Video from a Training Dive with John Chatterton

[johndiver999]

All I can say is, 60 feet was the number we were taught to aim for. In practice it seemed controlled to me, and it was certainly nice to get out of the decozone quickly. I can see why a faster ascent rate would be valuable for doing very deep dives, but I don't have enough experience to comment more.



One thing we were taught is the importance of not overfilling the SMB at depth, as it can be challenging to have the OPV releasing gas at 'random' as you ascend. The goal was to get it about 1/5 full at that depth, if I had overfilled it I would have emptied a bit before beginning my ascent. Beyond that, I didn't find it difficult to release gas as normal from my BC to control my ascent rate, and it was impressive how effective paying out the spool ten feet below the first stop and using that to come to a stop was.

Can you help me understand more what the failure mode of the strategy is? If I was really getting pulled up by the SMB at depth why couldn't I just let the line pay out (or worst case let go of the spool)?

Thanks for the responses. I read your response as confirmation that the initial ascent rate was 60’feet perminute for the full minute and this was intentional and an integral part of the training. I don’t have one of those high end computers, but I think mine would complain a little about it. If that’s what the curriculum includes, I’m not trained enough to question it further.

With respect to the smb, you asked what problems that technique might cause. First I think it is unnecessary. Why delay your ascent initiation and play with the smb, why not just start going up? Anything that unnecessarily delays initiation of ascent would seem to be something to avoid.

The next issue is the ascent. Why occupy one of your hands to control an expanding smb? If an emergency occurs, air share etc. having your hand unnecessarily occupied would be undesirable.

The next issue is that the air in the smb would be expanding, so every second of the ascent would make it harder to hold. If you drop it and it flies away then you would start sinking.

Also another negative is that you indicated you can just let go if something happens. If you intend to let go, but screw up and get entangled in it when it is close to full, now you have a potential for a run away ascent. If on the other hand you are releasing from the bottom or 40 feet, you don’t have to put much air in it, so if you release and get entangled, you have a much better chance of salvaging the situation because the smb is only marginally inflated.

I just don’t see the value of delaying the ascent, occupying a hand and complicating the ascent and buoyancy control for seemingly no benefit.

The negatives of this practice are pretty clear to me, and possibly they could be offset by some advantages, but I am struggling to come up with any benefits of that strategy

 

[njdiverjoe]

The negatives of this practice are pretty clear to me, and possibly they could be offset by some advantages, but I am struggling to come up with any benefits of that strategy

The wrecks down there can have some pretty wicked current. I'm a NE diver, but when I did my ccr trimix down there, there was an emphasis placed on getting a bag/smb to the surface before leaving the wreck so the boat could track you during deco.

We rode bags up to our first stop as well, because if you have to shoot it anyways...

 

[johndiver999]

The wrecks down there can have some pretty wicked current. I'm a NE diver, but when I did my ccr trimix down there, there was an emphasis placed on getting a bag/smb to the surface before leaving the wreck so the boat could track you during deco.

We rode bags up to our first stop as well, because if you have to shoot it anyways...

Exactly, you either launch from the bottom or put air in the bag at the first stop and release, but the procedure taught is neither of those.

 

[ChuckP]

I agree Ken, which is why in over 150 posts NOT ONE has criticized the students in this course and it has all gone towards the instructor/instruction in general. They are newer divers, they are enthusiastic, and they are eager to learn which is great. I think the issue that many are having is that the instructor in question was not even attempting to fix some of the buoyancy, trim, propulsion techniques. In fact the instructor with his thousands of dives looked JUST LIKE the students and was actively promoting bad form. We should be mindful that this was just adv. wreck and that some other instructor certified them on AN/DP. If this had been a trimix course, the instructor would have been teaching them the same techniques with the same (I would call them lax) standards and these students would be at the top of the OC certification pyramid with the skills demonstrated (or not demonstrated) in that video. There would have been no OC dive they were not certified to do.

The course might prepare them for some wreck diving navigation and techniques, but in terms of actually learning how to dive in a skillful, safe, and responsible manner they are actually getting a better education on this thread, website, and (some) youtube videos. It’s not that they dive like that and it’s not that they are in a class. It’s that they look like that, are in a class, AND it’s not being addressed by the instructor.



I thought the lift bag was an interesting idea. I don’t use open bottom lift bags, but it does seem like an interested idea. I actually really liked the spool recovery technique. If I drop a spool my thoughts were that I still have the line going up attached to the bag so I will just reel it up at the end of the dive or deploy a backup if needed. The pulley technique is interesting as a solo/self reliant technique.



Chuck you have a quote attributed to me in post #114 that I did not say. Can you please remove/edit it.

