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Post by cnotthoff on Apr 6, 2008 11:13:20 GMT -8
If you've read any of my others posts, you know that I do not regularly dive vintage equipment, but I have been in the dive instruction biz for quite a while.
I've seen a number of threads dealing with instructional agency guidelines and liability. Most of these address the current standards requiring a back-up air supply.
My question comes from experience long ago, that doesn't involve diving at all. My first car was a 1929 Model A Ford. No, I'm not that old, this was in 1972. That car was fun to drive and taught me things that stick with me today. When the engine died while I was shifting, I'd retard the spark, increase the throttle on the steering post, step on the starter button, then double-clutch it back into gear. It was great to learn how to work on a car that didn't have a fuel pump, or hydraulic brakes.
As much as I loved driving that old thing, I never relied on it to get me where I was going. It was for short trips, and I always carried an AAA card. I got towed home a lot.
Would carrying a Spare Air (your AAA card underwater) as a back-up air supply violate the spirit of diving with vintage equipment? That would meet the CYA requirements of most agencies, without altering you gear. It would allow an instructor to develop students' skills like sharing a double-hose reg, while having a safe alternative air source right there.
The concept of self rescue being an Emergency Swimming Ascent to the surface works well for most recreational diving. I've done them from 100 ft. just to be sure I can. As divers go deeper and into places where the surface is not accessible, that concept doesn't work. I trust reasonable vintage equipment enthusiasts are not going under the ice with a 50-year-old regulator and no redundant air supply.
The pros and cons of sharing knowledge through accredited training agencies, or getting manufacturers to market new versions of old favorites is a whole other topic. I'm just wondering if an inconspicuous Spare Air could keep their lawyers happy.
Good Dives,
Charlie
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Post by Nemo on Apr 6, 2008 11:31:07 GMT -8
Charlie, I agree. Survival is the most important goal of SCUBA diving. Do what gets you home. Spare Air? Better to have and not need, than vice-versa. As for what "purists" might think: who cares? It's not going to be any consolation if my last thought before drowning is, "Well, at least I was using 100% authentic gear." VBR, Pat
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Post by VintageBob on Apr 6, 2008 14:07:11 GMT -8
Charlie,
I use one of my vintage double hose regulators 98% of the time. Actually the only vintage gear that do I use are the 2 hose regulators and vintage 71.2 tanks. Regardless, of what regulator I am using I ALWAYS have either a Spare Air or a 13 cu ft pony bottle, which I also use to run my BC, when I dive with the single stage Mistral. When I use one of my two stage regulators, the Aqua Master or Royal, I have an attachment fitting to the Hookah port that provides me with an LP hose for the BC and an Octo. I learned early on that I tend to over exhale on practice free ascents, so I now just carry an alternate air source.
So I'm not much of a purist, but I have a great time with the old regs. and I try and be safe about it.
