Shooting a bag (DSMB) in strong current conditions

[Macan]

She did the L-line sweep after replacement of regulator in her mouth. If you hold the spool out in front of you, the current has to be extremely, extremly strong to get the line anywhere near the regulator. I'll keep it in mind though.

Hi @CWK. Note the line angle on the pic below (4:03) and how close the DSMB line is to the Regulator first stage and tank valve. Depending on the diver's hand placement, the line can potentially touch the tank valve or first stage and snag it. Furthermore, inexperienced divers have a tendency to float up as they inflate their DSMB. Then, they angle and swim down to correct their depth. In a moderate to strong current situation, the downward swim to correct for depth can put the line angle closer to the tank valve. I've seen this too many times .

Good discussion. If you travels take you to the Philippines, look me up and let's do some diving .

 

[CWK]

If you travels take you to the Philippines, look me up and let's do some diving .

Might be sooner than you think. Where are you located? I've done SSI Extended Range Nitrox and was thinking of maybe doing Tec 40, 45 & 50.

 

[Macan]

Might be sooner than you think. Where are you located? I've done SSI Extended Range Nitrox and was thinking of maybe doing Tec 40, 45 & 50.

I'm located in Metro Manila. We dive at Anilao, 2.5 hours away. Anilao is one of the world's top dive destinations . Taking Tec is not easy and requires hard work. But it is very satisfying and fulfilling. You come out a different, more precise, safer and a much better diver overall. It's a great program to take even if your diving is recreational .

 

[Pearlman]

Would it be better to face the other way 180 degrees (with the legs into the current ) so the dsmb line does not lean over the 1st stage but away from the diver? I like the L-technique of smoothing out the line - I found the spool nearly slipping out of my hand with a jerk (in fact it did and I had to retrieve it once). So I am now wary of deploying it like in the 2nd video with one hand and let it shoot straight up. With the L-technique I think might be able to control the unspooling and make it smoother without jerking out of my hand. I bought a 6ft semi open dsmb not knowing better and rarely practice deploying it.
But this thread reminds me to .. from my next vacation ... Thanks!

P

 

[Macan]

Would it be better to face the other way 180 degrees (with the legs into the current ) so the dsmb line does not lean over the 1st stage but away from the diver?

Yes you can but that would mean you will be drifting with the current. Unless of course your reverse (backwards) kick is so good and strong that you can hold position .

You can keep your 6ft DSMB folded in your backplate for surface deployment. It stores well in the BP and can be quickly retrieved with one pull. But a 3.3 ft DSMB for underwater deployment is the best IMHO.

 

[CWK]

You can keep your 6ft DSMB folded in your backplate for surface deployment. It stores well in the BP and can be quickly retrieved with one pull. But a 3.3 ft DSMB for underwater deployment is the best IMHO.

There are differences of opinion on this. My SSI Tec instructor had only 1 SMB. It was a 10’ monster. But then, he had been left behind by a dive boat before.

 

[Diver0001]

This is a video of my PADI AOW student learning how to deploy a DSMB in strong current conditions while maintaining position (vs drifting).

I thought I'd share this with the community to help new divers learn this essential skill. The video includes a step-by-step "how to" of the skill starting at 1:40.

The student in the video is learning so don't expect perfection . Also, the video was shot in real world conditions (strong currents while on a safety stop) vs. a photo shoot in a pool or perfect ocean conditions . Watch it in HD to see the details of the skill.

I hope this helps someone.

This is outstanding. I can understand why you are proud of this.

Personally I'm not a big fan of orally inflating the blob but then again we usually dive in drysuits and have an extra hose readily available. You're clearly creating competent divers. Good on you.

R..

 

[CWK]

Here's a different version that I found online that I quite like.

 

[Magnus Lundstedt]

It could also be because their boat crew would be looking for them in that direction. Also, re the unfurling, helps with a smooth execution of the process.

On most boat dives I been on, The boat stays in one place and You have to go back to the boat. If you drift away you get a long surface swim back. Better to do your SS close to the boat and in a place where you have references like close to the reef.

 

[Diver0001]

OK I need to ask..... why do so many divers see a need to attach the spool to the blob during the launch?

In 30 odd years of diving I've literally never done this. To me it seems like a waste of time and energy. I attach the spool to the blob before the dive and it's all one unit when I want to launch it. I see ZERO added value in delaying this until we want to launch the blob.

comments?

R..