computer useage in DIR ? ?

[Charlie99]

Braunbehrens once bubbled...
Sorry, Charlie, but I'm not going to do deco lessons on the 'net. Just doesn't make sense. .....
Braunbehrens further bubbled...
Rotourner, don't take this the wrong way, but no. I don't think it's appropriate for me to give out info that someoene could use to get in real trouble if they misunderstood it.

Hmmm. That doesn't seem to stop you on any other question. Perhaps you don't really have an answer. Perhaps your system works for the diving you do, but that diving has never included a liveaboard trip with multiple dives per day.

Various agencies other than GUE are open about their courses and have books available. The DIRF manual has no information regarding calculating multilevel dives, other than advising divers to avoid computers. A GUE instructor comes on this board, rails about how bad computers are because they use Haldane models instead of RGBM, but the dive planning program sold by GUE is pure Haldane.

Re your hiker analogy: I see the DIR attitude as the hiker saying "I don't need no stinking compass or GPS, I pay attention to where I am". A prudent hiker brings a compass, maps, and knows how to take advantage of a GPS while not relying upon it exclusively.

 

[Charlie99]

MikeFerrara once bubbled...
I've argued this a lot on this board. Yes, they say you don't need a computer. But...if you ask why they say take a DIRF. But...they don't teach much of it in DIRF and some haven't been tought anything on it in DIRF. What they mean is they don't need a computer I guess.


I think what Braunbehrens is trying to tell you guys is that if you know what kind of deco you want to do and how it fits the profiles and gasses you dive that you don't need a computer to do it. Pay attention to what he writes. He repeatedly points out that deco isn't the exact science some think it is. I think he is right.

Read the points he listed above. Much of it is taking an educated guess based on decompression knowlege and past experience. It does work. There is no single magic GUR formula that can be learned in a day that frees you from the computer for all time.

Your statements about this not being taught in DIRF doesn't match statements made on this board by MHK, who is a GUE DIRF instructor. Interesting discrepancy.

Of course there are many types of diving where it is much better to do a multigas plan on a PC or Palm, write down the classic variants (just deeper, just longer, deeper and longer, quick bailout) and go diving.

There are lots of other types of diving (single AL80 repetitive diving, particularly on a liveaboard) where firing up a PC doesn't make a lot of sense. One can fudge and estimate, but IMNSHO, it a lot better to use a computer and use your fudge factors and estimates to do a validity check on the computer.

It is also clear that one can dive safely dive without a computer since whether or not you stay inside NDL is not important provided you have adequate gas and do appropriate stops. I suspect that this is really the DIR method, but with many of them not realizing that NDLs are being exceeded.

My frustration is that repeatedly DIR or DIR wannabe divers make blanket statements saying the use of computers are bad, and when asked for a description of how they would handle repetitive multilevel dives, they fail to make any reasonable suggestions.

 

[Braunbehrens]

Mike, you are dead on!

The rest of you guys are pretty funny. I give a DETAILED account of how to proceed, but you want everything served up on a silver platter. Give me a break!

This is EXACTLY why I'm not going to serve it up. You don't want to take the time to understand why these rules apply, you just want to know what they are. That's just how you get hurt.

Ironically, that is also what you guys always criticize about DIR. "You guys just blindly follow what Trey says..."

Well, I'm sorry to disappoint you, I don't blindly follow anyone, and I'm not going to make it easy for anyone else either.

You want to do deco without a computer? Then LEARN about deco. You don't have to take a GUE class to do it, just talk to some people (like Trey, or MHK, or Dr. Deco), and/or read some of the research, use some common sense, take a look at some deco programs and do some dives.

I'll even get you started. Take your favorite deco program and run a bunch of tables using air. Then run the same program using O2 for deco at 20. Notice anything? If you do, and it always works, do you really need to use a computer or carry tables for air and for O2? (I'm just using air as an example here).

Remember also that we use a limited number of gasses. You will never learn anything if you continually use a hundred different gasses. If you stick to a couple bottom mixes and a couple deco mixes everything clears up.

The problem is that all this stuff hangs together. You can use this small part and that small part, but in the end you can't be sure that the whole system works, unless it's been tried out. I know of only one such system that has been extensively tried out.

I don't know why I even bother....and people say the DIR crowd is unfriendly! I should put together a collection of the replies I get from the non-DIR people.

Try to keep it friendly please. We are all just divers trying to have fun...

 

[jonnythan]

Charlie99 once bubbled...

My frustration is that repeatedly DIR or DIR wannabe divers make blanket statements saying the use of computers are bad, and when asked for a description of how they would handle repetitive multilevel dives, they fail to make any reasonable suggestions.

I'm glad I'm not the only one who feels that way.

I suppose you could use some software like GAP to plan your non-deco repetetive dives for the day, but the problem is that they allow no deviation. If you and your buddy have 1200 psi of air left at 30 feet where you planned to have 900, so you want to spend an extra 5 minutes, you couldn't because it would screw up the rest of the diving that day and you'd have to run the numbers again.

