Why no computers for DIR?

[Kendall Raine]

I appreciate your analysis, Charlie, and agree with some of it. In particular, I agree the choice of "Baker's Dozen" cheapens the argument by forcing articulation of flimsy points in with more robust ones. Rather than debating point by point, however, I'll suggest JJ isn't saying people who use computers are idiots. Far from it. I think he's saying that getting rid of the computer is intellectually and operationally liberating. I think his goal is to encourage divers to develop a truly intuitive sense for decompression and what works for them. In so doing, the computer evoloves from tool to hindrance. As in my previous post, much is imbedded in context and perspective. From my own experience, dumping a computer in multilevel multidive situations took time and a weaning process. Precedents in my case included a decade long technical diving background, fascination with learning about how decompression works and regular use of a Doppler. To expect others to uniformally follow that path is unrealistic. Certainly value judgements along that plane are foolish.

Rather than distinguishing between those who view recreational diving as an exciting activity in its own right versus simply a stepping stone to technical diving, I prefer to see the distinction as between those who enjoy the "technical" aspects (physiology/physics) of diving, regardless of time/depth issues, versus those for whom the physiology and physics hold little allure. Not everyone approaches diving the same way or seeks the same things from it. I honestly think JJ would agree with that. He doesn't strike me as someone out to colonize the world.

Best regards,

Kendall

 

[Charlie99]

Kendall Raine once bubbled...
Rather than debating point by point, however, I'll suggest JJ isn't saying people who use computers are idiots. Far from it. I think he's saying that getting rid of the computer is intellectually and operationally liberating. I think his goal is to encourage divers to develop a truly intuitive sense for decompression and what works for them. In so doing, the computer evoloves from tool to hindrance. As in my previous post, much is imbedded in context and perspective. From my own experience, dumping a computer in multilevel multidive situations took time and a weaning process. Precedents in my case included a decade long technical diving background, fascination with learning about how decompression works and regular use of a Doppler. To expect others to uniformally follow that path is unrealistic. Certainly value judgements along that plane are foolish.

Both your statements above, and much of what JJ says in the DIR-F book are reasonable statements that I agree with. I didn't really mean to imply that JJ calls computer users idiots --- he clearly makes a conscious effort to avoid that sort inflammatory language.

In the sentence just before introducing the Baker's Dozen list in DIR-F book, JJ says "Divers that choose to use computers should do so after becoming well-versed in diving limits and then using the computer primarily as an educational tool". While this is not 100% congruent with my thoughts, it's pretty darn close.

One frustration that I have expressed before on both Scubaboard and other internet venues is that, while various DIR advocates decry the use of computers, that there is very little information available about reasonable alternatives. While divers are repeatedly encouraged to "compute NDL on the fly", nothing concrete about the method is presented. Most definitely nothing gets presented about workable methods in multi-level repetitive dives ---- exactly the sort of diving that is both common recreationally, and where a computer has the greatest advantages over simple square profile tables. The most reasonable alternative I have seen so far is the PADI wheel --- or the flat table equivalent that I have generated using the same basic Spencer M-values.

So in one sense, I see the DIR position as one that decries the use of computers, but at the same time it fails to offer up any viable alternatives.

It would be useful for you to describe in more detail your multilevel multidive protocols / calculations.

--------------------------------------------------------------------------------

The whole thing boils down to a philosophical argument about what is improper dependence upon a crutch, versus effective, rational use of a tool.

I use the timer of a computer instead of counting one-one thousand, two one-thousand, etc.

I use the depth measurement of the computer instead of using my eyes to measure depth. I rely upon them, but at the same time I do various cross checks and sanity checks on what they are telling me.

I choose to treat a computer in much the same way on deco calculations. It does its calculations. I do mine. I compare the two -- and here is where we probably diverge --- if the computer calculation is in the right general ballpark, I treat it as more reliable than my crude approximations.

Charlie Allen

p.s. I have developed a series of tables upon which I can plan arbitrary deco dives, including stops, using neither an underwater computer, NOR the above water PC or Palm computer upon which many rely ---- but I don't criticisze those that choose to rely upon computer-based programs such as Decoplanner or VPM.

 

[Uncle Pug]

BigJetDriver69 once bubbled...
And, yes, I have a feeling I know where you'll be going with that last comment! =-)

 

[Kendall Raine]

I'd be happy to explain how I do it. There's no mystery and certainly nothing proprietary about the process. However, it's late and I need to get up early for what will be a busy day tomorrow, so I hope it's OK if I write in detail on Friday.

