Apparently hovering is physically impossible

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That's why we have adjustable bladder (BCD) and fins like fish. And brain better than fish. Even fish fins are always moving while hovering. And practice makes perfect.
 
If your instructor told you to be perfectly stable at the same depth, you should have strong words with him/her. I've never met anyone teaching that.

In comparison, the standard for the Fundamentals of Diving course for GUE (which is rigorous, regardless of what else you think of them) states a passing grade for the Recreational rating requires "a maximum of 30 degrees off horizontal while remaining within 5 feet/1.5 meters of a target depth" and for Technical rating is "a maximum of 20 degrees off horizontal while remaining within 3 feet/1 meter of a target depth." So that's up and down off the target depth by 2.5 feet for the lenient standard and 1.5 feet for the more demanding certification. That's while doing required skills, e.g. removing your mask and putting it back on, deploying a DSMB to the surface on a spool, etc.

Note that a horizontal orientation helps tremendously as the broad/flat part of your body resists up and down bouncing. A diver who is overweighted and has their feet pointed downward will yo-yo greatly, sinking when they stop finning and rising as they overcompensate by adding air to the BC. It's one reason why people on ScubaBoard tend to sound a bit fanatical when talking about proper weighting.

I generally aim for my buoyancy to be "neutral" when my lungs are about 60% full, so regular full breathing keep me in a very narrow depth window, as in so narrow that I can be right next to something during a relaxing recreational dive and never worry about making contact. Of course if you're sticking your face next to something to get a good look or veering over an obstacle, you'll likely alter your breathing. Those will become unconscious adjustments as you do more diving.
 
There are a number of phases to buoyancy development. These phases occur over thousands of hours in-water. They are not distinct phases, but a gradual transition.

The first phase is of conscious adjustment. The diver focuses on their breathing, their BCD inflation, their leg and arm movements, their posture in the water. There's a lot of variables to track and control. With experience, the diver becomes more adept in their control and the variances in their buoyancy and trim are reduced.

This phase is about learning the mechanisms needed to control your depth and orientation in the water.

The next phase is of unconscious adjustment. With experience, the diver reduces the need to focus on the variable elements that keep them at a given depth, in a given orientation. Many control adjustments are made by the diver, but these become autonomous and instinctive.

This phase is about ingraining and forgetting the mechanisms needed to control your depth and orientation in the water.

The third phase is of conscious stillness. The diver learns to focus on being still, minimizing those control movements and allowing themselves to simply float still and relaxed at a precise depth and in the orientation of their choosing. With practice, the movement of legs, fins, arms etc are reduced further and further. The diver has to phase out macro adjustments, then phase out micro adjustments to become more and more stable whilst static in the water column.

This phase is about eliminating the mechanisms needed to control your depth and orientation in the water.

The final phase is that of unconscious stillness. The diver simply floats at the depth and orientation of their choosing, with little to no movement occurring in the limbs or need for bodily tension. Micro-adjustments are no longer necessary as the diver is inherently stable and relaxed. A slight fin movement, from the ankles...or toes.. is used for propulsion or changing direction, that is all.

This phase is about no longer needing to control your depth and orientation in the water.

I liken this to feeling like "just another particle floating in the ocean". The sensation is like lying on a coach at home, breathing as normal, not twitching a single muscle... it just happens and it's sublimely relaxing and undemanding.

Sublime stillness and stability is the ultimate goal to aim for. It can be achieved.... and it certainly is not impossible. For divers with only dozens, or even hundreds, of dives it may seem implausible or unattainable... but if you're willing to devote dedicated practice to the perfection of stable, still buoyancy for long enough, then it can occur.

I'm happy to prove it's not impossible if anyone's around my neck of the woods. :)
 
OP needs to practice oscillating slowly around a neutral point. Proper weighting to minimize the volume of air in the bladder helps reduce the divergent forces. Inertia and friction have a dampening effect and increase hysteresis, allowing modulation of breathing frequency, depth (amplitude), and offset (average lung volume) to achieve near-hovering state.