The no computer thing makes sense for deco dives or dives that are goal-oriented.. the "mission" dives.

It just doesn't make any sense for the "checking out the wreck at 45-60 feet til we hit our rock bottom gas" dive followed by "swim around the helicopter at 35-55 feet" dive or "check out the reef, staying above 60 feet" dive.

 

[GreenDiverDown]

Well, PB...

I am actually very much pro DIR, so much so that it is one of the main reasons that I have given up teaching basic open water. In fact, it has changed my diving in every way...and in some ways not for the better. My problem with you is that in my opinion you are a poor DIR representative and actually do more bad than good for DIR...well... at least here on the board.

And as far as computers go... most of mine live in guage mode and I use tables most of the time...ah...rec diving only, by the way. Sometimes I do use a computer. But I also follow the rules of computer use, do reasonable and appropriate profiles, and have appropriate surface intervals. I have fun and I feel that I'm pretty safe.

I'm not ready to condemn the use of computers and I think many rec divers can benefit greatly from their use.

Oh, BTW, I have never had anything served on a "silver platter".
I've worked HARD for everything I have...including my skills and knowledge related to diving. Actually, I don't think I want anything from you.

But it would be nice to discuss DIR dive planning just like we discuss other things. It's just wierd that everytime the topic comes up it gets an immediate... shishh. I say it's about time that we talk about it.

SA

 

[Charlie99]

Stephen Ash once bubbled...
But it would be nice to discuss DIR dive planning just like we discuss other things. It's just wierd that everytime the topic comes up it gets an immediate... shishh. I say it's about time that we talk about it.

If it's not "shissh", it's a rapid change of subject. I am trying to converse about why computers are, or are not appropriate for multilevel, repetitive NDL diving using a single gas, with AL80. PB, in his last post starts talking about deco at 20' with O2. Jeesh.

To be very clear, I am inquiring about ways of tracking and calculating NDL on repetitive multilevel dives, using AL80 tanks with a single gas. IF you DON'T choose to track NDL, and just have general rules that will ensure that you have completed deco by the time you get out of the water, just say that.

When someone makes a statement that computers are inappropriate for a particular use, it would be nice to find out what they think IS appropriate.

I guess for some DIR guys, listing a bunch of platitudes is easily confused with dishing things out on a silver platter.

PB tells me to learn about deco. Interesting statement, Paul. You don't know me. What I do know about deco might surprise you.

Charlie

p.s. My bailout tables for rec diving are very small, just a 3"x4" extract of DCIEM NDLs, and limits for 5, 10, 15, and 20 minute deco -- just 50 numbers total.

For multilevel predive planning, I use an enlarged printout of the backside of PADI RDP (RNT table), with all of the SI information of the other side replaced by a row of numbers I have added across the bottom of the RNT table. The multilevel dives are treated as multiple dives, with "0 SI".

As for repetitive diving, the tables use the 60 minute compartment as the controlling factor, my computer uses reciprocal offgassing while submerged, but has 60 min credit control upon surfacing, so the computer and tables track fairly closely. It is also a trivial matter to compare a few predicted NDLs by the computer and compare that to what the table assumes at that same SI time.

(See PB -- it IS possible to give a general description of a method used, without giving out info that can get people into trouble).

 

[Braunbehrens]

Stephen Ash once bubbled...
Well, PB...

My problem with you is that in my opinion you are a poor DIR representative and actually do more bad than good for DIR...well... at least here on the board.

Please explain this statement. Why am I a poor DIR representative, and how do I do more bad than good. If you are going to accuse me of something, please be specific and give me specific examples.

Thanks.

P.S. It is not my intention to hit anyone over the head with a 2 by 4, like some DIR advocates do. I simply explain the reasons behind the choiced I've made. If I have been rude in any way I'd like to know about it so I can monitor it in the future. One's on-line presence is often a poor reflection of one's personality.

 

[Braunbehrens]

Charlie99 once bubbled...
What I do know about deco might surprise you.

Einstein was once giving a speech in front of a group of housewives. At one point, one of them asked him if he could explain the theory of relativity. Before answering, he asked the woman if she could explain to him how to make a cake. She said yes, she could. He then asked if she could explain to him how to make a cake if he didn't know what an egg is.

My point is not that you, Charlie, don't know anything about deco, or that I'm a genius - I'm not. My point is that this stuff gets archived, and anyone can read it. I'd have to start explaining all kinds of stuff just to get to the good bits. It's just not reasonable to ask me to do this on an internet forum. I am not an instructor, I am not an authority on deco, and what works for me might not work for you.

I have given you the pencils, the rulers and the aerial photographs, but you guys keep asking me to draw the map. I can't and don't want that responsibility. Draw your own map.

I use basic set of rules and a few tables and this covers all my diving. It's all very very simple. Deco is not an exact science. It works for me.

