Visual reference on anchor line

[BlueTrin]

I have done both anchor and drift dives. I understand the limitations of both. However I have a specific question about drift diving in strong currents in bad vis on a wreck.

It seems extremely dangerous to be drifting into dangerous structures at a high rate of speed when you may be disoriented and smashed into structure or even ropes, lines etc. I had a drift dive once where I was drifting sideways and had big beam just mis my head in deep dark water. I question the wisdom of always drifting into a wreck.

In the U.K. on the channel the tide is quite strong, you dive wrecks usually at slack water, then the tide picks up and you usually leave drifting when the current has picking up.

 

[Celt]

In the U.K. on the channel the tide is quite strong, you dive wrecks usually at slack water, then the tide picks up and you usually leave drifting when the current has picking up.

A shot with a station that can be set adrift is handy in current,

 

[BlueTrin]

A shot with a station that can be set adrift is handy in current,

Yes for longer decos people use this setup, I think @Wibble mentioned it too.

When everyone is on it, they’d usually let it go to drift.

 

[Celt]

Yes for longer decos people use this setup, I think @Wibble mentioned it too.

When everyone is on it, they’d usually let it go to drift.

Ye get a lot of traffic so there’s that too. Nothing is perfect for all situations .

 

[Pavao]

Yeah, I don’t see how those other strategies have advantages over drift deco, both in comfort and safety.
The closest I get to it using anchor line is when the last diver pulls it off the wreck and everyone drifts with the line, which is attached to a big float ball at the surface, that way at least those comfortable holding a stop can let go of the line and just drift alongside it and not be in the middle of a clustersuck of divers at the 30’/20’/10’ stops, but, often divers screw up the process and the last diver never releases the anchor line from the wreck. Seen it many times working/diving here in SFL.

And let’s be honest, using anchor line for both up and down are almost always a result of either a request form those not comfortable without it, or the captain trying to eliminate screw ups from the (known) divers who can’t follow some simple drift deco procedures, which can both be resolved with better practice/training.

 

[Wibble]

A shot with a station that can be set adrift is handy in current,

Is the term "lazy shot" commonly used for that setup?

Also need a tagging protocol where divers clip a personally identifiable "tag" just on the lazy shot side of the shot line. As they descend, they clip their tag on and remove it when they ascend. When you ascend, remove your tag and if there are no other tags, you are the last person and you must release the lazy shot from the main shot line on the wreck (there’s a quick release shackle) whilst everyone above you breathes a sigh of relief as the current stops as you all float downstream.

Additionally, it is normal to attach a good, bright, and powerful strobe about 10m/30ft above the wreck on the shot line. Lower if the visibility is crap.

Kind of odd to look up and see the flashing disco lights above you. Also when there's only one left... you're the last on the wreck.

 

[Celt]

Yeah, I don’t see how those other strategies have advantages over drift deco, both in comfort and safety.
The closest I get to it using anchor line is when the last diver pulls it off the wreck and everyone drifts with the line, which is attached to a big float ball at the surface, that way at least those comfortable holding a stop can let go of the line and just drift alongside it and not be in the middle of a clustersuck of divers at the 30’/20’/10’ stops, but, often divers screw up the process and the last diver never releases the anchor line from the wreck. Seen it many times working/diving here in SFL.

And let’s be honest, using anchor line for both up and down are almost always a result of either a request form those not comfortable without it, or the captain trying to eliminate screw ups from the (known) divers who can’t follow some simple drift deco procedures, which can both be resolved with better practice/training.

Every season without fail the RNLI are launching to search for divers using drift deco that get separated from the surface support You can’t have boat cover for multiple divers without multiple boats in any kind of sea or current. So yes drifting is the ideal way to deco but not separated. A drifting diver is a diver out of control at the mercy of the current and surface conditions.

 

[Wibble]

Every season without fail the RNLI are launching to search for divers using drift deco that get separated from the surface support You can’t have boat cover for multiple divers without multiple boats in any kind of sea or current. So yes drifting is the ideal way to deco but not separated. A drifting diver is a diver out of control at the mercy of the current and surface conditions.

