[Paul Oliver]

Imported post

Hi all,

Missed the stuff on D-Net but i have to side totally with Andy on tieing off. Having listened attentivly to the Incident briefing at the BSAC Diving Officers Conference (DOC) last year and reading the report from cover to cover, mid water DSMB deployments appear in far to many. As Andy states "Its a lifting bag and only going up".

Tieing off has to be selective, but we tie a shot off all the time and know what to look for and lift/air in should be relative to depth.

As for damaging wrecks with a DSMB, you should see what can happen when i'm pulling myself along one against a strong current (about every 3rd dive).

I teach each method quite regularly and we use the tieing off as a warm up as its so easy and SAFE. Mid water is practiced a lot as it is more difficult, but practiced in controlled environment. Why take risks?

I also nearly lost 2 divers into the shipping lanes ones 'cos they sent their bag up too late and i missed seeing it. Luckily our other boat spotted it. 6m is a nasty depth to bump into a cross channel ferry.

At the end of the day its what works best for you, but i'll stick too easiest and safest.

Dive Safe and Progress,

Paul

PS If anyone dives the Eidsiva in the near future please look out for my very nice DelaydAid DSMB, which is on her somewhere.

 

[steve-k]

Imported post

<font color='#000080'>obviously tying off is a safer option, and i think it is best to show newish divers this option as they are less likley to cope with a situation


personally i would never tie off as i am confident i can deploy my dsmb from the wreck or mid water (i use a gas bottle dsmb)

this is one of those where there is no right and wrong, you do what you feel best for you, tying off is safer, but more impractical and more time consuming


if your at the end of a deep dive spending 3/4/5 mins finding a sutable tying off point, attaching and deploying, then un attaching, can rack up your deco fast and quickley use up your air


last year on a 55m dive we had justed bagged up the porthole, exceeding our wort case planning, lol, my budy left the wreck deck (50m) with 20 bar, i had about 35bar, deploying our dsmb from the wreck just wasnt an option, and as we had 40 mins of deco to do we needed them more than ever

oh and befour i get 30 replys slaging my stupidity off for geting into that situation, i had bress fever  lol, jk, it was a bit silly, but we both had side slungs on for the deco and extra redundancy

 

[Digger]

Imported post

I knew we'd find someone! Proof at last that mayb we shouldn't be encouraging newbies to be doing this. There is quite a lot of lift in an SMB, and I knew someone would have done it. 10/10 for effort. Did someone offer to sign you up for a S&R Spec after?

Other one is I know the permanent shot is bad for the wreck too, but just because we do one, doesn't mean we have to do both.

 

[ANDY 64]

Imported post

To make a few of my points clear and a little story of a DSMB incident i saw,,

Seeing the word TIEING OFF, Does this mean that you lot use a piece of line and tie endless amounts of grannie knots from your wreck to to reel ?


My method is that when ready for deployment, i find a strudy bit of metal that i can deploy from,,, reaching into my drybag thigh pocket i pulled out 1 mt lenght of 1" webbing that has a snap hook on each end... snap one hook to the ring that is on my reel,,loop webbing back on it self after making a endless loop around fixed metal....add air into  dsmb and let fly via reel trigger,,,,,, when line goes slack ( after Dsmb hits surface ) release trigger. undo one clip from reel and begin to go up.


STORY TIME that at the time was funny from what i was seeing , but resulted in the chap having 6 hours in the pot.

I was diving solo on a wreck at 42mts, when i came across a pair of divers, one of them had lost his Dsmb and reel on the wreck during the dive ( this came out later at debriefing ), the diver who was trying to  deploy his Dsmb with a slight bit of tide running ( behind him was the shot line about 5-6 mts over his left shoulder, to which i was going back to when i came across them, anyway, this diver was sat on a deck beam with his legs wrapped underneath and crossed, to try and stay in one place, i saw him remove his reg to fill his dsmb, next thing reg had got caught in the opening of the bag, a small bit of a wiggle and his legs came away from the deck beam , taking him to the surface at a very high speed ( there was nothing i could do to help at this time ),, it did take him all the way to the surface..


