Shooting a bag (DSMB) in strong current conditions

[Compressor]

Thank goodness there is more than one way of doing things.
i can sharpen a pencil while holding the pencil in the right hand or left hand.

 

[taimen]

But there is only one way of Doing It Right

 

[CWK]

I think it was pointed out earlier in the thread that the plastic lining in the DSMB sometimes sticks to itself, which causes it to fail to inflate. The unrolling process could "exercise" the DSMB and remove the "kinks"? As a recreational diver, the DM/instructor is usually the one deploying the DSMB. I've yet to deploy a DSMB myself and I would probably unroll my DSMB first before inflating, just to make sure it will expand to full length as expected. I think the tendency is to always bring along a DSMB but not check it before every dive, like you would with other equipment.

Checking equipment before each trip is good practice. You can always unroll you DSMB to check it before each trip if you have any concerns. You should not have to check it before each dive. See additional comments below.

Please check out the following video. I think it is the official SSI DSMB deployment video, but don't quote me on that. There is one neat trick shown in it. The DSMB is rolled up with just a little air inside it. Not enough to affect a diver's bouyancy but sufficient to make the DSMB slightly bouyant. When the DSMB is released from the bungee it automatically straightens!


As I said at the beginning of this thread, my DSMB deployment is self taught because DSMBs did not exist when I did my OW and AOWD training 30 years ago. I did not mention that I had to demonstrate proficiency in DSMB deployment in some of the courses that I took over the last 12 months. In my drift dive speciality I had to demonstrate DSMB deployment to my instructor who is a Master Instructor. In my Self Reliant Diver course, I had to demonstrate DSMB deployment to my instructor who is a Course Director. In my SSI tech courses, I had 2 instructors. The first instructor taught me theory and confined water. The second instructor led the open water dives in the presence of the first instructor. I believe the first instructor was a tech instructor trainer. None of the instructors that I had to demonstrate DSMB deployment to had any issues with the way that I deployed my DSMB.

Since the diver in the OP's initial video is practicing, I thought the depth checks were done because she might be deploying in the "blue" at some point, where there are no visual reference points. The depth checks are taught as part of the process so it becomes muscle memory, covering more general DSMB deployment scenarios.

Depth checks are taught. But over and above reliance on the depth shown on your computer, one should also keep track of depth by reference to the environment that you are in. In the very specific environment of the diver in the OP's video, reference to the environment is more important than reference to the depth shown on the computer. It's like learning to navigate by compass (checking depth on computer), and natural navigation by reference to the environment (tracking depth by reference to the environment). Natural navigation and tracking depth by being aware of your position in relation to your environment are skills that are difficult to teach but you can develop these skills.

 

[lowflyer]

BTW, in academic discourse (irrespective of whether it is between two professors or between a professor and an undergraduate), no professor would ever say that his credentials are better in order to further his position in the debate. This is the quickest way to being ridiculed within the academic community.

It sure is important to me to know the credentials of people I'm going to take advice from, especially when dealing with activities that have some inherent danger.

 

[CWK]

It sure is important to me to know the credentials of people I'm going to take advice from, especially when dealing with activities that have some inherent danger.

It ts, but there is a way of asking for that nicely. A mine is bigger and better approach may work in the playground but it has no place in the world of learning and ideas.

 

[lowflyer]

It ts, but there is a way of asking for that nicely. A mine is bigger and better approach may work in the playground but it has no place in the world of learning and ideas.

This isn't academia here. This is a forum wherein most people don't know most other people. You posted your experience, and others posted their qualifications regarding the topic of the thread. That comparison is useful information to many of us to decide whom to give credence to.

 

[CWK]

This isn't academia here. This is a forum wherein most people don't know most other people. You posted your experience, and others posted their qualifications regarding the topic of the thread. That comparison is useful information to many of us to decide whom to give credence to.

In discussions of ideas , it is rhe idea that matters more, not your credentials. This may not be academia but we are discussing learning. The same principals apply.

 

[Trailboss123]

In discussions of ideas , it is rhe idea that matters more, not your credentials. This may not be academia but we are discussing learning. The same principals apply.

Hmm... Ideas, credentials, academia, learning, experience?--
I have been following this thread with interest. I have posted on and actually started threads here on Scubaboard regarding DSMB deployment. I am pretty passionate about it.

However, we have somehow now moved this thread discussion away from the actual skill of DSMB deployment and shifted it toward something other entirely (ideas, credentials, academia, learning, experience).

