I f*** up and I am ashamed

[Capt Jim Wyatt]

Many instructors say dogmatic things

That is for sure....

 

[Dan]

I was using my Zeagle Ranger BCD, a model which then had two waist pockets only.

That's my old BCD that I had trouble venting off trapped air pocket. I'm now very happy with my Cressi TraveLight BCD. No more doing gymnastics just to get rid of the last trapped air at the shallow.

 

[markmud]

You are too kind, but your point is true: you can't expect an instructor with little or no clue or care about trim and buoyancy to impart such. I've taken a number of classes, where it seemed my skillset was superior to my instructor. That's not to toot my own horn (toot, toot), but was an indication that I needed a better instructor. There are a few peeps I owe my trim & buoyancy to: Reggie Ross, Jim Wyatt, Tom McCarthy and Mike Brady are the standouts. Of those three, I believe only @Capt Jim Wyatt and Tom McCarthy are still teaching. Yeah, I also owe it to ScubaBoard in general. Like dody, I tossed out ideas only to have them handed back to me in tatters. Sometimes I was partly right, mostly I still had a lot to learn. I still do.

Pete,

I was not being kind. I was really impressed. You were like a mini and more maneuverable version of a Los Angeles Class Submarine (no personal puns intended). If you became an u/w hunter/killer, you would be deadly! Your movements were precise and your fin kicks were very subtle. I am not trying to blow smoke up your sphincter.

I am getting to a point. A point that Dody may want to think about.

My diving became really fun after my instructor and I dove together (instructor Rick). I was not a failed diver by any means at that point (100+ dives). By seeing Instructor Rick dive in perfect form, trim, and completely, and absolutely, neutral, I was challenged to emulate his diving acumen. Will I ever dive like Instructor Rick? HELL NO!

However:

• I am having more fun diving in good trim, like Instructor Rick.
• I am having more fun diving in my "sweet spot" in terms of sinker load and sinker location in my kit.
• I am having more fun diving in good trim and proper weighting because I use less gas.
• I am having more fun using my tidal volume to fine tune my buoyancy, rather than using my BC bladder.
• I am having more fun diving by exercising, including biking and running, in order to have healthy lungs with decent tidal volume and a high tolerance for getting winded (example: swimming against currents or towing my wife into a current).

Your trim and buoyancy orthodoxy is beyond religion. It is how a diver learns to have real fun under water.

Being in control of my buoyancy from 0 to 100 fsw without having to use my BC bladder is really fun, whether I am starting the dive or ending it.

I am going to paraphrase something you keep harping on in your sermons: Mastering buoyancy and trim equals fun diving! Buoyancy and trim are big issues for you, and it is not religious--it really is the key to fun diving.

cheers,
m

 

[Dody]

I am super impressed that you have come to a public forum with your story. We all learn when people do this, so thank you.

You have been given quite a bit of good advice about diving and what to do differently next time. I cannot add to any of that, yet I can add to some of the ideas shared about diving with a spouse. My wife and I have about 200+ dives together and we will debrief after many dives about one thing or another. A frequent topic early in our diving together was communication and expectations. We often invented our own underwater signals for specific things based on the previous dive during these debriefs.

These debriefs would also lead to some great conversations about expectations in certain situations, one of which is always signaling if each of us is OK prior to a swim through as well as establishing some signals regarding who will be first to enter. This sounds similar to what Kimela posted earlier. A great outcome of these debriefs and discussions are that they were great for our relationship (The Chairman mentioned this, too). We bonded over these debriefs and invented signals. They also helped establish the fact that we are a buddy team, rather than two divers with one of us "being in charge."

Well. Isn't the purpose of a forum to share experiences? There are many well educated divers on SB. They might not realize that but they acutually educate me... when they stay civil.

 

[hedonist222]

the best part of dody's threads is that we learn a great deal from every one

 

[The Chairman]

I am going to paraphrase something you keep harping on in your sermons: Mastering buoyancy and trim equals fun diving! Buoyancy and trim are big issues for you, and it is not religious--it really is the key to fun diving.

Amen, brother. Amen!

Will the Dive Deacons please pass the plate now?

To add to Mark's point: the best instructors set the best example ALL THE TIME. It's why I won't teach on my knees, ever. It's why I oppose vertical CESAs being practiced. Every dive should consist of one descent and one ascent with a proper safety stop. Yes, even training dives. I'm not the best instructor out there, but I strive to be. Whether someone is looking at me or not, I try to lead by example.

