The Octopus Conundrum

[MXGratefulDiver]

This is getting a bit far afield of the intent of the thread ... but to a degree I can see oldschoolto's point. There's a difference between fundamental skills and optimization ... or between the importance of equipment choices depending on the environment in which you're diving. Choosing equipment for streamlining can impact your dive significantly or negligibly depending on dive conditions and which gear you're talking about. Diving in proper trim on the other hand can have significant impacts on both your comfort and air consumption regardless of diving conditions ... which is why it's a fundamental skill. Sometimes I think we overemphasize the small things while overlooking the ones that really matter ... to dive or not with an octopus, to my concern, falls within the former category ...

... Bob (Grateful Diver)

 

[Eric Sedletzky]

This whole idea with "trim" is completely hilarious to me.
I'm not an aircraft, I'm not a marine vessel either surface or sub,
I'm a living breathing mammal that can move, twist, turn.
The whole notion of trim and how it's described is so mechanical and non dynamic.
I don't see Dolphins, whales, or seals/sea lions too worried about "perfect trim".
In my world I want to be more like them not a submarine.
I could see perfect trim possibly in a wreck or a cave: go in flat, stay flat, see a passage above, elevator up - still flat, go in, see another passage low - elevator down staying flat, go forth, etc.
But diving in the kelp forests and the rocky terrain of Northern California? Rediculous.
I orient my body towards the direction of travel and conform myself to the terrain and the surroundings.
I don't dive like I'm tied to a board that only sits level.

 

[lemke]

As a spearfisher, I have punched myself square in the regulator with the recoil of my gun. I have an Air2 or a bungied reg around my neck.

 

[MXGratefulDiver]

This whole idea with "trim" is completely hilarious to me.
I'm not an aircraft, I'm not a marine vessel either surface or sub,
I'm a living breathing mammal that can move, twist, turn.
The whole notion of trim and how it's described is so mechanical and non dynamic.
I don't see Dolphins, whales, or seals/sea lions too worried about "perfect trim".
In my world I want to be more like them not a submarine.
I could see perfect trim possibly in a wreck or a cave: go in flat, stay flat, see a passage above, elevator up - still flat, go in, see another passage low - elevator down staying flat, go forth, etc.
But diving in the kelp forests and the rocky terrain of Northern California? Rediculous.
I orient my body towards the direction of travel and conform myself to the terrain and the surroundings.
I don't dive like I'm tied to a board that only sits level.

Neither do I, but there's a difference between trim and orientation ... and it really boils down to what you're doing in the water at the time. Simple physics dictates that pushing more water out of the way as you pass through it requires you to work harder, which in turn causes you to breathe harder and consume your air faster. Why would you want to do that?

Trim isn't about what position you're in when you're sitting still ... it's about your orientation when you're moving through the water. If you're vertical or diagonal to the direction of travel, you're pushing more water than you have to. You're also ... by necessity ... negatively buoyant.

If you want to dive like that, go nuts. It won't kill you ... but it will make you inefficient.

But that wasn't really my point in bringing it up. My issue was with the statement that a "good instructor" won't teach while in proper trim, because they can't see or react. That's a ridiculous statement ... as anyone who's actually tried it can attest. A good instructor demonstrates competence and efficient technique because students tend to copy what they see, and if an instructor can't set a good example by diving with some reasonable level of competence, then they shouldn't be teaching ...

... Bob (Grateful Diver)

 

[danvolker]

I think the issue of contention is the belief of some divers, that good trim means you are always flat horizontal.

The problem with this, is that if you want to swim down
to, or up to something that is at 45 degrees to you ( an angle), the BEST way to swim to it is to orient your body on a plane that connects with your target...so instead of being flat horizontal, your body may be at a 45 degree angle pointing down and forward, but "flat" in the vector path to your target...this is the least body drag, and the fastest and most efficient way to swim to the objective.

This is what a dolphin would do..or a freediver, and it is certainly what I would do.

When I am swimming 6 inches off the bottom, going up current and using skin fiction drag of the bottom to negate current...I am staying in flat horizontal trim....for the same reason

---------- Post added April 9th, 2015 at 01:43 PM ----------

An area I would love to hear Bob expound on...so that I could borrow some of his ideas for my next chats with some of my friends that are PADI instructors....is exactly the way a good instructor can manage to teach a class in ideal trim.