Since I have a Phd and lots of academia experience and I am also a certified diver with a certain level of real world experience; I thought I would share and post the following and I hope it might add some perspective:

Below is a photo of my son. He is an elite special forces operative (can't say with who or what)- I am only posting to lend some visual perspective and here is my takeaway:

There are some things in life that are fun to debate academically, regardless of credential. There are some things in life that you might even have a "credential" for that somehow outranks others in the same field, but you have very little real world experience in (me included).

And, there are other things with life and death consequences that some people have actually done repetitively and have a perspective on, and as a result, they have established some safe or best practices for. When it comes to life and death activities/consequences; I am going to rely on and pay attention to the people that have been there and done that repetitively and are still living to tell me about it.

 

[woodcarver]

It would have been nice to have seen these videos a few years ago. Use of an SMB was barely talked about in any of my classes-OW, AOW, or any of the specialties until I took Drift in Cozumel. Only reason for taking that cert was to have an instructor in the water to make sure my gf didn't drown while I was still figuring out this dive thing in current. Pedro was great, worth every penny.
First use was from depth, ~60', in current. Managed to send it up without it hanging up on anything or have it drag me up with it, but that 1st go would not have made a good training video...By the end of the week it was fairly simple. Did drop the reel once; that gave me something to do on the SS, rolling up 100' of line.
From reading a bunch of threads on SB, it appears to be sort of uncommon for a lot of divers to use their own SMB when diving places like Cozumel with a DM. I sent one up on all but a few dives, and on one that I didn't because we were close to the DM, had to defend myself from the swim platform of the boat. After that, I sent mine up even if we were going up with the DM.
Even though she didn't know how to use it, I hung an SMB and reel on her for her to get used to. About halfway through our 2nd trip she asked why she had to carry it since we always used mine. Told her it was "just in case". On the afternoon dive that day, inflated the SMB and the plastic snap popped of the reel and up it went, sans line. Reached over and unhooked hers and sent it up. She hasn't questioned the need for a 2nd since.
edit-Got the 1st back. The boat saw it pop up and they grabbed it.
Trailboss was posting while I was typing. Absolutely agree with him...

 

[divinh]

Checking equipment before each trip is good practice. You can always unroll you DSMB to check it before each trip if you have any concerns. You should not have to check it before each dive. See additional comments below.

Please check out the following video. I think it is the official SSI DSMB deployment video, but don't quote me on that. There is one neat trick shown in it. The DSMB is rolled up with just a little air inside it. Not enough to affect a diver's bouyancy but sufficient to make the DSMB slightly bouyant. When the DSMB is released from the bungee it automatically straightens!


As I said at the beginning of this thread, my DSMB deployment is self taught because DSMBs did not exist when I did my OW and AOWD training 30 years ago. I did not mention that I had to demonstrate proficiency in DSMB deployment in some of the courses that I took over the last 12 months. In my drift dive speciality I had to demonstrate DSMB deployment to my instructor who is a Master Instructor. In my Self Reliant Diver course, I had to demonstrate DSMB deployment to my instructor who is a Course Director. In my SSI tech courses, I had 2 instructors. The first instructor taught me theory and confined water. The second instructor led the open water dives in the presence of the first instructor. I believe the first instructor was a tech instructor trainer. None of the instructors that I had to demonstrate DSMB deployment to had any issues with the way that I deployed my DSMB.

I notice that in the video, the DSMB and reel are kept separate and assembled before deploying. Is that artificial task loading? Or does SSI have a rationale to keep them separate? Also, both DSMB and reel are kept in a pouch, probably to avoid possible unexpected unrolling and entanglements? Or is it more task loading? Finally, the thumb is inserted into the middle of the reel during deployment. That seems like a hazard, a way to lose a thumb or possibly get cuts if the DSMB were to ascend rapidly.

Depth checks are taught. But over and above reliance on the depth shown on your computer, one should also keep track of depth by reference to the environment that you are in. In the very specific environment of the diver in the OP's video, reference to the environment is more important than reference to the depth shown on the computer. It's like learning to navigate by compass (checking depth on computer), and natural navigation by reference to the environment (tracking depth by reference to the environment). Natural navigation and tracking depth by being aware of your position in relation to your environment are skills that are difficult to teach but you can develop these skills.

I'm not sure what you're arguing here. Are you saying that computers can't be relied upon for depth checks? What about when you're out in the blue, without reference points? If you have reference points, by all means, use them, but if not, then what?

When you're taught to drive, you're told to check the mirrors often, but once you're comfortable with driving, you know that you don't need to check as often because you've gained better situational awareness of what is around you, as you drive in your environment. What is wrong with having depth checks as part of the process? Something that could be used less if there are environmental cues? The video is a training exercise. There's the convenience of having a reef below, but the training could be for out in the blue.