On looking at his kit, he had his reel on one clip , clipped off to him on his left shoulder D ring, with a small lenght of 10mm line with another clip on it , clipped on to a D ring on a pull strap of his stab jacket right side,there is no way that i could have got them 2 clips of at that speed , let alone him while trying to get his DV back in his gob,

After seeing this , i will always deploy from a wreck after reel has been secured and dsmb is on suface.

If my reel jams, ( never , but once fell apart ) , i cut line and free ascend.i have only done mid water deployments when on a nitrox course, and won't do one unless in a emergency.


Andy

 

[Gimbo]

Imported post

<font color='#0000FF'>You probaly think I'm an idiot but I'm going to ask this anyway-
What is the point of tying the reel? Is it because if there is a jam you don't risk a uncrottoled rapid ascent? also not hence not loose your reel and SMB?

I ask this because since joining YD I've began using an DSMB and now do not dare not taking one. However I don't tie the reel to anything, then my dives are relatively simple and rarely do I dive wrecks. I've been learning with practice, so far my biggest mistake is my octopus getting caught on the strap of the SMB and I jumped a couple of metres before untying myself. This happened at 15m and there was no need to use the SMB as such ( but doing it to practice and learn from such mistakes.)

When would you realese the SMB in mid water? I would have thought one always releases when at the bottom. The only time I can think of is to avoid releasing precious on a deeper dive.

 

[Finless]

Imported post

Quote[/b] (Chris Guimaraens @ July 17 2003,13:16)]What is the point of tying the reel? Is it because if there is a jam you don't risk a uncrottoled rapid ascent? also not hence not loose your reel and SMB?

Chris,

There is no argument that as a specific act, tieing the reel off and releasing the DSMB is safer than doing it from mid water. That is not to say that all of us should be able to send one up from mid water.

Losing the reel is not a worry as my life is worth more than.that

There are other considerations, as has already been mentioned, about using up bottom time and poss over running your time at the max depth. Also, by always sending the DSMB up from a tied off position you run the risk of getting out of practise doing it from mid water etc.

Your own comment abt practicing deploying a DSMB and being pulled up a few mtrs is an indication of what CAN happen and apparently BSAC statistics show it happens too often.

All I can say is I prefer the tieing off method but when required I can do from mid water - usually on the second dive when the skip wants the bags up after 20 mins on a drift. I would thouroughly receommend to anyone the DSMBs with the refillable inflation bottles. Not only are they easier to deploy, you can guarantee they will be properly inflated on the surface.

However you do it, may your blob always be there to greet you but never take you there with it.

 

[Dominic]

Imported post

Quote[/b] ]When would you realese the SMB in mid water?

Main occasions:

You're coming up from a deep dive and you don't want to reel in masses and masses of line

The SMB already up is lost - buddy separation / SMB deflates / line breaks / loose your grip on the shot in a strong current / etc - if you're halfway up and suddenly you need an SMB, the last thing you want to do is go back to the bottom.

 

[Mark Chase]

Imported post

Perhaps I am more critical of this practice because bottom time at depth is so important. If you do a deep dive your bottom time is limited by gas and your tolerance of deco. As a result you can end up with 20min -30 min bottom times on a dive that just cost you £50.00 in gas, £35 for the boat and £10 in petrol.

Fafing about finding a tie off spot and actualy tieing off is a time consuming and there for bad thing. also a cock up would cause extra bottom time which = extra deco comitment.

If I bag oof and it goes tits up I let go the reel and go to first stop depth and go to back up. That is the safest thing to do on a deep dive. All this getting toed to the surface nonsence is for people who think there £100.00 worth of equipment is worth the trip in the helecopter.

I made that mistake once but never again.

So all in all horses for courses. If your happy with the system and not doing extended bottom times cool. If you are then mid water / botom deployment of DSMB is IMHO esential skill.

ATB

Mark Chase

 

[John Gulliver]

Imported post

We rarely need to use, or even carry, an smb in my part of the world, so my experience of using them is limited, but I've been following the thread with interest. I think I can discern two groups here: those like Mark who do deep dives with longish deco times, who, not surprisingly, are against tying off, and those who normally dive to around the 30-35 m mark and only do short deco, if any, who tend to shoot their smb from the bottom and think tying off makes it safer. Both views seem perfectly reasonable to me. Horses for courses, as usual. Of course, everybody should be able to shoot their smb midwater if necessary, though.