My guess, is that the errant mindset is that students shooting up and falling like rockets at 4th of July, forces the instructor to be vertical to maintain sufficient visual contact with all the vertical movement of students.....and that when you are in flat horizontal trim, most divers can only see up maybe 20 to 30 degrees or so---and could be missing a student now 10 feet above them, and 10 feet in front of them.

I assume Bob will have a plan to prevent the shooting up and down....that this is prevented from ever happening. And that students will have buoyancy control prior to being in a depth where they could shoot out of the visual range of the instructor. This is a shallow pool session, where buoyancy control is harder than it is at 20 feet deep.

I would also suggest that even with an instructor at flat horizontal trim, watching students in flat trim--should one blast vertical, the instructor can re-orient his body to be vertical in an instant, if required.

So Bob, what's your secret ?
And what do you say to the instructors that have been conditioned to believe that the only safe way to teach a class, is vertical body position ( standing) ?

 

[Akimbo]

I have always sought balance so I could be in, and maintain, any attitude in the water. That was never drilled into us; it is just the most comfortable. I don’t understand how people can say they aren’t over weighted but can sink feet first to the bottom. I also don’t get those that stay nearly horizontal when descending. How do they ever hit a target on the bottom without a downline? I am head-first in whatever direction I am traveling, even descending in a drysuit. I vent off more gas if the drysuit is too baggy and suffer the minor squeeze.

I suppose that is one of the advantages of learning freediving first. It is much easier to achieve that balance than on Scuba. Once you experience it, you don’t want to give it up. I try to put my center of gravity in the water near my spine about belly-button level on Scuba and about center mass at diaphragm level Freediving.

 

[MXGratefulDiver]

An area I would love to hear Bob expound on...so that I could borrow some of his ideas for my next chats with some of my friends that are PADI instructors....is exactly the way a good instructor can manage to teach a class in ideal trim.

My guess, is that the errant mindset is that students shooting up and falling like rockets at 4th of July, forces the instructor to be vertical to maintain sufficient visual contact with all the vertical movement of students.....and that when you are in flat horizontal trim, most divers can only see up maybe 20 to 30 degrees or so---and could be missing a student now 10 feet above them, and 10 feet in front of them.

I assume Bob will have a plan to prevent the shooting up and down....that this is prevented from ever happening. And that students will have buoyancy control prior to being in a depth where they could shoot out of the visual range of the instructor. This is a shallow pool session, where buoyancy control is harder than it is at 20 feet deep.

I would also suggest that even with an instructor at flat horizontal trim, watching students in flat trim--should one blast vertical, the instructor can re-orient his body to be vertical in an instant, if required.

So Bob, what's your secret ?
And what do you say to the instructors that have been conditioned to believe that the only safe way to teach a class, is vertical body position ( standing) ?

First step ... stop teaching your students while they're vertical ... which is exactly what putting them on their knees does. I start mine out laying in the bottom of the pool, get them first into a fin pivot position, then have them lift up their fins and do things while horizontal. If you begin that way, it's not that hard. And if they're not vertical themselves, the chances of them "shooting" to the surface are essentially nil. They might drift up a bit, but an errant fin kick isn't going to send them upward.

Second step ... teach them proper buoyancy control in the pool. Having a student mimic a pool demo isn't "mastery" ... and they need sufficient time to practice repetitively. Getting comfortable with buoyancy in the pool is a good first step, and teaches them how to respond to changes in depth ... so you won't have to "chase" them in OW.

Third ... demo all skills in proper trim, and while hovering. Students will do what they see you doing ... and if you start them out that way they'll usually surprise you with how well they can do it (because you haven't ingrained in them the notion that it's somehow hard to do).

FWIW - I learned all of the above while working with a guy who was both a PADI and SSI instructor. The only time he ever had his students on their knees was on their initial descent in the shallow end while breathing on a regulator. As of the second descent and through the rest of the class they were either hovering or just touching their fin tips on the bottom (fin pivot position). The guy's been teaching classes that way for more than three decades.

And FWIW - some of his exercises involve putting students in various orientations while maintaining neutral buoyancy. I've seen OW students of his doing headstands while hovering a foot off the bottom. He's not training "boards" ... he's teaching them how to develop good fundamental technique ...

... Bob (Grateful Diver)

---------- Post added April 9th, 2015 at 11:45 AM ----------

I am head-first in whatever direction I am traveling,

... that is proper trim ... at least if the goal is the most efficient way to get there ...

