok.....

Should is a fairly scary word when I'm diving.

What if you are diving doubles and have a catostrophic manifold failure? I know its not probable, but just humor me. and lets assume you are still 150 ft down. Would you like the added insurance of a pony at that point?

 

[tomfcrist]

To the OP, I back mount and have the bottle constantly on. I store the reg just like my octo but on my left side. I do alot of pool work, and since im there anyway, i practice just as regularly as i do with my octo.

 

[shoredivr]

Why do you keep advising H or Y valves? These are just about obsolete in most situations

GOG , when the water temperature is 36F up here like it is now, I like having an H-valve on my single tanks, that way if there's a freeflow due to the cold water, I can shut down that reg, and switch to the other reg.

 

[Atomic_Diver]

tomfcrist- at 150' with a "catastrophic manifold failure" (as in compleatly torn off?), i would most likely signal my buddy, and reach for his 7' primary hose as he switched to his shorter length hose, then make an accent towards my next deco ceiling (if one exsisted), if for gods sake my buddy could not be found, i would do (some form) of an Emergancy accent towards the shallowest depth i could safely breath from my deco bottle(s) since most likely if someone is diving at 150' its a deco dive, so there for they would be carrying such.....

 

[GrumpyOldGuy]

GrumpyOldGuy: .... I also like how you do your ascents from a moderate depths to gauge how much air you really use. Good info to know, IMO.

My practice ascents are done from 75'. At this depth I feel safe to omit the deep stop I would normally use for deeper dives.

I use several variations, depending on location and buddy. It can be as simple as switching to the pony doing a 30FPM ascent to 15', followed by a 3 minutes safety stop. Since I cannot see the button gauge, I switch to back gas after the S/S and spend another 5 minutes shallow just to compensate for the missing deep stop. After the dive, I note the total air used in the pony, which is typically 4 cu ft. In a real emergency, I am sure it would be more, probably double.

 

[DCBC]

When I used a pony, it was for a catastrophic failure only. You never considered pony gas into your gas management plan (which was the original concept of the pony bottle to begin with). Don't confuse this with separate cylinders to supply different mixtures, a traveler or decompression gas.

I'm with GrumpyOldGuy on the free ascent (CESA) practice. I do CESA for OW students (65' and Advanced students at 115' (to the safety stop). In the Navy we use to practice doff and don of SCUBA at 100' (that's a real experience; swimming down from the surface holding your breath and looking for the strobe on your tank).

 

[GrumpyOldGuy]

GOG , when the water temperature is 36F up here like it is now, I like having an H-valve on my single tanks, that way if there's a freeflow due to the cold water, I can shut down that reg, and switch to the other reg.

Hence, my comment "most situations". Below 45F you are in your own special world. For the rest of us, H or Y valves are very rare.

I agree, in real cold water, diving 2 1st stages is a big bonus. If you have to share air, the volume of 2 divers on 2nd stages in a single 1st stage increases your change of free flowing substantially. Here, a H valve is almost as nice as doubles.

As for a random free flow, the advantage of the H valve is not clear over a properly sized pony. Yes, you may have more gas initially, but shutting down the offending regulator takes time since it is placed close to your center (unlike double where the vale is well to the side). If you can't reach the valve or you are too slow you may loose all you gas. You still have to switch 2nds. It is very skill dependent. It is a tool, it may be a good fit for some, but in the end, it is not the same as a totally redundant air supply.

The pony on the other hand only requires you to put the 2nd in your mouth. Simple, but not idiot proof.

 

[burna]

If you dive with it charged and off, don't count on having a breath or 2 in the hoses. Jumping in you can loose the line pressure in a second and never be aware. You only have one hose holding air, not 2 or 3 like a standard regulator. Again, you options are limited by how you carry it.

Which is why I recharge it once in the water and occassionally during the dive. Still no guarantee tho'.

For me (back mount, modest size with a button gauge), the only viable strategy is to head for 20' at 30FPM. Then wait out the safety stop, constantly monitoring to make sure I don't go OOG a 2nd time. The size is not viable to troubleshoot any problems and is a practical trade off for traveling, not the ideal size. Others may dive with larger pony bottles and have more options.

This doesn't make any sense to me at all.

What's the point of a button gauge if you have the thing back mounted? How can you be "constantly monitoring to make sure I don't go OOG a 2nd time." ?
If you had a gauge you could read or had it stage rigged, then there would be no reason to worry about running out of air during the ascent.

The pony should be of sufficient size to allow you to conduct a normal ascent including all stops (deep if you want them) otherwise it is too small.

Burna: You are correct in that a pony isn't there to correct for poor gas management, but occasionally we slip up or the swim back is a little longer or we're stressed for some reason and using air faster on the return. I figured it would be safer to leave around 700 psi in my backgas (RB for 60' according to my math) and then switch to pony so I still have air to respond to a buddy's problem and donate to them.

I don't agree with the amount of gas you're talking about for ascent (you should have enough back gas for both you and your buddy), but yeah, I guess in theory I agree. I personally wouldn't do it that way tho'.

If you have a 40cuft, then you could use that in your plan (i.e a stage bottle rather than pony) whereas mine is only a 19cuft which, although it is enough for me to do a complete ascent with all stops, it really is only a bail out bottle IFAIC.

As far as keeping the pony's valve on...that is a good way to drain your bailout and I'd rather have an Oh Crap moment and have to take a few seconds to get air vs. not having any air/reduced air in my bailout.

Yep, and I went on to say exactly that.

How people choose to use their equipment is entirely up to them, I not going to say anyone is 'wrong', just that I wouldn't do it that way.

 

[kanonfodr]

<snip>

I don't agree with the amount of gas you're talking about for ascent (you should have enough back gas for both you and your buddy), but yeah, I guess in theory I agree. I personally wouldn't do it that way tho'.

For a 60' ft ascent I estimated that two divers will use approx. 14 cu ft of gas, including a 30', 20' and 10' stop. With a tank factor of 3.5, that means I need about 500 psi in my tank to get us both back safely, but that means breathing the tank dry so I add a few hundred PSI to give some wiggle room and also for inflating the wing when topside.

How people choose to use their equipment is entirely up to them, I not going to say anyone is 'wrong', just that I wouldn't do it that way.

^^^^^^^^^^^^Werd

Peace,
Greg