DIRF, A Sobering Experience

[O-ring]

FYI, for those of you taking the DIRFund class this weekend in Raleigh NC, word is JJ himself is teaching it. Presumably the guy who wrote the book is a pretty good instructor - should be fun.

JJ and MHK are teaching it...I think there are 10-12 in our class. Looking forward to it..

 

[Rick L]

Hi
Iv'e been reading lots of dir type discussions of late.
My question is: Is it still fun and enjoyable to dive?
It almost makes every part of diving sound like work?
Or is there difference in the type of dir diving you are doing(rec deep cave wreck?)Or do you keep the same mental attatude
no matter what you are doing in the water? Or is it that you get so used to doing all the prep stuff that it becomes 2nd nature to you?
Rick L

 

[JamesK]

Now, I have yet to go through a DIR class, but I do adopt many of their philosophies. So take my answer with a grain of salt.

Originally posted by Rick L
Hi
Iv'e been reading lots of dir type discussions of late.
My question is: Is it still fun and enjoyable to dive?
It almost makes every part of diving sound like work?
Or is there difference in the type of dir diving you are doing(rec deep cave wreck?)Or do you keep the same mental attatude
no matter what you are doing in the water? Or is it that you get so used to doing all the prep stuff that it becomes 2nd nature to you?
Rick L

Yes, it is still fun to dive. Every dive should be fun in one way or another.

It is work. If you do not work at it, you do not get better.

It does depend on the type of diving I am doing. If I am doing a cave dive, obviously my dive plan is a lot different than if I am doing a 45 foot reef dive.

I do keep the same mental attitude though, no matter how routine or simple the dive.

Yes, the stuff becomes second nature very quickly actually.

 

[VTWarrenG]

Neil,

Strangely enough, the failure rate of some of my high-level engineering and physics courses in college was very close to 50% -- yet the professors and the University were still highly praised.

- Warren

 

[roakey]

Originally posted by MikeFerrara
If you are trimmed correctly you will be able to maintain any position desired. A fin pivot is more dificult for some when trimmed correctly but it can be done.

Roakey, To prove it to yourself pretend you are ascending up out of Olsen Sink. If you can't maintain any position other than horizantal you won't fit. The main benefit of proper trim is the ability to maintain any position desired with minimal effort. How do you teach buoyancy control?

I think we’re mostly in agreement here. There’s a world of difference between being able to maintain an orientation and a fin pivot. I can pitch up or down and maintain that pitch because my center of gravity is more or less in the same position, front-to-back and side-to-side, as my center of buoyancy.

This is quite different than a fin pivot, that requires your CoB to be forward of your CoG in order to work. You’re right, you can do it, off the top of my head when wearing a drysuit I could probably stick my arms straight out in front of me to move my CoB forward and accomplish a pivot, but this is neither a natural position nor a desirable behavior. A pivot is a simplification of a more complex behavior and as such can be a useful tool, but I don’t think most instructors see it that way. PADI doesn’t even have a clue as to what correct horizontal trim is! I’ll address this in my next post.

Where I disagree with your claim “A fin pivot is more dificult for some when trimmed correctly but it can be done.” Is that holding all variables the same except for breathing, you can’t rise horizontally off the bottom on one breath and do a pivot on the next, you need to change *something* in order to accomplish a shift in the CoG or CoB.

Roak

 

[JamesK]

A fin pivot is impossible when you have your knees bent at 90degrees behind you going straight up. hehehe.

 

[roakey]

Originally posted by CincyDiver
This skill [a fin pivot] has nothing to do with trim. This falls under establishing neutral bouyancy.

The fin pivot is to assist in establishing neutral buoyancy, but the fact that you can do it has EVERYTHING to do with trim. This is my point. You have to be trimmed wrong in order to do it.

Originally posted by CincyDiver
This information is straight from the PADI instructor manual. The next step after establishing neutral bouyancy is the neutral buoyancy swim. And I quote, "Emphasize that they're simulating swimming over a reef and that they must avoid contact with the bottom or sides." I won't disagree that there are bad instructors out there who don't point this out to their students. You have to start someplace and this is their first baby step of controlling buoyancy with their lungs.

Absolutely wonderful quote! And from the instructor manual no less! A perfect example of what PADI is teaching wrong. Swimming? You can overcome all sorts of poor, let’s call it “static” trim if you’re swimming! While swimming you can supply a downward vector to keep your “heavy” legs off the bottom. Dynamic trim is easy, but tiring, since you HAVE to swim in order to maintain horizontal trim. Now STOP swimming and see what happens: Your legs drop down on the bottom. Your trim when swimming has zippo to do with your static trim. But, thanks to your quote we all know that’s what PADI is teaching. Just ducky.

Originally posted by CincyDiver
I'm sorry but this makes no sense. I keep a horizontal attitude in the water, yet I can do a fin pivot. These are two separate things. See MikeFerrara's posts above.

It makes perfect sense. You’re PADI trained. You don’t know what you don’t know. You think that swimming trim is what’s important and it’s not, it’s static trim. This is how you keep a horizontal attitude in the water and still do a fin pivot. You’re comparing your dynamic, swimming trim to your static, fin pivot trim. As for Mike’s post, please read my reply above.

Originally posted by CincyDiver
I totally agree that horizontal trim is a skill for everyone. If your instructor does not teach this, find a new instructor.

So, are you? Maybe even a new agency?

There’s a even more to this, as well as an exercise to develop better buoyancy control and horizontal static trim in http://www.scubaboard.com/t8232/s.html, I suggest interested folks go read that note.

Roak

 

[large_diver]

Roak......that link leads to the main scubaboard page.......

 

[Lost Yooper]

That's exactly right, Roak. That's almost word for word what they were talking about this weekend. Weighting and harness/tank placement is critical in achieving this proper trim. Almost everyone was considerably overweighted this weekend and thereby couldn't have gotten it if they wanted to for that reason alone. In fact, Andrew was complaining of back spasms from arching because he was slightly overweighted!

Mike

 

[roakey]

OK, this is right off the top of my head but I’ll throw it out for discussion anyway. Us DIR zealots talk about “gliding” with the rig. We usually point to the hydrodynamics of the rig as to the reason we can glide like we do. Not to downplay the rig, but I think a lot of it has to do with trim too. Having correct static trim allows you all the time in the world between kicks, unlike correct dynamic trim. I can kick, glide forward, look around, check on my buddy, come to a complete stop, check my gas, futz about and then simply kick again and I’m off.

If you only have correct dynamic trim, when you slow down and stop your legs sink. Your next kick has to accomplish two things, it’s got to get your legs up again AND propel you forward. So a good portion of your kick and therefore your energy is wasted in just maintaining correct trim. Your only other option is to not stop kicking in order to keep your trim flat. Then you end up looking like my puppy out for a walk, zipping back and forth and expending huge amounts of energy and, as a side effect, consuming huge amounts of gas.

Thoughts?

Roak