Tried to Kill Myself but Failed!

[BlueTrin]

I guess that wouldn't work if you can't reach it because it's backmounted...

That makes sense now, I didn’t realise that at first.

Is the advantage of back mounting a pony that it is not in the way of the front area?

Myself, I guess I would sling it just out of habit, but I was curious about the advantages of backmounting: I imagine it also put less strain on the shoulder when walking in addition to keep the front clear.

 

[OTF]

re: not running a pony SPG - I think that's crazy. I need to know how much air is in my pony before, during, and after the dive. SPGs are not a significant failure point in my opinion. Not knowing my gas is a significant potential failure point.

My pony regs are set up exactly as a deco stage would be. In fact I use the regs for both purposes.

I think there are a LOT of reasons to sling like this instead of backmount. It's much harder to take the wrong reg as occurred in this thread, it's possible to don/doff/stage at the waters edge/pass to another diver if needed, you can more easily operate the valve and see the SPG, it's more streamlined and less likely to entangle, much easier to disentangle if necessary, accepts basically any bottle size, and uses the same setup and practiced muscle memory as deco bottles. There are good reasons that this is evolved as the standard setup for tech diving and I don't get why so many rec solo divers backmount their ponies like it's 1990. But there are multiple extremely long threads about that, and this doesn't need to become one.

 

[NYCrecdiver]

Thanks for posting your experience for all to learn from! It's a confirmation for me that having AI transmitters on both my primary cylinder and pony is a good thing. Separate SPG for a pony wouldn't be checked normally and by the time I'd notice my primary air is not reducing, it'd be too late as I've already used up too much pony air and need to abort the dive.

 

[RobPNW]

It seems in any risky activity, there's a sweet spot between being in danger because you don't know enough to know how much you don't know, and being in danger because you know a lot (and may get complacent). I know enough, to know how much I don't know

 

[VikingDives]

re: not running a pony SPG - I think that's crazy. I need to know how much air is in my pony before, during, and after the dive. SPGs are not a significant failure point in my opinion. Not knowing my gas is a significant potential failure point.

Before the dive - I agree.
During the dive - Why? it's still the same amount as you had before the dive. Unless it fails, in which case the dive is over.
After the dive - Why? If you're using the pony as a pony and not additional breathing gas, it should not have significantly changed...

A solo diver should know their gas consumption rate. I know I can spend about two hours on a pony at 10-15 feet. Add in the time it takes me to get to 10 feet from depth, and factor in stress and maybe we're down to an hour of use before I run out of air.

Why would I need to know my pressure?

To put it another way, a properly used pony is in a binary state. It either has air for me underwater, or it does not. If it has air, I'm going to use it. If it does not, I'm going to the surface. A pre-dive check will tell me if I have air, and I'm keeping my pony off during the dive, so if I need it, I will have air. I don't need an spg to tell me that.

If I transition to my pony, my dive is over. That air needs to get me to a safety stop, and hopefully keep me there for three minutes... If for some reason it fails to provide me with the necessary gas, I'm right back to an emergency swimming ascent. An spg is meaningless here.

If I did something unusual as a solo diver and I went into deco and ran out of back gas during my ascent or stop, I'd transition to my pony and I'd do as much deco as possible. If gas runs out on the pony, I'm going to the surface. An spg is meaningless again.

My pony is like a reserve parachute. If my primary parachute fails, I need my reserve to get me to the ground. I don't need to know how fast I'm descending, I just need to not be dead when I get there.

Scuba gear is incredibly reliable, but those tiny o-rings in your spg are, in my experience, the most failure prone bit of gear the average diver carries. You said you think they aren't a significant failure point, but they are a failure point.

Eliminating any failure point in a backup system seems like a good idea to me, but I'm open to new ideas. Why is not having an spg crazy?

To be fair, I have used my sidemount short hose with an spg on it, on my pony, in the past. It's all about the risk you're willing to accept, but if you have a dedicated solo system I think it makes more sense to eliminate the spg.

If you're swapping between a pony and deco, I'm not fundamentally opposed to an spg, but there is risk involved in the decision. I wouldn't accept the risk that @NW Dive Dawg does. I'd want a fully redundant system (sidemount).

About the only time I use a pony bottle is when I teach, and it's to cover me in the event of an equipment failure. I don't want to have to share air with a student while bringing more than one student to the surface, especially on their first couple of dives.

 

[Nemrod]

Good job on not panicking, congrats on failing that attempt

I was wondering if a pony could be rigged like a stage where you put rubber bands on the cylinder and fold the hose inside the bands, the reg would just sit there?

Yes:





I sling my buddy bottle left side and generally bundle the hose and second stage.

 

[johndiver999]

Not to derail this topic, but as a newer diver who's starting to use a pony for deeper rec dives (not solo but as an extra safety measure), I'm curious about people's thoughts on ditching the pony SPG.

I've use a small 1" button SPG directly attached to my slung pony's 1st stage for the following reasons:
1. I can check the tank pressure before the dive to make sure my pony is still full.
2. I can check the tank pressure during the dive to make sure it's not leaking.
3. If I have to switch to the pony and begin ascending, I can monitor my gas to make sure I have enough to perform the 3 minute safety stop. (Please don't let this get into a debate about pony bottle size).

What do other people think/do?

*NOTE* If mods think this should be moved out of the Basic Scuba forum, please do so.

I think the advice to ditch the spg (and the long spg hose) was for the back mounted pony, but I'm not really sure.

As for your configuration, it would be ridiculous to not have a pressure gauge on your slung pony. I have used the button gages for years and they are reasonably robust and have less failure points than a spg with a hose and a spool and those additional O-rings.