Pilots in training (and my teenager, getting his driver's license) often suffer from PIO. I think new divers do also. Pilot Induced Oscillation is a result of over-correction and can cause divergent swings around neutral, even in inherently stable systems. It simply takes the brain time to learn how to correctly modulate all available inputs to maintain stability (aka practice).

It reminds me of flying a tail-dragger, which is inherently unstable, with the main landing gear in front of the center of mass. Any unbalanced forces on the wheels (with ground) tend to rotate the airplane further in a direction that increases the divergent forces. To avoid ground-loops, new pilots are sometimes taught to 'pedal' or tap the rudders, waving the tail back and forth slightly on either side of center line, keeping the aircraft (on average) straight. Later, pilots with lots of practice no longer need this technique, and keep things straight without thought.

Of course, I'm simply restating what has been said above by others.
 
@DevonDiver the last one is extraordinarily difficult to achieve and requires a near perfect rig in terms of trim, particularly problematic with sidemount as you're aware, but is possible, just takes lots and lots of hours in the water. Great description though and very accurate to what I experienced through my progression
 
Thanks for the elucidating analogy. (Not being facetious)

Nice vocab!!! I had to google it. I will attempt to incorporate it into my personal lexicon.
 
Finally, all this is indeed taught at scuba classes.

This was not explained in the PADI OWD course at all. Apparently the first course is just to provide basic familiarization. and to help keep you from accidentally killing yourself or your buddy in an emergency situation?

It appears that if I want to actually know how to be a proficient diver, I need to sign up for an untold number of additional courses, for a fee of course, whereupon the mysteries shall be revealed.

I feel like I've signed up to join a secret society, PADItology. Whoops, can't tell you those nuanced details of the craft until you have a 6th degree in the mystic arts, and know the special 3rd initiate handshake. Also, please have your credit card ready...


Thank you to everyone replying here for breaking the paywall and discussing this openly.
 
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This was not explained in the PADI OWD course at all. Apparently the first course is just to provide basic familiarization. and to help keep you from accidentally killing yourself or your buddy in an emergency situation?.

What you've learned is simply that the quality, motivation and expertise of diving instructors varies significantly.

When sourcing scuba training, it pays dividends to research your options based on the instructor who'll teach you. There's plenty of threads here on Scubaboard that give on advice on what to look for.

Buoyancy and hover is a performance standard that requires student mastery on the Open Water course. What varies is how the individual instructor defines "mastery".... and consequently, how much time and effort they devote to developing that capability.

I'm guessing your OW course was "bare minimum" in dives and duration.... that's 4 open water dives.... which leaves little time for developing higher level competencies.

It's sad that so many instructors teach based on the 'bare minimums'.... but it keeps the costs down and allows them to quote for training on a fixed price.... which is what most noobie divers seem to want (rather than good training).

The drawback is that with a cheap, convenient 'bare minimum' course.... the instructor has to downgrade the idea of 'mastery' to what is achievable in that bare minimum trainng time. Hence... very weak competencies.

You get what you pay for... and the Open Water course isn't limited (or meant to be) only four dives. It's meant to take as long as necessary for students to 'master' the syllabus skills.

In general, however.... find an accomplished technical diving instructor for your courses.... as tech instructors typically have to work more diligently with their students on precision buoyancy and trim. Technical diving has (should have) very high standards of fundamental skills. That teaching expertise can equally be applied to recreational diving level students.

Another option... and I am sure people will suggest this... is to look into the GUE Fundamentals course. PADI don't have an equivalent course... although any decent PADI tech instructor should be able to run equivalent training as a clinic.

It appears that if I want to actually know how to be a proficient diver, I need to sign up for an untold number of additional courses, for a fee of course, whereupon the mysteries shall be revealed.

It's a modular training process, tailored to be cheap, convenient and quick... which is what the majority of consumers want.

You opted for 'McDonalds'..... understand why you didn't get a Fillet Mignon....

You could have paid a lot more for a much more comprehensive course.... with PADI or another agency. But you didn't....

