Cavern In Doubles?

[DeepSeaExplorer]

Divers were exceeding their limits before the internet.

Again, those that want to break the rules will do so with out the internet or despite some restriction put on them by some cert card.

I don't disagree with that... except that the divers that pre-date the Internet were the first explorers. They were developing the 'sport' and eventually established the limits for those that followed, us.

Now the 'sport' is highly regulated and there are hoops to jump thru. Divers know what they are, they just have to 'bite the bullet' and do what's required. Or, you can choose to skirt the system and do sneak dives. I have done it both ways and it's more enjoyable to just do what you have to do...

 

[Mike Edmonston]

If you are trying to stay within NDLs, then you should be using tables. Trying to estimate deco using tank pressure is not safe at all. Are there actually cave instructors who teach that?

Watch me completely miss the point.... Ready.....

VRRRRRROOOOOOOOOMMMMMMMM..................

There it goes.....................

Actually, students are taught to use sun dials, earth's relationship to Neptune, and the distance you can piss in a headwind!

VRRRRRRRROOOOOOOOOMMMMMMMM................

Damn, there goes the whole point of my comment again, Oh well maybe you'll catch it eventually!

 

[WD8CDH]

No, sorry I didn't... I don't think much of your double 35s scenario in the cave - sorry! I suspect that you wouldn't really choose to do that either.

I wouldn't choose either, but given the choice between the two options, I'll err on the side of volume...

You brought up buoyancy. Assuming were still talking about cave diving, on top of everything else, the 35s don't have sufficient weight to offset the exposure suit, resulting in creating trim problems as well. I certainly would not invest the time and effort trying to trim them out. On the other hand, it could be an awesome setup for a shallow reef dive.

I too have issues with the method used to attempt to limit penetration, but I also see a lot of divers trying to learn how to use doubles on the Internet. I personnally think that they should NOT be learning to use doubles and learning to cave dive at the same time. In fact, I would not allow Intro diver to use doubles in the cave, even during a class, unless they have prior training from another course in the use of doubles.

How's that for a radical opinion?

I would still take my double 35s with good regulators over a 190 with a junk regulator that needed my BC to be totally filled to keep me from finning up the silt.

....But I wouldn't do a cave in either of those choices, I was just trying to make a point on how extreame counting tanks as a qualification would be. I agree with your radical opinion. Properly, a diver should NEVER make a "tech" dive of any kind with unfamilliar equipment.

My fav cave rig was 3 close spaced 5.5" diameter 300 bar 75s with two of them on a narrow double outlet manifold and the third tank independant. I have always liked to have the 1/3 for emergencies totally independant, not just an air usage rule. Thats one of the reasons that I like skinny tripples so much.

Your'e right, the double 35's are a great reef rig. They trim much better than a single 80 and comparitivly almost feel like they are not there. They are slightly negative empty so trim is not a problem for me.

Since I am not as Gonzo these days, I usualy dive caves with tripple (2+1) 50s and most other dives with double or tripple 40s.

Chears,

 

[ianr33]

there are hoops to jump thru. ...

Is a hoop jump allowed at the intro level??

 

[Mike Edmonston]

My fav cave rig was 3 close spaced 5.5" diameter 300 bar 75s with two of them on a narrow double outlet manifold and the third tank independant.

Do people ever come up to you and ask you what kind of rebreather that is??

I had a friend diving with an old Aqualung and some chump on the dive boat told him that he had a rebreather just like that, and he regularely takes it to 400 ft. All this on a basic OW cert.

Makes me chuckle

Cheers

 

[Mike Edmonston]

Is a hoop jump allowed at the intro level??

Only with a spool

 

[Jason B]

I think the biggest reason people dive doubles at intro is because they do not want to be singled out as intro divers at the dive site or in the cave. I think a great deal of the hand-wringing over redundancy is window dressing.

You see a diver in a single tank puffing off an O2 bottle at 20' or swimming up hill 400 you might have a word with them about the importance of diving within training limits. You see the same diver in double tanks you assume they are qualified for whatever dive they are doing. Allowing intro divers to play dress up in my opinion hampers our ability as a cave community to use peer pressure and the threat of discovery to keep people diving within their limits.

I do not have any problem with people diving doubles at the intro level if they are going to be taking an apprentice or full class and want to hone their cave skills in doubles beforehand.

Again, if someone at the intro level wants to cruise up the hill 400 they are going to do it.

Your trying to put a mark to identify intro divers is ridiculous and would surely not solve the issue for the reason mentioned in my first sentence in this post.

An unsafe mind is an unsafe mind. Silly rules can't save the dumb, but it could kill an otherwise safe cave diver who suffers a tank neck O-ring blowing at max penetration.

 

[DeepSeaExplorer]

Is a hoop jump allowed at the intro level??

Actually, multiple hoop jumps are required. The details of excuting the 'hoop jump' are only revealed during the class.

I use to have a spool with no line on it that I pulled out for visual jumps. It's the same concept.

 

[SparticleBrane]

Nobody ever died from having too much gas...
I agree with Jason. Some people just have to push the limits -- nothing and no one is going to tell them any differently, until they burn their hand on the stove.

 

[Daedalus]

Silly rules can't save the dumb, but it could kill an otherwise safe cave diver who suffers a tank neck O-ring blowing at max penetration.

When has this _ever_ happened? Is it unsafe to do a cave dive without a jack to lift up the cave if it collapses on you? If you have a failure like this at max penetration you either have been grossly negligent in your maintenance or you got caught stealing from the collection plate and the man upstairs has it out for you.