I won't give you my cheat book, but if you have specific questions I'd be happy to answer them to best of my ability. I am NOT an authority on this, just a guy who took a class and did a little (not a lot) of reading.

 

[Charlie99]

Braunbehrens once bubbled...
I won't give you my cheat book, but if you have specific questions I'd be happy to answer them to best of my ability. I am NOT an authority on this, just a guy who took a class and did a little (not a lot) of reading.

1. Does your method keep you within NDL at all times, or does it simply clear your deco obligation by the time you get out of the water?

2. Have you used your method with single gas, multilevel, repetitive NDL diving of 3 or more dives per day?

3. What is your objection to having an independent calculation (by the computer) of NDL and tissue loading, with which you can compare your mental on-th-fly calculations?(this is in the context of single tank, single gas NDL diving)

The above 3 questions should not require you to put info onto the web that might be dangerous.

Charlie

 

[Diver0001]

Braunbehrens once bubbled...
Mike, you are dead on!

The rest of you guys are pretty funny. I give a DETAILED account of how to proceed, but you want everything served up on a silver platter. Give me a break!

Give ME a break. I ask you a question about dive planning and you answre me with some kind of absurd story about hiking in the woods and drinking water. You played the " knowledge is power " card and lost my respect. I would *never* take a course from an instructor who plays the "knowledge is power" card. No sane individual would.


This is EXACTLY why I'm not going to serve it up. You don't want to take the time to understand why these rules apply, you just want to know what they are. That's just how you get hurt.


what a crock. Why the hell do you think people ask these questions? The fact that you can't seem to answer that says more, much much more about you than the people asking the question. And don't get me wrong (to use your own words) we don't think you're an arrogant SOB. <big smile>

how on earth are you *ever* going to get people to take DIR seriously when you act like this? I actually gave you the benefit of the doubt. My mistake.


Ironically, that is also what you guys always criticize about DIR. "You guys just blindly follow what Trey says..."


NO, people believe this because Trey only leaves room for obedience. If he told you the moon was made of cheese you'd teach it to everyone. That's one thing that PADI does much much beter than GUE. At least the things PADI says are based in fact and supported by scientific study. All you have to go on is "Trey says so". Don't belive me? Remember the artical on deco procedure he wrote when he said (quote is approxmiate) "if you want to refute me then you'd better show me your log book because I've done this more often and better than anyone else and I won't believe anyone unless your log book can convince me".

Nice clean scientific underpinnings there.

Add to that, the GUE's obsession with supressing information about incidents among their members and you're starting to raise some major question marks in Rob's mind.

Remember JJ's letter about Steve Berman? Steve wasn't GUE but JJ was willing to essentially pubicly walk over the bones of his dead friend to protect the GUE. it was totally unnecessary aside from tasteless and immoral. Anyone who cared already knew that Berman was TDI. How did you read that? The way the rest of the world did or the way JJ told you to?

And if you didn't conform you wouldn't be a GUE instructor. Full stop.


Well, I'm sorry to disappoint you, I don't blindly follow anyone, and I'm not going to make it easy for anyone else either.


Of course you do. Where do you keep your reel? On the butt D-ring? I suspect that you *used* to do but these days you keep it somewhere else. Where might that be? Maybe I should ask George. He'll know. And if he changes it again I know who will fall in line......


deco without a computer? Then LEARN about deco. You don't have to take a GUE class to do it, just talk to some people (like Trey, or MHK, or Dr. Deco), and/or read some of the research, use some common sense, take a look at some deco programs and do some dives.


It's all *so* dangerous that you can't even explain it but now your're saying "just go do some dives". You know what this reminds me of? Martial arts. In the 70s they had "magic moves" and "secret techniques", "finger of death" etc etc that were *SO* dangerous that you couldn't learn about them until you took a bunch of classes and paid them a whole sh*t load of money. Well. I sucked into it. I took 10 years of classes and I can tell you there *IS* no "finger of death". This B.S. that you're spouting now has a very familiar taste to me.

<snip>

Remember also that we use a limited number of gasses. You will never learn anything if you continually use a hundred different gasses. If you stick to a couple bottom mixes and a couple deco mixes everything clears up.


Ok. now we're talking. pull the skirt up a little higher.


The problem is that all this stuff hangs together. You can use this small part and that small part, but in the end you can't be sure that the whole system works, unless it's been tried out. I know of only one such system that has been extensively tried out.


Got that right. The only system that has been tried out extensively would be the Padi system


I don't know why I even bother....and people say the DIR crowd is unfriendly! I should put together a collection of the replies I get from the non-DIR people.


Perhaps looking into the reasons why you seem to evoke these reactions wouldn't be going too far either.


Try to keep it friendly please. We are all just divers trying to have fun...

I'm having trouble beliving you at this point. I suspect that your posts on Quest are much less sympathetic to your friends on scubaboard than you attempt to portray here.

R..