I have a button gage on my back mounted pony, so while I am diving, I never really know if the air has leaked out or not. That is one reason why I feel it is so important to use a necklace, so that you are more likely to feel a free flow of the second stage.

 

[johndiver999]

Before the dive - I agree.
During the dive - Why? it's still the same amount as you had before the dive. Unless it fails, in which case the dive is over.
After the dive - Why? If you're using the pony as a pony and not additional breathing gas, it should not have significantly changed...

A solo diver should know their gas consumption rate. I know I can spend about two hours on a pony at 10-15 feet. Add in the time it takes me to get to 10 feet from depth, and factor in stress and maybe we're down to an hour of use before I run out of air.

Why would I need to know my pressure?

To put it another way, a properly used pony is in a binary state. It either has air for me underwater, or it does not. If it has air, I'm going to use it. If it does not, I'm going to the surface. A pre-dive check will tell me if I have air, and I'm keeping my pony off during the dive, so if I need it, I will have air. I don't need an spg to tell me that.

If I transition to my pony, my dive is over. That air needs to get me to a safety stop, and hopefully keep me there for three minutes... If for some reason it fails to provide me with the necessary gas, I'm right back to an emergency swimming ascent. An spg is meaningless here.

If I did something unusual as a solo diver and I went into deco and ran out of back gas during my ascent or stop, I'd transition to my pony and I'd do as much deco as possible. If gas runs out on the pony, I'm going to the surface. An spg is meaningless again.

My pony is like a reserve parachute. If my primary parachute fails, I need my reserve to get me to the ground. I don't need to know how fast I'm descending, I just need to not be dead when I get there.

Scuba gear is incredibly reliable, but those tiny o-rings in your spg are, in my experience, the most failure prone bit of gear the average diver carries. You said you think they aren't a significant failure point, but they are a failure point.

Eliminating any failure point in a backup system seems like a good idea to me, but I'm open to new ideas. Why is not having an spg crazy?

To be fair, I have used my sidemount short hose with an spg on it, on my pony, in the past. It's all about the risk you're willing to accept, but if you have a dedicated solo system I think it makes more sense to eliminate the spg.

If you're swapping between a pony and deco, I'm not fundamentally opposed to an spg, but there is risk involved in the decision. I wouldn't accept the risk that @NW Dive Dawg does. I'd want a fully redundant system (sidemount).

About the only time I use a pony bottle is when I teach, and it's to cover me in the event of an equipment failure. I don't want to have to share air with a student while bringing more than one student to the surface, especially on their first couple of dives.

This sounds like someone who has never HAD to use a pony to make it to the surface. When the SHTF it is nice to know what is in your pony.

Still I can't read the pressure on my back mounted pony, but in a real emergency it WOULD BE nice to be reassured that your assumed back up supply is actually there. So people who back mount and run an spg on a hose, will most likely be a lot more relaxed on an emergency ascent than someone who is just hoping/ guessing about the pressure in the pony. I'm not sure it is a reasonable trade off, but I sure DO understand why someone might choose to dive with a spg and hose on their back mounted pony (even though I don't).

If I did something unusual as a solo diver and I went into deco and ran out of back gas during my ascent or stop, I'd transition to my pony and I'd do as much deco as possible. If gas runs out on the pony, I'm going to the surface. An spg is meaningless again.

As for the bolded comment, that again sounds like someone who has not really dived through the scenario they are describing. Why, because that is NOT the way to do it, when diving with a pony that has unknown pressure in it.

If you have a back mounted pony and lets say you have no way to check the pressure in the pony and you "run out" of air on the bottom - meaning breath the main tank down to where it is hard to inhale. You do NOT want to ascend with that main tank and switch to the pony only when the primary runs out! That would be very short sighted. What you want to do is, immediately switch to the pony. You want to preserve whatever air is in the main tank for worst case scenario, you also want the main tank air to add air to the bc for a non swimming, buoyant ascent.

So to be more explicit, lets say you are at 100 feet, alone and screw up and it gets hard to breathe. You switch immediately to the pony, and now you know it at least works and was turned on. You can then press the up button on the inflator (a little) and start a passive resting ascent that will minimize your air consumption. When you make it up to safety stop depth, THEN you can switch back to the main tank, extend your stop and breath down the main tank as low as you wish. There will be probably 2 minutes of air for the safety stop if you are calm and you have been motionless for the last few minutes. You can finish up with the pony after that, but when it runs out there is zero warning... better to happen at 15 ft.


But what if you just head up with the very nearly empty tank, make it to 50 or 70 feet when it stops delivering meaningful air and then you switch to the pony and find that it is empty, drained, failing to work or you forgot to turn it on? Now you really ARE F-ed. This is what you want to avoid.

In short if you are diving with a pony with unconfirmable air supply, get onto it immediately, don't wait to find out how screwed you really are. In my mind this is a very important distinction.

 

[NYCrecdiver]

Why wouldn't someone want to know what's inside their potentially life-saving pony during the dive? All this worry about an "additional point of failure" makes me chuckle. At least you'll know there's a failure!​

 

[johndiver999]

Why wouldn't someone want to know what's inside their potentially life-saving pony during the dive? All this worry about an "additional point of failure" makes me chuckle. At least you'll know there's a failure!​

Why do you laugh about a potential failure point? If you do a thousand dives with your rig, there is a reasonable chance that during one or two of those dives, the more complex component of the pony bottle rig will experience a failure, problem or leak. Plus it is extra cost and maintenance. However, if you are careful and lucky during those same 1000 dives, chances are you will NOT ever NEED- the pony. It is a game of balancing simplicity versus additional safety.

If you are worried about safety, then sling the pony and you definitely will have an spg. The relevant question pertains to back mounted bottle.