Vintage Bob
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Post by Terry on Apr 6, 2008 14:31:31 GMT -8
Hi Charlie: I agree with you 100%. I really enjoy vintage diving, and most of my dives are solo; so I carry a 3.0 Spare Air with me on most of my dives. I have a great deal of trust in my equipment whether it be one of my vintage two hosers or one of my modern single hose regs; but I've always been one to factor in the "WHAT IF'S, and try to keep "Murphy" from accompanying me on any dive. ;D Terry
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Post by SeaRat on Apr 6, 2008 16:57:39 GMT -8
Well, I'm going to deviate a bit from what's said above. Realize that my diving is mostly shallow, and that if I need it, I have an AMF Trieste II set up with an octopus. But the vintage equipment is pretty fool-proof from a failure modes and effects point of view. If either a Aquamaster or Mistral fails, it always fails as a leak of air. Neither fails with a shutting off of air. As for diving under ice without a spare air, why carry a spare air, as it is prone to freeze-up by its design, whereas an Aquamaster is not. I have two Sherwood valves with duel posts, and sometimes dive my double hose regs with a single hose reg on the cylinder post. I did this a few years back when testing a Healthways Scuba regulator, thinking that it might fail as the exhaust was modified. It did not, and I did not need to use the spare second stage. But in regular diving environments, a double hose regulator is a pretty reliable source of air. Now, if diving with students, a buddy who doesn't understand buddy breathing, etc., then I would dive an octopus or second regulator (like a Spare Air). Those are different circumstances. One thing about Murphy, is that with more gear, things get more complicated, and there can be a greater potential for Murphy to show his face. John
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Post by nemrod on Apr 6, 2008 19:07:48 GMT -8
Yes it would violate vintage standards. Yes, you can use one if you insist, nobody is going to refuse to talk to you if you show up with a pony, snicker maybe . As to lieyers--are you planning on sueing yourself for drowning yourself? Spare Air is essentially a waste of time and insufficient to be of any real value. If your going to carry a redundant air supply then carry a pony---vintage or not. An octapus is not a redudndant air supply, it's only fucntion is simplified air sharing. FACT, a good and well maintained Mistral or DA or Royal or similar Voit are at least as relaible as any modern regulator and probably more so. Do you carry a Spare Air when you dive your latest plastic toy regulator? Here I am at 140 feet on the deck of the Mighty O twenty six miles from shore. I am not diving vintage but I am using my favorite and most relaible and best regulator, a Phoenix Aqua Master. I have an octopus second on a 40 inch hose with swivel to facilitate air sharing with "modern" trained divers from the Phoenix first stage. I have a pony bottle, 19cf, also to facilitate deep rescues of OOA divers and or extracting myself from a similar circumstance, full redundancy. I am on 30% Nitrox, 32% in the bottle. It is also along for emergency deco assist considering the depth, current, wildlife. As you can see below, this diver, also has a 30 cf bottle for the same reason. The operators don't want you on doubles unless doing a planned deco tech dive and yet the depths are to great to safely dive on a single 80/95 without some bail out plan for contingencies. Last year this operator alone brought up 17 flat out of air divers from below 100 feet. Therefore, carry a pony if you wish but not because your double hose is unreliable but because the circumstance dictates prudent exception to "vintage' rules. Rules used loosely there, they are mostly just guidelines. Nem
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Post by luis on Apr 7, 2008 6:49:19 GMT -8
I totally have to agree with John post above. I would much rather use my properly maintain double hose under the ice than a single hose (and I have). Reliability and Mean Time Between Failure (MTBF) calculations are hard quantify, but my experience and just counting failure points you should get a fairly concrete idea that many vintage double hose are far more reliable than most modern regulators. Most double hose are also environmentally sealed…both first and second stage. The use of an alternate air source is not at all a bad idea if the dive merits it (like under the ice or deep, etc.). I have shown on a different thread that a pony and alternate air source (including an octopus out of the hookah port) was used at least as far back as 1965…therefore it can be included as vintage. Some may not like it, but we can’t rewrite history. vintagescuba.proboards2.com/index.cgi?board=instruction&action=display&n=1&thread=1162&page=2I agree with Nemrod in that a “Spare Air” is probably not the best solution. Personally I also feel that a pony is a better solution, but as long as you know the limitations of a spare air, I guess it is OK for relatively shallow dives. Personally, on most of my dives I use an alternate second stage (octopus) attached to my Phoenix, because I dive with non-vintage trained divers. I have practice buddy breathing (air sharing) with my double hose with my wife and basically we need to practice it more. But, unquestionably an octopus would be more comfortable if needed. I also dive with a variety of other modern divers. Most of the time I dive a totally eclectic mix with a back pack harness/ BC totally modified by me and a Phoenix Royal Aqua Master…again a modification design by me. The Phoenix allows all the modern regulator attachments…therefore I consider it an eclectic regulator.
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Post by nemrod on Apr 7, 2008 7:10:20 GMT -8
An octopus would not really be a redundant air source for overhead diving. Redundancy is not really a vintage concept anymore than would an octopus rig be a vintage rig but instead more inline with today's DIR methodology.