 

[Paul Oliver]

Imported post

Guys

I think John (as the grown up here) has summed things up very well. As Andy has mentioned the shot is sooooo much safer.

I have done one rescue this season. If the diver i brought up had been on an SMB he would have had an uncontrolled inverted assent, albiet only from about 26m. The fact he was holding a secured shot line was enough for him to slow his assent enough for me to dump air from his BC and gain control of the situation.

Marks argument is totally sound, personally i would not want to reel in 50m of DSMB line or waste valuable bottom time and gas deploying a DSMB from that depth, but how much time does it take if you are looking for it in your last few minuets.

Mid water is a superb skills practice, but why put in risks, espesually if you have a high tissue code? Unless (As in Marks case) it is an essential part of your dive plan/technique.  As with all diving issues experience, training and personal skills are the key factors IMHO.

Regards and safe diving

Paul

 

[Rob Evans]

Imported post

In the final analysis there really is no right or wrong way to bag off, with the exception of the 'bag off at shallowest depth' argument which I have to say is totally irrelevant to UK wreck diving.
If you're doing medium depths and the current isn't too mad there's no reason for not tying off on the wreck and doing it all nice and safe- been doing it for donks and have never brought a wreck to the surface. Bit gutted about that actually.  If you're deeper and the deco/gas use is much more of an issue, then free ascend for a bit or ascend the shotline (if it's still there/you can find it) and blob off from first stop. Bear in mind, you'll want to come away from the shotline before you deploy, just in case there's somebody further up the line. If it all goes a bit Pete Tong, you let the thing go and deploy your spare. Skip'll pick it up and all you have to put up with is a bit of pisstaking on the way back.
Yes yes yes it's all very well getting sniffy about proper preparation preventing reel jams, but it happens to the best of us and there's a better than even chance it'll happen to you one day.
It's all too complicated this diving bollix.  I'm going back to tiddly-winks.  Does anybody make an incredibly expensive yellow tiddlywinks set, cos I want one.  The more dangerous the better.

 

[Finless]

Imported post

Quote[/b] (Rob Evans @ July 17 2003,23:22)]I'm going back to tiddly-winks.  Does anybody make an incredibly expensive yellow tiddlywinks set, cos I want one.  The more dangerous the better.

You had better look for some inflatable ones so you can do pressure tests prior to the game - at least you will still be able to use some of the training. As you appear to getting to the age known as too old you might as well give me your YBOD.

 

[Finless]

Imported post

Some good replies in this thread and the results are pretty even. Personally I don't mind winding in 50 mtrs of line as my reel is of the larger type plus it is a visual reference on the ascent rate - don't overtake the line and have slack forming.

I don't get below 40 mtrs very often so Mark's info on the deeper side of things makes good sense.

Not having seen the BSAC reports on the accidents caused by mid water deployment of DSMBs I wonder if the vast majority of these incidents occur to inexperienced divers or those who do not dive regularly?

We can all agree that deploying a bag from mid water is a necessary skill.

Perhaps newbies should be trained so that if they get dragged to the surface by their DSMB they should get on the boat quickly and get the tea ready asap, certainly before they get the DCI hit.

 

[msssltd]

Imported post

Quote[/b] (Finless @ July 18 2003,11:03)]Not having seen the BSAC reports on the accidents caused by mid water deployment of DSMBs I wonder if the vast majority of these incidents occur to inexperienced divers or those who do not dive regularly?

Well go have a look at the reports then;
http://www.bsac.org/techserv/increp02/ascents02.htm

Here are the references for incidents that involved a DSMB
March 2002 02/252
April 2002 02/105
April 2002 02/128
May 2002 02/196
June 2002 02/152
June 2002 02/166
June 2002 02/174
July 2002 02/189
August 2002 02/247
August 2002 02/272
September 2002 02/275

All the usual problems are represented;  line entanglement, freeflows from purge buttons, regs getting ripped out, octos tangled in straps, empty inflator bottles.  BUT only a couple are noted as midwater deployments.

Now look at the dates.  The majority of incidents happen in  the early part of the season.  I would hazard a guess that the underlying problem is lack of practice rather than lack of experience.