For example... I charge $95USD per day tuition expenses on all my recreational level courses, including Open Water. I have very high standards.... and students don't progress through the course until they demonstrate skills to my definition of 'mastery'. It's performance related qualification.... you pay for training, but need to earn certification.

Unsurprisingly, it's actually very rare for a 'wonder student' to get through that training in the bare minimum of days/dives. It's usual that repetitive/remedial dives are necessary. The average is about 5-6 days training. Slow learners can take longer.

More tuition time - costs more (shock!).

But a performance related 'mastery' timescale is defined entirely by student competency and motivation to learn. My students learn to dive exceptionally well... and don't struggle with buoyancy/trim after qualification. No secrets withheld...

So... nobody can complain about the standard and comprehensiveness of the training given.... but it does demand substantially more student commitment in respect to time, money and hard work.
 
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I am coming more and more to the conclusion that buoyancy management for new divers like myself is being taught completely wrong, which is probably why it is so difficult for new divers to figure out.

If as a new diver you feel bad because you cannot remain perfectly still above the sea floor, don't worry about it, because it is physically impossible for any diver to do it without breath-holding. Hovering vertically motionless without moving up or down, is basically impossible without dying from it.

Examining the physics of it, hovering at a perfect height/depth is an inherently unstable condition.

Assume you have a weighted and pressurized balloon filled with air that is perfectly balanced at a given depth. (This does not describe a diver because divers must breathe and therefore constantly change their internal air volume.)

Let's move the balloon down slightly in the water. As it descends, water compresses the air, so the balloon shrinks slightly. This causes the balloon to become slightly less buoyant, so it begins to sink of its own accord. As it continues to sink, it is compressed further so its volume decreases further and it further loses buoyancy. So the result is by moving the balloon down slightly from the equilibrium point, it begins to sink and then sinks faster and faster, as its volume continues to decrease as it is compressed.

Okay, let's instead move the balloon from the equilibrium point, up slightly in the water. As it ascends, the compression decreases so the balloon expands. Its buoyancy also increases as it displaces more water, so it begins to rise on its own, and further expands, etc, until it too is rising faster and faster.

The goal of a diver is therefore achieving a balance between rising uncontrollably and sinking uncontrollably.

Perfect buoyancy balance is impossible because of the need to breathe air to survive. Even if you could get your BC's internal volume perfectly balanced, you are constantly screwing this up every time you inhale or exhale.

Therefore because perfect buoyancy equilibrium is impossible, it seems that the real goal is to try to cycle back and forth across that unstable point, to keep the forces balanced:

Assuming all else is in perfect balance and motionless:
- As you breathe in, you will begin to rise
- As you breathe out, you will begin to sink

This drifting up and down with each breath is very small, perhaps at first only a few centimeters of distance around the unstable equilibrium position at the start of each drift cycle.

Therefore:
- As you begin to rise, breathe out. As you begin to sink, breathe in. Try to detect your rising and sinking, and learn to balance your breathing so that it is in opposition to the slight rising and sinking.

- If you begin to rise too much, breathe out more to counteract. If you begin to sink too much, breathe in more to counteract. We have a fairly large lung volume available, so can still breathe in and out slightly with your lungs nearly empty or almost as full as possible, using it as an air bladder rather than your BC.

- If you rise or sink faster than you can control by managing static lung volume alone, now it is time to reach for the BC to adjust it.


Stable buoyancy position management apparently needs to be treated as a game
, of constantly adjusting and balancing the breathing cycles, to match the constant unstable drifting up and down.

Can this game be taught, rather than it being left to each new diver to fumble through and figure out for themselves over the course of many dives, and who have to try to do it without an understanding of how to actively achieve it?
Yes. After only three hours of remedial training -NOT the nonsense "thousands of hours of in-water" or even 5-6 days as Andy Davis [DevonDiver] claims above. . .

A Method by which to learn, develop & practice Precision Buoyancy:

Extreme Scuba Makeover · UTD Scuba Diving
 
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https://www.shearwater.com/products/teric/

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