Kendall

 

[jonnythan]

caveman once bubbled...
Massive lol........ lets takea parallel ( from my industry - Aeronautics ).

Lets strip out all of the Autopilots, Inertial Navigations systems and what ever, and go back to the days of the Wright Brothers and Leanardo DaVinci. Yes, modern aircraft rely on alot of electronics...... but lets do a test:-

Let a pilot fly a 12 hour trip i.e. in manual mode and another using auto pilot, and just before landing let and engine catch fire. I would bet u hands down the autopilot guy would be more up to the task and the manual guys would be totally wasted.

No way, the guy who flies manually all the time is going to be all over the malfunction since he has so much more experience with manual flying. The guy who lets the plane fly for him or just does what the computers say is definitely going to be at a disadvantage.

 

[chrpai]

jonnythan once bubbled...


No way, the guy who flies manually all the time is going to be all over the malfunction since he has so much more experience with manual flying. The guy who lets the plane fly for him or just does what the computers say is definitely going to be at a disadvantage.

You are so wrong its not even funny. Just what do you think the pilots are doing on a plane while its on autopilot? You REALLY think they are sitting there saying:

"Wow this is so neat, it just flys itself. I wish I understood how it works."

No, they are sitting there handeling the com, scanning for traffic, monitoring all the instruments for anything wrong and constantly planning for what might happen next. And when the **** does hit the fan they have practiced their procedures so much that they know how to manage the emergency. So much work has gone into cockpit resource management that it makes DIR looks like a joke.

When an emergency happens they know how to handle it and they know rule #1. ALWAYS FLY THE PLANE.

If you don't believe me ask BigJets.

 

[BigJetDriver]

jonnythan once bubbled...


No way, the guy who flies manually all the time is going to be all over the malfunction since he has so much more experience with manual flying. The guy who lets the plane fly for him or just does what the computers say is definitely going to be at a disadvantage.

:wacko: Sorry, Jonnythan, but you are completely wrong on this one!

I do not know if you are a pilot.

I have been a professional aviator for over 30 years, and a pilot of high performance, large jet aircraft for over 18 of those years. You will, I think, just have to trust me on this one.

This is the way the industry has learned to deal with emergencies, based on research largely sponsored by NASA's Ames Flight Research Center.

The key to proper response in an emergency is:

(1) Avigate

(2) Navigate

(3) Communicate

We do any "Immediate Action" items first, and then take a moment to assess the situation. It's our version of:

(1) Stop

(2) Breathe

(3) Think

(4) Act

If the computer is available, and the autopilot is functioning, we utilize BOTH to reduce our task-loading. This definitely, as Kendall Raine likes to say: "Saves bandwidth in the brain!"

That bandwidth is extremely necessary because BOTH pilots are multi-tasking like crazy at this point. (Having two pilots working on the solution to the problem is a definite advantage over the diver who must solve his or her crisis alone.)

NASA's research has shown that, when the brown stuff hits the rotating device, task-loading tends to narrow one's judgemental focus and capability. Using a device, such as the computer / autopilot reduces that task-loading, and gives one time to think out the problem, and act in measured response. NASA's research has shown that there are fewer mistakes made that way.

I, personally, do not like mistakes in the flight regime, especially in an emergency situation. Remember, I sit in the pointy end. If anything happens, I get to the accident scene first! To me, this is NOT GOOD!

Now, if I may take a moment to counter a couple of other popular misconceptions:

(1) Contrary to popular belief, we don't just ride around shooting the bull and drinking coffee when the autopilot is performing the mechanics of flying. We remain "in the loop" constantly to assure that "George" is going where we want to go, where we TOLD him to go, and where we need to be! Note the thought process here. "George" does NOT tell us where to go. We tell HIM where to go!

(2) Also, contrary to popular belief, we do quite a bit of "hand flying" so that our "hand-eye" coordination remains sharp. Typically, we fly from take-off to altitude, and from altitude to touchdown, unless we are doing a minimum visibilty approach. We leave the boring, straight and level trim adjustments while in cruise to "George" to reduce fatigue levels. As NASA has pointed out, this helps to keep mental acuity levels up where they need to be in the critical phases of flight.

(3) Our computers do NOT make the decisions for us. They do, however, give us MUCH more information, and increase our situational awareness (SA) WONDERFULLY. Having done flying from the most basic, bare-bones way to the most modern, let me assure you that this increase in SA is "PURE EFFING MAGIC"!!

