Reasons to take a propulsion/trim/buoyancy class...

[boulderjohn]

Give me two pool sessions if you're a non-diver or one if you're a diver. You won't be perfect, but you'll have the tools to get mostly there in another 10-20 dives.

The most recent student I had in my new TecReational Diver specialty class, which focuses on trim and propulsion, had only gotten his OW certification the month before and had only done one dive trip with no additional training. After our first pool session, the OW instructor who was sharing the pool with us said that my "cave diving student" really looked good. He was shocked to learn that this was a beginner. By the end of the second pool session the only kick he wasn't doing really well was the back kick. We nailed that on the third pool session. I haven't seen him since then, but from what he tells me about his practicing, I think he would probably walk into a cave class now and not be chased away. He has not started his AOW yet. Students can learn this remarkably quickly if you make it the focus.

 

[mselenaous]

I will be the first one to say that my time with NetDoc has made me a much better diver. Not only do I finally have good trim but I have learned the art of being able to control my buoyancy with my breathing instead of constantly using my inflator and then dumping air. I am also much more aware of my position in the water and what impact I am making (or trying not to make) on the reef.

Before this class, I was using my inflator regularly, was almost vertical, and was constantly silting up the bottom. Now I can control my position with my breathing, am pretty horizontal, and barely stir up the silt. Well worth your time to take a trim/propulsion/buoyancy class no matter who you were certified with.

Can't wait to see you in the water

 

[The Chairman]

You know John, I haven't spent a lot of time introducing the back kick to my students unless they ask for it. Perhaps I should rethink that.

 

[supergaijin]

Buoyancy control and trim can come through 'self awareness' but this requires more time than the average diver gets to spend in the water over their lifetime.

/snip/

Some students learn and respond during a session but quickly revert to 'old habits' without reinforcement from another diver.

Give me two pool sessions if you're a non-diver or one if you're a diver. You won't be perfect, but you'll have the tools to get mostly there in another 10-20 dives.

I'm not doubting you Netdoc. My point is that it is possible to have excellent trim etc. through spending thousands of hours underwater, but this is not realistic, thus a dedicated course is the way to go.

After the said course, divers can and do revert to bad habits without reinforcement. The 10-20 dives after the training is the 'make or break' period. If the diver is surrounded by poor divers for this period, it is easy to slip back. It is up to the individual to use the skills/techniques attained during the course- the instructor has no control over that IMO.

 

[aeweems12]

Can't wait to see you in the water

Can't wait to come back down and dive with you and Pete again! Maybe Pete can introduce the back kick to me

 

[Pook-60]

Howdy

Recommend this is thread is posted as a "Sticky". Fantastic topic and very relevant responses.

TX
Dane

 

[boulderjohn]

You know John, I haven't spent a lot of time introducing the back kick to my students unless they ask for it. Perhaps I should rethink that.

It does take a while--the motion is unnatural. There is a secondary value to teaching it--much of the motion is essentially the same as the helicopter turn, so you are killing two birds with one stone.

 

[beanojones]

In one picture that was taken of me I was practically vertical, and I didn't like that at all.

Worth pointing out that vertical is perfectly fine and very useful. (As long as the head is at the bottom, not the top)

In fact, for people wanting to work out their buoyancy, doing headstands with the face an inch or two from whatever bottom you got will be a very effective way to recognize buoyancy issues. Once buoyancy is worked out, th trim and propulsion have a way of sorting themselves out naturally because a neutrally buoyant diver who is out of trim will send themselves up, hand usage will send them up.

And a neutrally buoyant dive will also probably get sick of the left/right bounce of the flutter, and learn to use each fins to do all sorts of things.

---------- Post added August 1st, 2013 at 10:27 PM ----------

Buoyancy/trim/propulsion is definitely part of my AOW course curriculum. I once had an AOW student ask me which dive was our buoyancy control dive. I said "all of them" ...

Exactly!

At one point does it make sense for a diver to not be neutral? So since we are training divers, at what point would we ever want them to not be neutral, since we are, after all, training divers, not gear manipulation machines?

I never use the word hover in my OW class, either, because at what point is hovering not simply expected behavior if not actually moving forward or swimming up? (Similarly I simply do not label many "SKILLS" because frankly they are just expected continuous behavior, or expected responses to things that can just happen during a dive. I have students ask me all the time "when we are going to do the skills?", after doing dives of doing continuous skills of neutral buoyancy, in trim swimming, proper buddy procedures, interspersed with mask removal, reg recovery, etc.