I touched upon the need to address buoyancy and basic skills in my previous post, but I will add a little more here.

Having good buoyancy skills is important for a couple of reasons. Having good buoyancy stops situations from requiring survival techniques in the first place. Good buoyancy also stops bad situations from becoming much worse.

How many fatalities have been caused from bad buoyancy? Going into the cave didn’t necessarily kill them, going into the wreck didn’t necessarily kill them. Silt and clay stirred up from bad buoyancy (and kicks) caused the situation to become fatal and there is a good chance that bad buoyancy stopped the situation from improving by stopping the clay/silt out from dissipating. He might be address some wreck specific survival skills, but I would argue that buoyancy is the first line of defense for survival in scuba.



I understand about CO2, but I believe he is using it as an excuse for some poor practices. Doctor Mike posted above that trim isn’t the goal diving. While limiting CO2, especially in big dives, is important; limiting CO2 is not the ultimate goal of diving. Proper form and good technique can limit CO2 build up just as much, maybe even more than some of the techniques that I have seen John employ. If CO2 retention is really the goal then he should be advocating trimix at very shallow depths.



Perfectly said. We play the way we practice. In an actual emergency, the skill level that we exhibit will always be at least a little bit worse than our average. Diving is mostly safe and it is supposed to be fun, but how we handle the rare emergency is the difference between life and death.

Fixed it - that came after trying to condense and get under the max words for a post

There are many instructors out there that teach differently and at the more advanced level, the methods of teaching can vary widely - just like the diving we all do.......

I forget who, but a tech instructor I believe recently talked about taking a deco class in a cave, he requires his students to complete one open water deco dive also - something to the effect that cave deco is easier than open water drift deco, something I never really thought about but it goes to the thought that diving can and is different - one system will never best case apply to all diving.

You the potential tech student that might be reading this - think for yourself as to how you plan to dive in the future, how is this new training going to help you see what you desire to see and see it safely. Search out an instructor that teaches in a way that will benefit you the most - the famous guy might not be it. Find an instructor that will focus on the things you feel are the most critical, I have to believe, the more comfortable you are, the more you'll learn.

 

[Heat Miser]

The negatives of this practice are pretty clear to me, and possibly they could be offset by some advantages, but I am struggling to come up with any benefits of that strategy

Advantages:
1. learning how to use a back-up buoyancy device
2. learning to inflate it in a neutrally buoyant manner. (so you knees aren't touching that delicately handcrafted oxidizing US steel
3. a line pointing an approximate direction to surface (current dependant)
4. a marker so that the boat captain/dive master know where you going to be on surface.
5. a marker so other recreational boats don't run over you, when you surface.

 

[ls23]

I don't think anyone is arguing against the practice of shooting an (one!) SMB to have a reference in open water and mark your position for the boat. The strange part is actually riding it up and hanging on to it for deco. It just seems like a crutch for a lack of ability in proper ascents and holding stops that just complicates things unnecessarily.

 

[Heat Miser]

The strange part is actually riding it up and hanging on to it for deco. It just seems like a crutch for a lack of ability in proper ascents and holding stops that just complicates things unnecessarily.

I know I'm going to try it and make up my own mind.

 

[kensuf]

The wrecks down there can have some pretty wicked current. I'm a NE diver, but when I did my ccr trimix down there, there was an emphasis placed on getting a bag/smb to the surface before leaving the wreck so the boat could track you during deco.

We rode bags up to our first stop as well, because if you have to shoot it anyways...

THIS!

In July I got to deco in a 4kt current. People were still talking about "that day on the Hydro" when I was there this past weekend.

 

[kensuf]

There are many instructors out there that teach differently and at the more advanced level, the methods of teaching can vary widely - just like the diving we all do.......

I forget who, but a tech instructor I believe recently talked about taking a deco class in a cave, he requires his students to complete one open water deco dive also - something to the effect that cave deco is easier than open water drift deco, something I never really thought about but it goes to the thought that diving can and is different - one system will never best case apply to all diving.

You the potential tech student that might be reading this - think for yourself as to how you plan to dive in the future, how is this new training going to help you see what you desire to see and see it safely. Search out an instructor that teaches in a way that will benefit you the most - the famous guy might not be it. Find an instructor that will focus on the things you feel are the most critical, I have to believe, the more comfortable you are, the more you'll learn.

That was me.

I had a normoxic class down in Pompano this weekend doing their final two dives off a boat. They're both cave divers, it pushed them outside of their comfort zones but after the weekend was over they both agreed the experience made them better.

 

[Zack-Bloom]

FYI Now that the furor has died down I took the video down for a bit to fix a couple things. It will be back soon.