Spare Air

[Tuytles]

There was a thread not too long ago on the Spare Air version marketed for Nitrox. Some felt it was a marketing gimmick, if I recall. What @BRT said above was also discussed. I'll try to find that thread.

By the way, weren't you in my Fundies class with Doug Mudry in 2014?

Lorenzo Hi!
How are you?
Yes, I was in that class. Haha all the memories of the little house on the springs just came flooding back!
It was one of the turning points of my dive training. Was worth every penny and second of my time!
I got a provisional and had planned to go back after I got more diving under my belt. See, I took that course with only about 30 dives experience haha. Still practice most of the methods but now that I get to help new divers getting certified with PADI, I do change up teaching styles with their curriculum in mind. Want to continue with the training at some point with GUE. One of my favorite parts of diving is getting to learn all the best training methods and techniques from all the training organizations. Thank you kindly for the link to that article on SB, will check it out.
What are you up to diving wise these days?

 

[Tuytles]

I wish people would do the calculations of what their ascent rate would be based upon an estimated elevated RMV from various depths.

I wish people would do the calculations of what their ascent rate would be based upon an estimated elevated RMV from various depths.

Good point. I know my average SCR and gas calculations for the conditions I dive. Not asking for myself but for all OW divers in general. I’m not really asking about the amount of air being sufficient for any particular task, just general actual diver experiences with the spare air.

 

[Tuytles]

If you were going to carry extra gasoline on a road trip, would you just bring a quart or would you like to have a few gallons? If you went shopping and wanted to bring along some extra money would you just bring an extra 2 dollars or would you like to have more like 10 or 20 dollars? The same is true for bringing along extra air if you are going to at all. If you are going to clip on a Spare Air, you might as well clip on a small pony (19 CF) and bring a quantity worth having.

I like your analogy.

 

[johndiver999]

A 6 cu-ft pony bottle might be enough to allow a diver to ascend directly from 60 or 80 feet or maybe more, but from my understanding, the spare air is designed to have the mouth piece rigidly attached and the entire bottle is held by the teeth on ascent - not using the hands. Is that correct?

If that is correct, a 6 cuft bottle seems like a pretty big thing hanging from your mouth with no support. I am curious if I am right about the (hands free) deployment/use and some first hand reports of how it feels. There is also the option of using a 6- cuft bottle with a more convention pony bottle set up.

I always think it is more useful for a diver to run through the math of how much air they will use on ascent FOR THEMSELVES, rather than withstand dozens of subjective arguments of this is too little or you are going to breath like a freight train in a real emergency, or you will run out twice, or a safety stop is mandatory etc.

 

[Tuytles]

I almost always dive with my wife. Sometimes we hold hands. In green water we are never very far apart. But sometimes in blue water we find ourselves far enough apart that in an emergency I'd go up rather than chase her down. You can disparage that, but my experience since 1985 is that buddies being somewhat separated in clear water is more common than uncommon.

I've told this before, on a wreck at around 120 feet, hanging on the higher part, slightly narced, watching a group try to shoot a fish through a hole in the deck well below us. A lady went head down to look in a hole and then I watched her calmly swim to the DM and take his spare reg and they started up. When she went vertical her air just shut off. As we went slowly up I considered how far it would be with NO air, and decided a few breaths would be an advantage.

Thanks for the anecdote from that experience. These are kind of the things I was looking forward to reading. My main thought was to help new divers avoid a strict out of air emergency ascent in case their buddies or the dive operator proved unreliable.

 

[Tuytles]

A 6 cu-ft pony bottle might be enough to allow a diver to ascend directly from 60 or 80 feet or maybe more, but from my understanding, the spare air is designed to have the mouth piece rigidly attached and the entire bottle is held by the teeth on ascent - not using the hands. Is that correct?

If that is correct, a 6 cuft bottle seems like a pretty big thing hanging from your mouth with no support. I am curious if I am right about the (hands free) deployment/use and some first hand reports of how it feels. There is also the option of using a 6- cuft bottle with a more convention pony bottle set up.

I always think it is more useful for a diver to run through the math of how much air they will use on ascent FOR THEMSELVES, rather than withstand dozens of subjective arguments of this is too little or you are going to breath like a freight train in a real emergency, or you will run out twice, or a safety stop is mandatory etc.

Hmm, good point. I imagine if it too heavy, a diver could hold it. I doubt in an emergency ascent they’re going to be doing any kind of task loading other than possibly dropping weights etc.

 

[Tuytles]

The OP is listed as a DIR Practitioner and is asking about Spare Air. I smell a troll.

Definitely not a troll. As Lorenzo said, that label is given when a diver has trained through the organization and has access to those threads. While I do practice most of their methods when diving personally, my original question was posed as a general inquiry to divers who have used the spare air. I am thinking of possibilities for newer OW divers training in other organizations.

 

[Bob DBF]

My main thought was to help new divers avoid a strict out of air emergency ascent in case their buddies or the dive operator proved unreliable.

The best way help OW divers is to increase there watermanship skills. The Spare Air can be used to assist a CESA, however one can not be in near panic mode when doing it.

When I started diving, after years of snorkeling/freediving, one way to end a dive was an OOA event, because SPG's were not in general use, and j-valves may not be on the tank or used properly. Because it happened enough, it was not the panic inducing issue of the first OOA the diver ever had. Also someone that has spent a lot of time in the water and freedives knows they have more time to deal with an issue than a diver without that experience.

The best thing you can do for your divers is get them at home in the water, and teach them about freediving. It will give a perspective on the OOA experience.

Safety in the water has nothing to do with how much, and what type of gear you carry. If necessary, one should be able to ditch it all and swim home.


Bob

 

[Diver below 83]

I’m looking to do a 19cf mounted onto my plate.

 

[NAUI Wowie]

I hear that over and over. But on the actual dive boat in Mexico nobody brings the extra 5 gallons or $20. The actual choice seems to be between a Spare Air, or nothing. Given that set of options, I like my Spare Air. I have had people carrying no extra air tell me they don't believe my Spare Air in necessary. So far they have been right. I'll be really happy if I end my diving career with the conclusion that I never needed one. I could carry another reg set and a 19cf tank every trip but it would affect my packing quite a bit.

i fly with my 19cf every year to mexico and every year to cebu philippines. the extra reg goes in my carry on backpack and i lose 9 or 10 pounds of my 50 in my suitcase. I quickly realized that I only need 40 pounds in suitcase when you can carry on a backpack and one large computer bag .....

once used to it all its no trouble at all. Not saying dont use spare air just saying if you are doing it maybe consider a larger 13 or 19 cf.
I do wrecks in cebu and would in mexico as they are the most fun you can have underwater. well never did caves so that may be more fun. Also I have my perdix A.I. set to two transmitters. I only run two hoses off my main reg this way and dont worry about failures as I carry a second separate air in my pony.

people say they want to know the air left if the transmitter goes out but with a pony you have backup so you would just head up IF you have a malfunction and you wont run out of air no matter what....