Personally I don't tie off, don't use a crack bottle and don't deploy while touching the bottom or wreck.

Usually I ascend a couple meters above the wreck / bottom, face downtide, two breaths in the bag, check for entanglement hazards and let the bag go.  It is exactly the same technique whether I am drift diving, diving deeper than my line, separated from a buddy, just had my blob run over by a boat, bailing off a shot line etc, etc.  Thats how I like things one simple well practiced response which works for pretty much every situation.

When deploying I never inflate to the point where the bag can drag me up.  I feel it is asking for trouble. It forces you to rush the deployment and you don't have a chance to check the line/reel is clear.  If your worried about being limp on the surface get a small secondary for shallow deployments.

Deploying DSMBs is an inherrently dangerous operation.  Treat both the procedure and your level of practice with utmost respect.  Particularly, at the start of the year don't assume that your as good as you were the previous October. Book a couple shallow drifts and practice your DSMB deployment before using it for real on a 30m+ deco dive.

Regards
Matt

 

[Finless]

Imported post

Quote[/b] ]Well go have a look at the reports then;
http://www.bsac.org/techserv/increp02/ascents02.htm

Tks for the link. No matter where they happened I presume if the divers had tied on before inflating then these accidents would not have been caused by the bag.

I am more than happy to accept that there are some times when deploying a bag from the bottom is not the best option, however, where practical I prefer to use it.

 

[steve-k]

Imported post

<font color='#000080'>hands up
who is a member of the under water nitting club?


i had a rapid asent from 40 to 3m after getting completelet entangled in my dsmb line   but i did get a go in a huge seaking???  thx tax payers

 

[Mark Chase]

Imported post

As told before I got inverted after being draged up about 5m when another gas filled DSMB hit my line and got tangled. I did a feet first ascent from about 26m to the surface but went back down got on 02 and was very lucky to avoid a bend.

I was off the wreck when this happened and was heading up to my first stop depth so tieing off isnt an issue in this case. Being stupid and hanging on to my reel was the issue.

Thank God for 02 my 6m stop was sposed to be 10mins I did 45

Mark Chase

 

[Mdemon]

Imported post

I don't usually tie off to a wreck.  I think it would be safer to do so, but I'm happy with what I do.

As far as hurtling skywards is concerned - which is the route of all evil as far as I'm concerned, I have two solutions;

1) Don't buy those ridicululously expensive dive reels everyone is so keen on.  Then you can let the bugger go rather than follow it skyward.  50m of negatively buoyant, 150Kg breaking strain nylon braid cost me around a fiver.  I use on old antenna spool - £1 army surplus.  I can always collect it from the surface later, and if I don't, so what?

2) Is the speed of deployment causing problems?  To give me time to spot probs, and just for a chilled out life, I clip a small drogue to the DSMB.  The DSMB then rises very sedately, and if something goes wrong, I've got time to react.  I do have a larger, spring-loaded drogue which will stop it dead, but that's another story...


HTH

 

[Mark]

Imported post

<font color='#0000FF'>Mid-water deployment (which is made very easy by using a Halcyon closed circuit DSMB and a spool).

I can see why people using big clumsy reels and filling from their 2nd stages may prefer to do it tethered to the wreck.

Regards,

Mark

 

[Dr Stevil]

Imported post

Quote[/b] (steve-k @ July 19 2003,00:27)]hands up
who is a member of the under water nitting club?

Sunday 2nd dive I got an unfixable jam (as opposed to a simple, fixable  snagging on the handle or similar problem) due to a design fault of my cheapie Beaver reel (fairly easily rectifiable). I just let go of it and we collected it later, no problem, both computers were clear so no harm done.

Ironically, this was only an unfixable probem due to it being a shallow water deployment (~10metres) , whereas if I'd deployed it from 20+m, as is more typical, it would have been easier to wind it back in and untangle.

either way, I've always believed that most problems can & should  be viewed as a learning  opportunity rather than being seen as a failure: system breakdowns are far more educational than perfectly smooth trouble operations.
Chee-az
Steve
PS Mdemon - what's a Drogue? sounds like something from Clockwork Orange, droogy