Spare air - or not?

[doctormike]

I have one from way back when. I dove with it but found the conditions I was in would crud up the reg and although it was never used, except as a pool toy, I had to service the reg every time out, after a very short time it found a place in a drawer. I'd sell it but my conscience would bother me.

Yup, that's another issue. The whole thing costs $249, regulator and tank, so you know that we are not talking about very high end gear here. I often hear about people spending whatever they can on their primary regs, but then buying something cheap for the octo or for their pony bottle, since "hey, I don't plan on using it much"..!

If anything, the backup system should be MORE reliable, since you won't know that it's having a problem until you need it in an emergency situation. This is the reason why many divers standardize on one type of reg for their primary, their secondary and their alternate gas source.

Sometimes, false security is worse than no security. Yeah, if you just needed that one breath, you would give everything you owned in the world for it. But I wonder if anyone has looked at the effect of the presence of a Spare Air on gas planning in new divers. I would bet that just the fact that they were carrying one would make a new diver a bit less attentive to their gas (something that is already a problem), since they have a "parachute" to rely on.

 

[DivemasterDennis]

I am of the "no spare air" opinion, but I want to comment on a phrase in the original post "chasing after a buddy out of air." If buddies stay in proper proximity, you are never going to have to chase after them or they you If you plan your dive and dive you plan, you won't run out of air. In the event of an equipment malfunction (rather than dive planning malfunction) you should be close enough to your buddy to access their alternate air source. Hence the "no spare air" position.
DivemasterDennis

 

[BDSC]

The problem with this line of thinking ("if you were in situation X you would be happy to have gadget Y") is that you can construct a thought experiment with unusual circumstances to support the use of almost any device.

Like one of these? (Unless you are solo diving)

At home, I sling a 30 CUF pony

 

[DandyDon]

It's good to have a SA thread now and then...

At home, I sling a 30 CUF pony, and I don't even notice it. In the Caribbean, I don't (too hard to bring it logistically), but I'm almost never below CESA depths.

Another thing to remember is that this is a scuba tank and regulator, so it's not the kind of thing that you can just throw in your bag and forget about. Like all tanks, they need to be visually inspected after being emptied, which is what you would need to do if you were to fly with them. And like all regulators, they require regular service even if you aren't using them.

My pony flies anywhere I do. I keep everything clean, reassemble, and fill. It's for my bail out so as long as I am confident, I have it vized once a year.

Finally - they don't really sell a Nitrox model, do they? Is that so you can get an extra few seconds of bottom time before your emergency ascent?

Yep, which you have to breach to fly, so no one is going to partial pressure fill it, therefore there is not difference in the 2 models other than price - hence my ripoff remark. Not insulted enough? They make a baby SA: 1.7 CF.

They did make a 6 CF, but discontinued the only one worth considering.

Mine are now up for sale. Gittem while they last!
http://www.scubaboard.com/forums/cl...2-two-used-spare-air-systems.html#post6094181

Got the yoke for those...? :silly:

 

[doctormike]

Like one of these? (Unless you are solo diving)

Notice that I didn't comment on the "poor buddy skills" aspect of the discussion that others mentioned. Diving in murky waters in the northeast with currents, I know that buddy separation can happen fairly easily. I don't think that I'm alone in that line of thinking.

So as far as the pony being no different from the SA in terms of the window of utility, I think that the difference between 30 CUF and 3 CUF should be readily apparent.

My pony flies anywhere I do. I keep everything clean, reassemble, and fill. It's for my bail out so as long as I am confident, I have it vized once a year.

Sounds good! Do you need to have it vized once you arrive after flying to get it filled, or do you avoid that by filling it from your tanks with a Transfill whip?

 

[CaveMD]

You guys are crazy, spare air is the greatest thing ever, I keep one mounted just above my can light and on top of my snorkel for cave diving.

 

[DandyDon]

Notice that I didn't comment on the "poor buddy skills" aspect of the discussion that others mentioned. Diving in murky waters in the northeast with currents, I know that buddy separation can happen fairly easily. I don't think that I'm alone in that line of thinking.

So as far as the pony being no different from the SA in terms of the window of utility, I think that the difference between 30 CUF and 3 CUF should be readily apparent.

Sounds good! Do you need to have it vized once you arrive after flying to get it filled, or do you avoid that by filling it from your tanks with a Transfill whip?

I got mine because of poor experiences with buddies early on. Many cars are sold without spare tires now, but I like backup. Mine came with a tiny tire so I have a plug kit and portable pump. As long as I am happy with my pony and valve being kept clean in transit, I just put it back together and take/send it to the fill shack.

 

[doctormike]

As long as I am happy with my pony and valve being kept clean in transit, I just put it back together and take/send it to the fill shack.

Aha. I have heard that some shops won't fill empty tanks without a viz. Maybe that's not universal..

 

[CaveMD]

Aha. I have heard that some shops won't fill empty tanks without a viz. Maybe that's not universal..

I know the shop I work at wont fill empty tanks, it's common but not universal.

 

[CaveMD]

Jokes and BS aside, I really think anyone considering buying a spare air should look into sidemount diving.

It's not just for cave divers squeezing through 7" tall rabbit holes. My girlfriends mom absolutely has zero interest in technical diving(much less caves) and she only dives sidemount. You have two equal sized "spare air's" on either side of you, and they are easier on your back. When walking out of water with the tanks they give you a lower center of gravity and are much safer on a rocking and rolling boat. I put every piece of backmount gear I own up for sale after just a week of sidemount diving.

My sidemount instructor teaches for PSAI and they actually will even teach open water in sidemount, he has two students who have never worn tanks on their backs.