A Case for Spare Air

[ReefHound]

It's not difficult flying with a 19 cf pony, I've never had a problem, checked or carry on.

How many do? I'll bet there are lots of divers with a 19cf pony who leave it home when they fly.

How much does a Spare Air weigh? How much does a 19cf w/ regulator weigh?

People are comparing Spare Air to standard pony bottle. There's no comparison, the pony is better. But many do find it heavy and bulky and so don't bother with it. Then the comparison is between Spare Air and No Spare Air.

 

[Bob DBF]

I read the thread as A Case of Spare Air, and thought the thread was going to be humorous.

I got one back in the day and found it could not handle the conditions I dove in so I quit taking it and was eventually sold.

When I got the Spare Air I figured an extra breath in an emergency would be handy, when it didn't work out I did not buy a different redundant supply, I went back to business as usual. I was still young back then. Now I carry a 19 on the deeper dives.

It is not the fault of the gear that some divers don't understand gas management and believe they will magically get more air than the bottle can give them. This is a problem with training and advertising, not with an inanimate object.



Bob

 

[Will_A]

scubadada and markmund I appreciate the tips on travelling with a pony bottle. Good to know. However, if I am planning for a lengthy trip with clothes, work equipment and electronics, cameras and a single dive bag, those weight restrictions will still probably keep me using a Spare Air over a larger pony bottle.

wetb4igetinthewater Thanks for sharing that Dive Planning PDF. Good stuff. I do recognize that under stress one's rate of air consumption may be much higher. But, part of the reason I like to use the Spare Air at the end of dives is to get comfortable with switching to a redundant air supply smoothly, quickly and in doing this hopefully reducing the stress if this event ever happened for real. I'm not taking any of my measurements as gospel, just that in the situations I mentioned having some air would be better than having none. I'm absolutely sure I'd be considerably more stressed having an OOA emergency without a redundant air supply.

BurhanMuntasser I'd not consider a Spare Air as much of a safety tool in an environment where the biggest risks were serious entanglement or getting blown up! It would also be of little comfort in wreck penetration or any overhead environments. But for my kind of recreational diving, I think it would be helpful. My biggest OOA fears would be that I did something stupid and now I am out of air. Secondary to that would be some sort of equipment failure that left me out of air. In these limited situations at recreational depths, I'd rather have it than not.

 

[ReefHound]

scubadada and markmund I appreciate the tips on travelling with a pony bottle. Good to know. However, if I am planning for a lengthy trip with clothes, work equipment and electronics, cameras and a single dive bag, those weight restrictions will still probably keep me using a Spare Air over a larger pony bottle.

With the steep baggage fees for extra bags and bags over 50 pounds, I usually check one bag at 44-48 pounds and my carry-on is pretty heavy too. Spare Air 3.0 weighs 2.2 pounds. I could work that in with little or no adjustment. 19cf weighs about 8 pounds and regulator will add another 2-3 pounds, so 10-11 pounds. That would require significant adjustment. It could be done but not what I would call "easy".

 

[TMHeimer]

I have to think why I ran out of air underwater before anything else. In my environment, the biggest hazard for me after dynamite fishing is getting caught on fishing lines, nets, debris or anything that would impede my ability to ascend to the surface on time before I am able to cut myself out of the entanglement. I have to have enough air not to get back to the surface but to be able to cut my self out of the entanglement and then make my ascent. Spare air isn't going to cut it at all especially when considering the "excitement" and dramatic increase in breathing rate. 30cuft is minimum for me but it depends on depth and various other factors. I do it with a 40cuft or an 80.

If I had those entanglement possibilities I would do exactly what you do. Haven't seen fishing line, etc. here, but I even keep a few feet above harmless eel (sea) grass. Sometimes it can be over 5 feet tall and I wouldn't want to be tangled in that without a good size spare tank.

 

[wetb4igetinthewater]

@ReefHound,

2.2 lbs is still significant. For the depths you are talking about, you're better off spending money on training where you don't feel you need this unnecessary crutch at 30 feet.

 

[ReefHound]

@ReefHound,

2.2 lbs is still significant. For the depths you are talking about, you're better off spending money on training where you don't feel you need this unnecessary crutch at 30 feet.

I'm not the one talking about those depths.

 

[ChuckP]

Just a historical note that some might find a way to apply here....

I recently saw a PBS show on the history of the SeaLab project, and they started with early research by the Navy that eventually led to SeaLab. They wanted to check out potential procedures for escaping from a submarine, so they took a submarine to 320 feet and had two people do a buoyant ascent from there. (That is a CESA without the C--they had an inflated vest and went up quickly.) They had no trouble exhaling all the way up from 320 feet, going much faster than the standard CESA ascent rate. They were just fine on the surface.

I think I'd be ducking my head and hiding in the back when they asked for volunteers for that program.....Yikes!

 

[wetb4igetinthewater]

I'm not the one talking about those depths.

What is the point of running out of air twice?

 

[BRT]

What is the point of running out of air twice?

Would you rather run out of air deep or shallow?