SDI DMs and up must demonstrate skills while neutrally buoyant

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I routinely do all the basic 5 or 6ish skills while neutral and in trim but have a hard time imagining a scenario where I would have to remove and replace my bc at depth, little lone while neutrally buoyant.

The only scenario I could imagine would be diving solo and having to deal with a major failure in 1st stage or dealing with a major problem entanglement. Even then, in most cases seems like it would be better to be execute ascent without wasting time.

Perhaps I just don’t have a good enough imagination.
Its more a skill of body control and bouyancy, while taskloaded.
Similar to the attachment of the spool to the dsmb. In a real world its most likely already atached. But its a good bouyancy skill.
 
How do you separate trim from buoyancy and proper weighting?

How can you think that they are NOT separate?

Your proper weighting has no dependence on your buoyancy skills or what orientation your body is in.

Your buoyancy can be neutral, no matter what weighting you have (as long as it's at least enough). And it certainly does not depend on what orientation your body is in.

Your trim (the orientation of your body in the water) can be perfectly flat/horizontal/sky diver position, even if you are totally over weighted and even if you are going up and down like a yoyo.
 
How can you think that they are NOT separate?

Your proper weighting has no dependence on your buoyancy skills or what orientation your body is in.

Your buoyancy can be neutral, no matter what weighting you have (as long as it's at least enough). And it certainly does not depend on what orientation your body is in.

Your trim (the orientation of your body in the water) can be perfectly flat/horizontal/sky diver position, even if you are totally over weighted and even if you are going up and down like a yoyo.
I should have consulted you before SDI published my three part series on how I teach neutrally buoyant and trimmed. Darn. </Sarcasm>
 
Nobody's mentioned proper finning skills -- the third of the three core skills for perpetual happiness as a diver...
 
Nobody's mentioned proper finning skills -- the third of the three core skills for perpetual happiness as a diver...
Good point to spell it out specificially. In my mind, it is automatically part of it.

But when one makes assumptions.....
 
Good point to spell it out specificially. In my mind, it is automatically part of it.

But when one makes assumptions.....
And we all know that makes an ass-u-me.

:)
 
How can you think that they are NOT separate?

Your proper weighting has no dependence on your buoyancy skills or what orientation your body is in.

Your buoyancy can be neutral, no matter what weighting you have (as long as it's at least enough). And it certainly does not depend on what orientation your body is in.

Your trim (the orientation of your body in the water) can be perfectly flat/horizontal/sky diver position, even if you are totally over weighted and even if you are going up and down like a yoyo.
So how do you teach your new OW students the relationship between weighting, buoyancy, and trim? How do you teach proper weighting if you don't teach buoyancy control and proper trim? And how do you teach buoyancy control without proper weighting so that students are not struggling to not yoyo and get horizontal? What is your method for getting them neutral and in trim by the end of the first or second session on scuba? I describe mine in my first book.

For new OW divers proper weighting is critical to teach them good buoyancy control and trim so they are not fighting to achieve it.

For experienced divers one can possibly get in trim while being overweighted but it takes some work. Posture, body composition, type of BC, buoyancy characteristics of other gear carried, etc., can make it a real challenge. I have always taught that buoyancy and trim are tightly connected.
Starting with not only the proper amount of lead but the placement of it depending on the person. Trim is not easy for some people to achieve without putting the lead where it needs to be when they first start learning.

Some people with more body fat need the lead to be lower or higher on the body when in a horizontal position to be able to get into good trim without fighting for it.
Getting in trim also very much depends on the the way any air is distributed in the BC and if using a drysuit the issues are compounded.

Yes you can be neutral while overweighted but that necessitates a larger volume of air that is going to shift when you get horizontal. Being properly weighted gives the diver a better chance of managing any issues if less air is required to remain neutral so neutral buoyancy and trim are directly connected.
Someone going up and down like a yoyo is more than likely not going to be in trim.

They are either finning to get down with their head down or trying to fin up because they are having problems controlling their buoyancy. Going up and down like a yoyo is indicative of someone who has not grasped the idea of proper weighting and how it affects control and position.
Saying that weighting, buoyancy, and trim are not connected is simply not true.
 