For the record, Mark is an awesome diver in his own right. I would have no problems splashing with him just about anywhere. There are maybe a dozen divers I would say that about. Maybe two.

 

[Dody]

Let's look at your initial description of the event.


In that description, you said that early in the dive, while you still had plenty of air, you realized you were moving up, and you eventually reached the overhead at only 2 m of depth, which is very shallow. What would cause you to move up? You were becoming more buoyant, which happens due to expansion of gas at lesser ambient pressure (Boyle's Law). The closer you are to the surface, the more this happens. So what was expanding? It could be a wetsuit, but more likely it was the air in your BCD. This is extremely common with newer divers. The air in your BCD expands rapidly when you get near the surface, bringing you suddenly upward.

This does not suggest that you were underweighted. If you have enough air in the BCD for that to happen, you had more than enough weight, at least for that point in the dive (before air weight loss). Further, your struggles to get down strongly suggest the presence of expanded air trying to get you to the surface and being stopped from doing that by the overhead. When that happens, it can indeed be very difficult to descend, because you cannot easily get that bubble of air to the exit point. You can pull on dump valves all you want, but if that air is at a point higher than the dump valve, it isn't going anywhere.

So my diagnosis of the situation is that you had enough weight for the dive (at least at that point), and when you entered the overhead, you ascended somewhat. As you did, the air in the BCD expanded due to Boyle's Law and took you to the ceiling. Once there, you were unable to release air due to the fact that you were pinned to the ceiling and could not get the BCD air to an exit point.

If it ever happens to me again, I will better assess the situation. But honestly, I was scared.

 

[CT-Rich]

This discussion reminds me of Bloom’s Taxonomy. Being able to repeat that one should take responsibility for one’s own safety on a dive is very different from being able to understand and apply the information in a real world situation. The same can be said about proper weighting. I see plenty of divers on SB that talk about perfect trim as if it a canonical principle etched in granite somewhere.

It’s not. The same is true for buddy diving. There are very rational reasons to do it, but a newly minted diver probably has a very limited understanding of the underlying rational beyond “my buddy is my redundant air supply”. It may be a long time before a diver realizes a buddy is also a sounding board for new ideas, a second pair of eyes, a co-innovator, a set of breaks for you bad judgement and witness to your tall tales.

Cody got a lesson in proper weighting and how a buddy team should or shouldn’t work. How he progresses as a diver depends on how he applies what happened, not what he gets beaten up for in an online forum. If it becomes other divers clobbering him over the head with how crappy his understanding is or how f-d up his training was, the thing he will learn is not to post on the Internet.

 

[Dody]

Let's look at your initial description of the event.


In that description, you said that early in the dive, while you still had plenty of air, you realized you were moving up, and you eventually reached the overhead at only 2 m of depth, which is very shallow. What would cause you to move up? You were becoming more buoyant, which happens due to expansion of gas at lesser ambient pressure (Boyle's Law). The closer you are to the surface, the more this happens. So what was expanding? It could be a wetsuit, but more likely it was the air in your BCD. This is extremely common with newer divers. The air in your BCD expands rapidly when you get near the surface, bringing you suddenly upward.

This does not suggest that you were underweighted. If you have enough air in the BCD for that to happen, you had more than enough weight, at least for that point in the dive (before air weight loss). Further, your struggles to get down strongly suggest the presence of expanded air trying to get you to the surface and being stopped from doing that by the overhead. When that happens, it can indeed be very difficult to descend, because you cannot easily get that bubble of air to the exit point. You can pull on dump valves all you want, but if that air is at a point higher than the dump valve, it isn't going anywhere.

So my diagnosis of the situation is that you had enough weight for the dive (at least at that point), and when you entered the overhead, you ascended somewhat. As you did, the air in the BCD expanded due to Boyle's Law and took you to the ceiling. Once there, you were unable to release air due to the fact that you were pinned to the ceiling and could not get the BCD air to an exit point.

Ok. That leads me to the next question. How can we make sure that we purge all the air out of the BCD?

 

[rongoodman]

Ok. That leads me to the next question. How can we make sure that we purge all the air out of the BCD?

Go a little head down and use the bottom dump.