For redundancy you must have:
1.) A pony/spare air etc
2.) A Y valve on a single with the ability to isolate and double regs
3.) Independent doubles
4.) Isolation manifolded doubles with dual regs
An octo is only for airsharing and does not provide any real redundancy.
nem
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wd8cdh
Regular Diver
Posts: 35
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Post by wd8cdh on Apr 7, 2008 7:48:04 GMT -8
A steel 1/2" tapered pipe thread size D or E O2 tank with a post valve and an early single hose regulator (I use a Conshelf or Poseidon 300) would make up a true vintage pony.
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Post by luis on Apr 7, 2008 7:55:08 GMT -8
An octopus would not really be a redundant air source for overhead diving. Redundancy is not really a vintage concept anymore than would an octopus rig be a vintage rig but instead more inline with today's DIR methodology. For redundancy you must have: 1.) A pony/spare air etc 2.) A Y valve on a single with the ability to isolate and double regs 3.) Independent doubles 4.) Isolation manifolded doubles with dual regs An octo is only for airsharing and does not provide any real redundancy. nem I agree with your post except for your personal definition of what is vintage. An octopus is not really a redundant / independent air source if it is sharing the same first stage. I meant to say alternate second stage instead of alternate air source…the pony was already referring to the actual alternate air source (both of which were commonly used in the 60's in the North East).
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Post by nemrod on Apr 7, 2008 8:33:28 GMT -8
Yes, I realize that but nonetheless community standards like industry standards are a concensus and it has long been held that octo rigs are not really vintage era configurations and that the vintage ERA concluded sometime in the very early 70s----marked by the appearance of power inflated BCs in COMMON use and the wide spread use of octo rigs, spgs and the end date production of the Aqua Master. Of course, a concensus can evolve but I just don't see those types of configurations in any of the few texts I have available to me. If three or four people did something in 1965 that does not make it common place and the picture I think you showed was not a octopus but a pony unless I am looking at it wrong. I am not sure that is a personal definition since it is an amalgamtion of those read here over the last several years and disscussed along with the formation of NAVED such as it is.
Civil War infantry may have had a few center fire rifles about but that does not make a 30-06 Springfield Civil war authentic, just as an example.
Nem <---stubborn
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Post by luis on Apr 7, 2008 9:16:08 GMT -8
A steel 1/2" tapered pipe thread size D or E O2 tank with a post valve and an early single hose regulator (I use a Conshelf or Poseidon 300) would make up a true vintage pony. I used to have one of those tanks as a kid. I never actually used it as a pony since I didn’t feel a need for it in the Caribbean. I actually was going to use it as a utility small tank to go get the anchor after diving and similar quick jobs like that. I wish I could find one or two similar tanks. All the portable O2 tanks I deal with now a day are straight thread aluminum cylinders. Oh Nemrod, I don’t mean to start a new civil war.
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Post by scubadiverbob on Apr 7, 2008 13:13:38 GMT -8
If someones diving a single hose they should have a spare air. They aren't as reliable as a doublehose and might fail (excluding the "new mistral"; a modified single hose). Hey wait ... I've never had any reg fail on me except for freeflowing ... didn't need a spair air for that. I used my spair air for going down cliffs to dive spots not accessable with scuba; unless you have a helo. Got to go. chat later.
Robert
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Post by cnotthoff on Apr 7, 2008 16:12:21 GMT -8
I agree with John and others. A Spare Air is not meant for any overhead environment, especially ice. I can imagine the looks I would get if I eschewed my 30 cuft pony bottle for a Spare Air on one of my deeper dives.
I merely suggested it as a way to meet standards to allow an instructor to teach a vintage equipment specialty course. If you are not teaching professionally, you don't have to worry what the lawyers say. I've been happy to be able to say I followed standards when called into a deposition.
I readily admit to being a rookie in this forum. I've seen a few posts about NAVED. What is NAVED?
I enjoy reading all your comments on this subject.
Charlie
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Post by luis on Apr 7, 2008 17:33:20 GMT -8
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