So how do you teach your new OW students the relationship between weighting, buoyancy, and trim? How do you teach proper weighting if you don't teach buoyancy control and proper trim? And how do you teach buoyancy control without proper weighting so that students are not struggling to not yoyo and get horizontal? What is your method for getting them neutral and in trim by the end of the first or second session on scuba? I describe mine in my first book.

For new OW divers proper weighting is critical to teach them good buoyancy control and trim so they are not fighting to achieve it.

For experienced divers one can possibly get in trim while being overweighted but it takes some work. Posture, body composition, type of BC, buoyancy characteristics of other gear carried, etc., can make it a real challenge. I have always taught that buoyancy and trim are tightly connected.
Starting with not only the proper amount of lead but the placement of it depending on the person. Trim is not easy for some people to achieve without putting the lead where it needs to be when they first start learning.

Some people with more body fat need the lead to be lower or higher on the body when in a horizontal position to be able to get into good trim without fighting for it.
Getting in trim also very much depends on the the way any air is distributed in the BC and if using a drysuit the issues are compounded.

Yes you can be neutral while overweighted but that necessitates a larger volume of air that is going to shift when you get horizontal. Being properly weighted gives the diver a better chance of managing any issues if less air is required to remain neutral so neutral buoyancy and trim are directly connected.
Someone going up and down like a yoyo is more than likely not going to be in trim.

They are either finning to get down with their head down or trying to fin up because they are having problems controlling their buoyancy. Going up and down like a yoyo is indicative of someone who has not grasped the idea of proper weighting and how it affects control and position.
Saying that weighting, buoyancy, and trim are not connected is simply not true.

Thanks for the exposition on the basics of scuba.

It seems like you are asking me to write out our whole OW class here. Ain't nobody got time for that.

How do I teach proper weighting to new students? Well, it's not that hard to understand that you need the least weight possible and still be able to hold a safety stop with a near-empty tank. Our students seem to be able to grasp that pretty easily. And it has nothing to do with how good their buoyancy is or what their trim is. Their proper weight is their proper weight, whether they are in horizontal trim or not, and whether their buoyancy control is not-great or great.

How to teach buoyancy without proper weighting? Who said I do that? They are being taught about weighting, buoyancy, and trim all at the same time. As it happens, they usually start with X amount of lead and by the end of their last checkout dive, their breathing has improved and they have shed some amount of lead compared to their pool session. So, in addition to the explanation of how proper weighting affects one's ability to control one's buoyancy, they also get to experience how carrying less lead makes buoyancy control easier. Notice that I didn't say weighting and buoyancy have no effect on each other. I just said they are separate.

You can control your buoyancy without being properly weighted (as long as it's ENOUGH weight). I have seen many new (to newish) divers that use "I had a couple of pounds too much weight" as an excuse for not demonstrating good buoyancy control. They probably had some instructor who taught them that buoyancy and weighting are somehow inextricably tied together and you can't have one without the other. False.

Similarly, it's not hard to explain to students how distribution of the weight they are carrying affects their ability to maintain flat trim in the water. I mean, I don't know about you, but my students seems to understand it after a fairly short verbal explanation. Whether they have good buoyancy control or not has nothing to do with whether they are diving in trim. Whether they have the right amount of weight or over weighted also does not. Having whatever weight they are carrying distributed correctly is the key to making horizontal trim easy and natural.

In the end, I guess it is results that really matter. Since I moved to SC and joined my current shop, I have been seriously amazed. I take no credit for it, but we consistently turn out students that are diving in horizontal trim and with decent buoyancy control after one 2 hour (-ish) pool session. Our "norm" is one pool session (taught by instructors who are neutrally buoyant and in horizontal trim) and then go to OW for checkout dives. I think all credit goes to John and Amanda Baker. I rolled in here 6 months ago and joined the program they were already teaching. At first, I asked "how can you possibly turn out OW students that are ready for OW checkouts after just 1 (relatively short) pool session?!?" Now that I've been part of those pool sessions, I see that what they (we) are doing does work. Of course we do occasionally have students that need more time in the pool - and they get it. But, MOST of our students are ready to go to OW checkouts (with decent buoyancy and decent trim) after 1 pool session.
 
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