(4) As I keep trying to tell folks:...CDRYB / LOUD...!!! (Computers Don't Rot Your Brain / Lack Of Use DOES)...If you use the computers to EXPAND the performance of your brain, then, according to NASA, you are TRULY...Doing It....(Sorry, almost couldn't resist that one!) :doctor:

 

[cavemanxxx]

Scotty

Agreed, lets keep it civil ( I felt that yours was not so civil as well, but never mind ).

Recon BigJetdriver has done a good write up ! . If safety is so important for DIR divers, then how about a dive computer + a bottom timer !. Wow, then you got redundant systems and one also if your brain fails.

"task loading, then U should not be under water", sorry, but you fail to understand the mechanics of human factors engineering and reliability engineering. If you do some research you will find that BigJet is right that computers can help off load menial tasks and save important brain power for when its needed. When an emergency presents it self, the less task you have, and the more u can focus on the emergency at hand, the more chance of survival ( Fact - read up on the HFR factors in cockpit design, its a science ! ). Pilots dont take them selves out of the loop as you are suggesting, and keep a mental track of whats going on, all be it at a more relaxed level.

Sorry, I have been heavily involved machine redundancy/ reliability and human factors engineering / physiology etc and this thing about lets go back to the stone age ( read:- DIR ) does not fly.

Again, if U are really keen on your safety as you say, then use a bottom timer and depth guage, do your mental calculations, stay in the loop, and have an 'independtant observer' ( read: diver computer" ) and a back up 'person ' to consult with.


THATS REAL DIR !! ( not DIW )

 

[ScottyK]

My apologies to you as wall if you felt my post was a little
"rough around the edges"

Again, I believe both ways of doing it are perfectly acceptable, and there is room for personal preference. My main concern with your position that not using one adds signifcantly to task loading, and is "stone aged". Kind of the mirror image of Charlie99's complaint that the anti computer camp and their brian rotting theories. I believe the truth lies somewhare in the middle.

In the spirit of getting this back on topic, let me ask you something. Have you ever tried doing it without the computer? I don't mean the ten dives between the time you got your OW, and your first computer purchase Have you ever ditched it, and spent say at least 20 consecutive dives doing the five minute checks with only your knowledge of the tables and a bottom timer?

If you haven't, you should try it before you knock it, and if you have I'd be interested to hear what your experiences were.

I found that after about ten dives or so, my situational awareness became sharper, and the more structured approach didn't add to my task loading. I barely noticed I was doing it. Of course, every one is different, and your mileage may vary. I just didn't really seem to need the computer anymore. It's still on my wrist. I just use it as a bottom timer now.

 

[cavemanxxx]

Thanks for the positive comments. Confession, nope I rarely look at tables these days, do dive with 2 dive computers. One reason is for redundancy, second is i do long live aboard trips, and if one goes bung, i got still my profile.

I am heavy into underwater photography ( 2x Macro ) and dont really do deep stuf, and the name of the game for me is max time. A dive may last normally for 1.5 hours + on a single tank, starting at about 20m, and and slowly working up to about 5 where i will be for yonks looking for shots. After 9 years and approx 900 dives ( yeh, i kow there are guys with 10,000 + ) , i kinda know what the results will be, and generally dont like going or staying deep.... does not give me any pleasure, and the best photo's are often between 15 - 5 m


My comp gives me the felxibilty to deviate from a pre-defined plan. For example, in burma we found a neat seahorse at 24m, which I stayed with wayyyy tooo long. ( agreed, big no no...but hey, it was a once in a 7 year shot ! ...which i still managed to screw up ) ..... dive comps accounted for the deviation from plan and bought me back in one piece. ( 12 mins into deco...hung around for 30 mins at 5 meters to be sure as we were a day away from port.... p.s. was not surprised, and made a concience decision to go into deco as i dive with a pony and know my RMV's ..this was a rare case, i rarely approach deco on long trips )

Agreed, the thought of putting my life in the hands in someone elses is scary, but then again we do it every day........ the guy who made ur timer or depth guage may of made a mistake. So it dont matter how good your table is, if the timer leaks or is slow, you may also end up in trouble............


, the guy who made your reg may of screwed up etc etc...... and if you dive with a buddy, you may need to trust him / her.

At the end of the day self reliance is important, but having trust is something which we cannot get around.