GrumpyOldGuy
Contributor
Spare Air does not give enough air to make a real difference. A diver can literally breathe ten times normal tidal air (about 1-1/2 pints that we normally breathe) when panicked or in trouble. Depending on depth and the volume of the Spare air, a diver can breathe it empty in a minute or two. Also, a spare air can easily be dropped and lost, when passing it off for example, or by the user if it's not secured to the user. We are trained to use second stages on hoses - the spare air is different. Unless you train with it often and in realistic stressful conditions then the chances of failure in a real life out-of-air emergency are high. Another serious concern is that you need one hand to hold the spare air to use it. If things are going wrong you want to have both your hands free! - as they can be when using a pony bottle regulator. A pony regulator is the same as a primary regulator.
stay safe always, good question,
Andrea
teamlgs.com
Sorry, I have a difference of opinion here....
Before I start, I don't own a SA, I would not recommend one and I don't even use my 6cu ft bailout bottle on most dives. I have practiced with it, ascending from 85 ft INCLUDING a safety stop and a 30 fpm ascent rate. Obviously in a OOA situation, I would use more air and skip the safety stop.
The statement about the amount of air in SA not making a difference is simply false. It can make a difference, even it it us just the knowledge that you have a few quick breaths that keeps you from going in full panic mode. If you know you have a few breaths, you are less likely to panic and suck down the little air you have. In reality, its like a leatherman tool, not really good at anything, but when you have nothing else, you might be able to make do with it.
Second, in practice, I have no problem using my 6cu ft bailout with no hands. The bottles are close to neutral underwater, not a big deal.
Third, pony regualtors may be a standard regulator or may be a specialized unit that combines the valves and 1st stage into a single piece to reduce weight.
Lastly, it is nor more difficult to practice with a SA/Bailout/Pony/Twinset than it is with a octo. In all cases, all you really need to do is work it out with you buddy and do it.
SA, bailouts, ponys and twins are all dive tools with diffent operational envelopes. Its good to understand them, each may have their own place for different divers. Reliance on any of these items alone is stupidity, buddies, training and practice are the tall poles holding up the tent.