... Bob (Grateful Diver)

 

[Eric Sedletzky]

Neither do I, but there's a difference between trim and orientation ... and it really boils down to what you're doing in the water at the time. Simple physics dictates that pushing more water out of the way as you pass through it requires you to work harder, which in turn causes you to breathe harder and consume your air faster. Why would you want to do that?

Trim isn't about what position you're in when you're sitting still ... it's about your orientation when you're moving through the water. If you're vertical or diagonal to the direction of travel, you're pushing more water than you have to. You're also ... by necessity ... negatively buoyant.

If you want to dive like that, go nuts. It won't kill you ... but it will make you inefficient.

But that wasn't really my point in bringing it up. My issue was with the statement that a "good instructor" won't teach while in proper trim, because they can't see or react. That's a ridiculous statement ... as anyone who's actually tried it can attest. A good instructor demonstrates competence and efficient technique because students tend to copy what they see, and if an instructor can't set a good example by diving with some reasonable level of competence, then they shouldn't be teaching ...

... Bob (Grateful Diver)

I think you misunderstood or misread what I was saying.
I DON'T orient myself at a 45 degree angle to the direction of travel, that's exactly what I don't do, and what I always rail against.
My personal philosophy is that the most effective position to be in is pointed towards the direction of travel, where your're going to make the smallest "hole" you can as you move forward creating the least amount of drag. This changing orientation is dynamic.
Somebody who only stays flat like in a skydiver position the entire dive and uses a wing to ascend and descend like an "elevator" is static orientation. This is what was always explained to me as "proper trim". I know a guy who didn't pass fundies because he got out of trim during a valve drill in the pool. So in this case "perfect trim" meant flat, as in put a level on him and look at the bubble.
I use the dynamic method.
Like many put it "like a freediver", which I am.
Just to clear things up.

 

[DaleC]

Somebody who only stays flat like in a skydiver position the entire dive and uses a wing to ascend and descend like an "elevator" is static orientation. This is what was always explained to me as "proper trim". I know a guy who didn't pass fundies because he got out of trim during a valve drill in the pool. So in this case "perfect trim" meant flat, as in put a level on him and look at the bubble.

I don't know about that.

In fundies there are different levels of allowance, depending on a rec pass or a tech pass. If one is doing a valve drill for example, in the horizontal position (because that is the orientation of choice for that activity) one should be able to maintain that orientation while doing the drill. If you lose control of your orientation because you are too task loaded by the drill I think most would agree you should not receive a tech pass.

With a rec pass you are allowed quite a bit more leeway.

You do the drills in a horizontal position because you are facing each other, observing the drill. Being horizontal you can maintain distance by using forward, backward and helicopter kicks. How would you maintain distance if drills were done vertically?

 

[danvolker]

I don't know about that.

In fundies there are different levels of allowance, depending on a rec pass or a tech pass. If one is doing a valve drill for example, in the horizontal position (because that is the orientation of choice for that activity) one should be able to maintain that orientation while doing the drill. If you lose control of your orientation because you are too task loaded by the drill I think most would agree you should not receive a tech pass.

With a rec pass you are allowed quite a bit more leeway.

You do the drills in a horizontal position because you are facing each other, observing the drill. Being horizontal you can maintain distance by using forward, backward and helicopter kicks. How would you maintain distance if drills were done vertically?

Dale, that is not the gripe being discussed....that is common sense.
The issue would be body orientation while swimming and going up or down. Its about drag and effectiveness for getting to a spot quickly and efficiently.
However, I don't know of any GUE mandate that prevents a diver from pointing down straight to bottom if that is the need to reach a point effectively--or to use a 45 degree up angle to get to the side of a ship, and to have the body at this angle.
What we may be seeing, is "some" GUE's, that have gone overboard trying to appear to be in trim--to "look pretty", but have forgotten about the real objective.

It's just "some" though, because I have dived with plenty of GUE divers that are excellent in the water, and that don't do the nonsense.


As a tangent....the BEST diver I have ever dived with in my life, George Irvine, began as a spear fisherman.....then became WKPP trained by Parker Turner, and ultimately derived DIR from all his experiences and the wealth of great diving talent around him......And while George was ocean tech diving with us during our big DIR push in late 90's, his trim was what Eric and I are talking about.....he would point where he would go , but be flat when it was best to be flat. Whatever was BEST for the spot he was in. Trim was a tool.