As many have pointed out again and again, the student materials extremely useful for students to get a handle on things to come have become the unfortunate default location where many instructors have come to look for guidance on how to do skills. Call one overweighted diver forward, do fin pivot, dump air from BCD, go back to the line wash rinse repeat. Then the overweighted divers all start off beating the hell out of the sand.

---------- Post added August 1st, 2013 at 10:34 PM ----------

One of the biggest takeaways from my PPB class is the ability to compensate when I'm over or under weighted. Here is what my instructor did at the beginning of the course. We started off with simple hovering: vertical, horizontal, upside down. Then he handed me a 2lb weight and we did it again. Then another 2lbs. At first it feels impossible, but after a few minutes you realize you really can compensate with lung volume. Then he had me inflate my BCD until I was comfortably neutral with the extra 4 lbs. Then (you guessed it) he took away 2lbs at a time. When we were done, I could get neutral within an +/-4lb window... 8lbs! And I used to fret over a pound or two! I had been trying to improve my buoyancy on every dive, but I don't think that on my own I would have ever been able to make the breakthroughs that my instructor facilitated.

And this is a great idea for training divers who because they mostly dive when travelling, have little input on what sort of gear they get handed to go diving with, and can easily end up with tanks, wetsuits and BCD with all kinds of ballast. One of the shops I used to work with actually used a first dive and second dive tank which varied by 6 pounds of buoyancy which meant that even divers who though they had it dialed in on the first dive would suddenly be 6 pounds more negative on the second!

The actual technique of holding a two pound weight in your hand is something I have seen clever travel divers do to compensate for the fact that jackets tend to give less than optimal trim when diver are wearing too much on their belt.

---------- Post added August 1st, 2013 at 10:44 PM ----------

You know John, I haven't spent a lot of time introducing the back kick to my students unless they ask for it. Perhaps I should rethink that.

For me, the reason to talk back kick, and helicopter is to give students something to try instead of hand usage.

For most OW students, they will end up in a bunch of heads staring at something at some point and wonder how to get away from the crowd without handwaving and potentially ripping the surrounding divers regs and masks out. Deep inhale if on top, but....

If you have introduced OW students to the idea that a neutral diver committed to not using their hands will learn all sorts of ways to use their fins, you can at least get some people giving helicopters and back kicks a shot.

 

[The Chairman]

Once buoyancy is worked out, th trim and propulsion have a way of sorting themselves out naturally because a neutrally buoyant diver who is out of trim will send themselves up, hand usage will send them up.

I find quite the opposite to be true. Until horizontal trim is established, getting neutral is nigh to impossible except for a minute at a time. Most divers in the head up slant position have to be over-weighted while moving to compensate for their upward thrust from kicking. When they stop, they have to scull to maintain that upward thrust. It's a vicious cycle that is engendered by well meaning instructors who think they have helped their student achieve neutral buoyancy by showing them how to do a sixty second hover. Getting divers perfectly horizontal is the key to teaching great neutral buoyancy. Getting it bassackwards will only cause confusion and prolong the learning curve. FWIW, my student's aren't required to hover for sixty seconds. They are required to do their entire dives mid water in a horizontally trimmed position.

For me, the reason to talk back kick, and helicopter is to give students something to try instead of hand usage.

The use of hands to change direction is not permitted in any of my classes. One of the first signs taught is the sign to put their hands together. All turns must be accomplished via fins and the helicopter is taught if they can't figure it out on the first or second turn. I say that, but I've never had to teach it. Once my students get their trim straight and learn the frog kick, the helicopter turn just comes naturally. I do accept a one fin only turn. It's actually a NASE OW standard for a student to be able to stop and turn without using their hands.

 

[beanojones]

I find quite the opposite to be true. Until horizontal trim is established, getting neutral is nigh to impossible except for a minute at a time. Most divers in the head up slant position have to be over-weighted while moving to compensate for their upward thrust from kicking. When they stop, they have to scull to maintain that upward thrust. It's a vicious cycle that is engendered by well meaning instructors who think they have helped their student achieve neutral buoyancy by showing them how to do a sixty second hover. Getting divers perfectly horizontal is the key to teaching great neutral buoyancy. Getting it bassackwards will only cause confusion and prolong the learning curve.

It's a little more complex than that.

The three components: breath control, trim, and amount of weight/air in the BCD all pretty much have to be in place for any one of the three to work in motion. But neutral buoyancy can be worked on while the trim is still in process.

Getting them horizontal is great positively buoyant on the surface, but it has the prerequisite of already being neutral once under water, otherwise they are doing pushups to stay off the bottom too often.