using a reel for SMB release?

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Solly

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Last week I had a dive where it was my first time to try to release my SMB connected to the reel while being on the safety stop.
I did that before but the SMB had its own string, so it was my first time to use the reel.

Should I restrict the reel to 5m where the SMB is just above me? this was not possible as there was a strong surface current and waves that drifted the SMB away, so I would either follow underwater or just surface or allow the SMB to go and give it more reel length....

Any thoughts what should be the best practice in such case?

What about just inflating the SMB when I am already on surface hence do not need any string attached to it?

Thanks
 

Mike Boswell

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I am also an SMB Neophyte, having shot my SMB exactly twice. And it is amazing how many things there are to know about using one. In my mind there are many different uses for the SMB.

To tell your anchored dive boat where you are and that you are beginning your safety stop.
To tell a following boat on a drift dive where you are and that it's time to come pick you up.
To warn other boats that you are there and ascending, so they won't run over you.
To establish a vertical up-line as a physical or reference aid on stops or ascents.
To signal that you are in trouble and need help.
To help rescuers find you if you are lost at sea.
To provide a second source of buoyancy.

I'm glad you asked this question, and I am looking forward to learning from the pros.
 
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TSandM

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The time to release a bag depends on what you are trying to do with it. Shooting a bag from depth gives the dive boat the earliest possible information on where you are. This is important if you know you are not where you are supposed to be. (We got into very heavy current on a dive last weekend, and knew we were being blown off, so we shot a bag the moment we thumbed it.)

If you believe you are where you are supposed to be, or if you are doing a live boat dive where the boat is supposed to be following you, you might not shoot a bag on ascent, but inflate it on the surface, if the boat has failed to follow you accurately. Personally, even in this case, I like to shoot it from depth, so the boat has plenty of time to pick it up and close the gap. Nothing like surfacing and seeing it right there!

As far as wind and current go -- both will drag a bag away from you. I haven't been in conditions where that drag was so strong that it pulled me off my depth at a stop, but I can imagine it happening. In that circumstance, you would have to release line and let the bag get further away from you. Most of the time, the line will go up at an angle, but the vertical vector on the pull will be small enough that you can maintain a stop while hanging onto the spool.
 

hg frogman

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The DSMB (D for delayed : you send it at the end of your dive) tells the boats around (including yours) where you are. It can be a life-saver. Notably when the place is crowded with boats (common in Egypt). In my opinion, it's a mandatory piece of kit, at least for drift or "serious" diving (take also a small LED torch with several hours of burntime, like this the boats looking for you after your wild unplanned drift are almost sure to find you eventually ... at night !)

For me, though it's doable, it's not such a good idea to inflate it after you surface, unless you are so close to a reef that even the zodiacs cannot come close and harm you. The DSMB is here also to tell all boats: stay away with your nasty propellers, there are divers below. So send it from your safety stop, or even before. Typically, a good captain on a Red Sea boat expects to see your DSMB 5 to 10 minutes before you surface. Like this, he knows where to pick you up in time.

You can use a DSMB with a reel (or a spool) ; or without, with only some line wrapped around the DSMB and hold by bungees (I use a SS carabiner at the end of the line to weight it, with two bungees on this carabiner ; I wrap the line around the SMB, use the bungees to tighten it all, and clip the carabiner on my D-Ring ; I deploy the entire line for use and the carabiner acts as a weight. I use also a finger spool for deco dives).

In that last case, because of potential surface current, the length of line must be greater than your deployment depth. Eg if you send the DSMB at 5 meters depth (= safety stop) it's good to have 7.50 meters of line, in case. The cheap line usually sold with DSMBs is not any good, replace it by some decent 2 or 3 mm line like those from climbing accessories. A drawback of this no-reel way is, you need a bottom not too shallow (12 to 15 meters minimum) so the line, that you're fully deploying before sending the DSMB, doesn't get entangled on the bottom ; usually not a big problem, at least where I dive.

Using a reel (or a finger-spool, less bulky and simpler) gives more possibilities but it's another item to carry. Also take care with spools, the carabiners (with two slipping gates) usually sold with them are prone to get unclipped while jumping from a zodiac, etc ... so I suggest you double them (= use two carabiners parallel to hold your spool) or find your own way to do it safely.

Tech divers often send a DSMB from the bottom (= beginning of their ascent) to tell where they are and to have easier control of their ascent speed. But that's another story, rec dives are usually multi-level and for these dives one often doesn't need such a long line (apart from some special circumstances that Blackwood details below and that make a reel or spool with enough line really handy).

After your DSMB is on the surface, you swim underwater where you want, while pulling on it - like a dog on a leash. It's normal that sometimes, with surface current, the dog is a bit hard to master. You give leash or you take leash depending on the current, but usually it's not so strong that you cannot stay connected to your DSMB while doing your stop.

DSMB deployment needs some practice to be done properly and safely. Check around you to have some demonstrations - and then practice - if you feel not completely at ease with it.
 
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Blackwood

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I prefer to keep my hands as free as possible (to hold my light, my camera, my scooter, etc.). So unless I'm doing a drift dive in which the boat has to follow me throughout, I am unlikely to shoot until I'm ending the dive.

At that point, there are a few considerations.

1) WHY am I shooting? Is it to give me a vertical reference? Or is it to give someone on the surface information?

  • If for my own reference, I'll generally wait until it's convenient. If I'm doing 1 minute stops down deep that eventually get longer, I'll hold off until the first longer stop. If I'm doing 1 minute stops all the way up, I'll still generally wait until I'm relatively shallow (in case I fumble with my pockets, with the spool, etc., so that I'm not overextending my deep stops). If it's because I'm in heavy current and need to do a free ascent but don't want to get blown all around the ocean (anchored boat situation), I may elect to tie into structure on the bottom.
  • If it is to give someone on the surface information, what info? Is someone hurt and I need in water assistance? If so, I'll shoot ASAP. If it's for a boat to track me, I'll consider the situation. In current, I'll shoot ASAP (before I get out of surface visibility). Same story in heavy chop or other poor surface conditions.
2) How much line do I have? You're going to want more line than depth.
3) The shallower you are, the more air you have to blow into it. From 10m, I have to fill it halfway, but from 30m, I only have to fill it a quarter of the way.

etc.
 

rjack321

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As far as wind and current go -- both will drag a bag away from you. I haven't been in conditions where that drag was so strong that it pulled me off my depth at a stop, but I can imagine it happening. In that circumstance, you would have to release line and let the bag get further away from you. Most of the time, the line will go up at an angle, but the vertical vector on the pull will be small enough that you can maintain a stop while hanging onto the spool.

Dump gas and pull down so the SMB stays roughly over you. Otherwise the line will in short order be going sideways and no longer marking your position (and the boat may end up circling over your exact spot - not so good when you get shallow).
 

Van Isle

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Dump gas and pull down so the SMB stays roughly over you. Otherwise the line will in short order be going sideways and no longer marking your position (and the boat may end up circling over your exact spot - not so good when you get shallow).

Not always reasonable. If I'm at 600psi and ascending I don't have enough extra air in my wing to dump to "haul down" on even a 6 lb lift SMB. It is necessary to understand that your SMB may not mark your exact location, but as you ascend up the line to surface you'll be close to the buoy. There are other reasons to let the line run out in addition to heavy current/wind at the surface. My SMB got snagged by a "sweeper" log on a drift dive this weekend. I let the spool run and eventually the log ran over the SMB. As I spooled up on ascent I surfaced next to the SMB with the boat waiting. I had had no idea what had happened, but I can tell you I knew where my knife was!

VI
 
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