Technique for Shooting an SMB

[Diver0001]

Exactly how do you gracefully shoot an SMB from depth without getting dragged upwards? I have tried it about a dozen times and I'm still not happy.

I have a 6-foot Halcyon closed-circuit Dive Alert Marker that I inflate with my LP hose and send up with a finger spool.

The problem is that I start getting dragged upwards before the SMB has really inflated very much. I figure that, at 60 feet, I only have to inflate it about 1/3 full to get max inflation at the surface (66 feet = 3 ata).

However, long before I get even that much inflation I am on the express elevator upwards and I have to let the SMB go prematurely. (Okay, no funny comments here about premature releases....)

I tried exhaling just before so that I am negatively buoyant as the SMB inflates, but this doesn't work either.

The best I can do is to get dragged up only two feet before I release and end up with a half-inflated SMB at the surface. Maybe I just need more practice?

It's all about breathing, Doc.

before you start, set your buoyancy so you're neutral with lungs full. Take a deep breath before you start inflating. Then inflate. As the air goes in you breathe out. When your lungs are empty you let go.

R..

 

[Kevrumbo]

Have your Buddy help stabilize & keep you steady at depth, from a horizontal position slightly above & behind by pushing down on you as you're inflating the SMB.
Be sure to consciously release the bag up, out and away at armslength to avoid tangling yourself and your Buddy. . .

 

[jagfish]

Hmmm...I don't think I'd want to depend on my buddy to help launch a bag...except in extraordinary circumstances...

 

[Rick Inman]

I got my reg clip hooked on the line once and took a ride. Not fun.

Once I discovered (read: was taught) that you don't need to fill the bag - you don't all much air at all - it became easy. Get a little neg, give it a little squirt or one normal breath, maybe fin down a bit, exchange OKs with your buddy, look up, then let 'er rip! No hurry.

Oh, and keep your line tight until you release! :11:

 

[Kevrumbo]

Hmmm...I don't think I'd want to depend on my buddy to help launch a bag...except in extraordinary circumstances...

Extraordinary circumstances like shooting a SMB in heavy current, or severe upwellings/downwellings while holding a Deco Stop: Having your Buddy help is Standard Operating Procedure that was taught in Adv. Nitrox/Deco Procedures Class. Even in benign conditions, the technique still helps facilitate a bag launch. . .

 

[Green_Manelishi]

Have your Buddy help stabilize & keep you steady at depth, from a horizontal position slightly above & behind by pushing down on you as you're inflating the SMB.
Be sure to consciously release the bag up, out and away at armslength to avoid tangling yourself and your Buddy. . .

So when you let go the bag you and your buddy are now likely negative and your buddy is in a position he can't be seen by you. Peronally, I don't want my buddy hovering over me and pushing down on me. When "shooting the bag" gracefullness takes second place to effectiveness.

 

[Kevrumbo]

So when you let go the bag you and your buddy are now likely negative and your buddy is in a position he can't be seen by you. Peronally, I don't want my buddy hovering over me and pushing down on me. When "shooting the bag" gracefullness takes second place to effectiveness.

No. . .the "pushing down" technique involves dynamically modulating/manipulating the force needed to keep both you & your Buddy at a constant depth. It's really very simple: Just help hold the Bag Shooter steady at depth. . .

 

[Mambo Dave]

I haven't done this, but one arm on their backplate strap sounds effective - the buddy does not need to be above the shooter.

 

[Green_Manelishi]

I think a better idea is to be able to deploy your bag without any assistance; especially someone "assisting" you in remaining at a constant depth.

 

[Kevrumbo]

I haven't done this, but one arm on their backplate strap sounds effective - the buddy does not need to be above the shooter.

The Buddy is basically a "Wingman" to the Bag Shooter, a steadying hand on the back of the Shooter's Tanks is all that's needed to help hold him at depth in benign/calm conditions. In rough conditions, or if the inflating SMB is starting to pull up the Shooter, the Wingman may have to anticipate and adjust to be slightly above --gaining better arm leverage to keep the Shooter at depth.