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> > What do you do if the line catches again on the ground ?
> 
> Chances are it won't hang anything significant on a sandy bottom (which is
> the case for most deep sites). The force in a high current can be quite high
> and will pull loose most obstructions if it does.


Well you may have mostly sandy bottoms over there. 
I once saw a small chain get snagged into a little gap on a little rock.
It's still there. A commercial diver saw this and said,..blast the
rock...

So if you take a snagged line into account, you also do for an ascent in
the current as opposed to drifting. Only then you are obliged to leave
the downline attached. 

When I understand correctly, your method is similar to ascending from a
shotweight line, which is also released at the end of the dive from the
wreck, but heavier, and will provide less drifting

Only a well placed shotweight will sit in the wreck while divers drift
into it from upstream, whereas in your example it depends on the driver
who leads the line. So if they miss, all miss.

Matthias

 Of course if it is another
> wreck then consider yourself fortunate and deal with it. That's why you have
> liftbags and a captain with a clue. The captain will know the upline has
> snagged and will see the liftbag(s). A no-brainer.
> 
> > If I understand correctly, this "one diver with the chain end", will he
> > have a buddy ?
> 
> Definitely.
> 
> > Does he hold to the end, or just follow ? In case b)
> > everyone can follow. In case a ) he is obviously more negtive than than
> > the rest.
> 
> Holds the end. The idea is to tie the line end into the wreck. Hey the chain
> ain't a ton as it only provides something that can be attached to a wreck
> and not be frayed, and will give a little deadweight on an upline! Sure he
> will be more negative but a properly weighted diver will have sufficient
> reserve buoyancy. If the diver is properly weighted he and everyone in the
> team will have no problems staying together. Anyways the trick in a high
> current is to drop relatively fast so you can drift into the wreck and not
> miss it. If you fart around you will miss it every time. 'And you may
> anyways on deep drops as the bottom currents can be significantly different
> than the top at least in near-coastal Florida (e.g Ekman motion from the
> Coriolis force, fetch, duration, upwelling, longshore drift, etc.).
> 
> >What, if he has trouble equalizing ?
> 
> Then he's a wuss and deserves to be picked up by the boat and miss the dive!
> Think, a properly weighted diver will be in control.
> 
> > Maybe I did not understand the full context, so please feel deliberate
> > to explain a bit more.
> > regards
> > Matthias
> 
> Take care,
> Doug
> 
> >
> > >
> > > > Just for thought:
> > > > Upline with sufficient but not exceessive scope, redundant surface
> > > > floats, and bottom chain with snap/hook. Down rig with divers is
> > > > dropped ahead of wreck to drift into wreck (one diver in team drops
> > > > with the chain end). On end of dive last divers detach chain from
> > > > wreck and toss into sand. Proceed up line. Now the line is drifting
> > > > with the current with a slight bottom drag from the chain. No flag
> > > > flying. No issues. Relaxing. The boat is always free to maneuver. If
> > > > too crowded on line, you can hover alongside or pop a lift bag
> > > > nearby. Will still drift the same as main upline with a slight
> > > > backpeddle to compensate for chain drag on main upline. The captain
> > > > on the boat knows where everyone is; can drop a safety diver on you
> > > > if appropriate and recover used stages. Its a piece of cake and
> > > > works well in raging currents like we can have in the gulf stream
> > > > (and with close to shore shipping as well). A slight mod on deep
> > > > stuff (350+) though, and you need a captain with a clue.
> > > >
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