In reality, it’s not that bad but does depend upon the location and conditions. Also the length of the decompression schedule.

On the UK south coast it is normal for divers to come up under a SMB. It is very rare to use a lazy shot on the south coast (I’ve personally never used one in years of diving all along the south coast). Divers are rarely lost -- haven't heard of one go missing although it must happen.

In poor surface visibility conditions, such as fog, a skipper may demand that everyone comes back up the shotline. Often this command is accompanied by a strong recommendation that everyone lines off from the shotline (tie off a reel or spool from the grapnel anchor and run around the wreck, sometimes back and forth to the shot). Most wreck divers take a spool or reel with them anyway.

Diving deeper wrecks out of more remote locations such as Malin Head (north west Ireland, world class wrecks and diving conditions), basically diving offshore in the Atlantic Ocean on 60m+/200ft+ depths it is common to use a lazy shot simply as it is safer to keep all divers in one place as they do their "hours" of decompression. If someone has a problem, needs to bail out, whatever then there's all the other divers around them to provide assistance and lots of spare gas.

There are other Scottish locations where the lazy shot is normal protocol for technical diving.

 

[Wibble]

I am not sure if divers affecting the lively hood of fisherman would go over very well, LOL. (Not laughing at you... at the idea of a dive boat telling a fishing boat that was probably there 1st they had to move). I think we respect the fact they they are there to earn a living and we're just there to play.

I think that the fish like the wrecks too and that's why they hover over the wrecks.

Just to pick this one up again.

Fishermen come in different guises. The commercial fishermen who trawl/drag for a living don't go near wrecks -- or need divers to remove their nets when snagged on wrecks. Often those fishermen are the ones that know where all the wrecks are. These fishermen know the sea protocols and a dive boat with divers below will be avoided; the dive boat should have identified itself as in diving operations using AIS; also flying a flag.

Recreational fishermen, as in rods and lines from a boat, have to work with divers; it's one or the other on a wreck, whichever boat got their first gets that wreck. Them's the rules. Obviously with the UK south coast there's more wrecks than boats (as in thousands of wrecks), so we/they would divert to another wreck if the target wreck is "taken".

Example of wrecks on a 30 nautical mile stretch of UK south coast:

WRECK WRAK EPAVE WRACK PECIO

wreck, wreck database

www.wrecksite.eu

 

[Celt]

In reality, it’s not that bad but does depend upon the location and conditions. Also the length of the decompression schedule.

On the UK south coast it is normal for divers to come up under a SMB. It is very rare to use a lazy shot on the south coast (I’ve personally never used one in years of diving all along the south coast). Divers are rarely lost -- haven't heard of one go missing although it must happen.

In poor surface visibility conditions, such as fog, a skipper may demand that everyone comes back up the shotline. Often this command is accompanied by a strong recommendation that everyone lines off from the shotline (tie off a reel or spool from the grapnel anchor and run around the wreck, sometimes back and forth to the shot). Most wreck divers take a spool or reel with them anyway.

Diving deeper wrecks out of more remote locations such as Malin Head (north west Ireland, world class wrecks and diving conditions), basically diving offshore in the Atlantic Ocean on 60m+/200ft+ depths it is common to use a lazy shot simply as it is safer to keep all divers in one place as they do their "hours" of decompression. If someone has a problem, needs to bail out, whatever then there's all the other divers around them to provide assistance and lots of spare gas.

There are other Scottish locations where the lazy shot is normal protocol for technical diving.

RNLI call-outs are logged. Because something is normal doesn’t make it a good idea. If you take a simple 40m dive to a wreck or reef 80m long from a small boat carrying 3 pairs of divers dropping down a shot and climbing an smb while drifting. If they don’t shoot within 10 minutes of each other they could be 200m apart in 1/2 a knot of current. The boat can only go to one pair and by the time they’re picked up In any kind of sea the others are out of sight and a search is on. Just because they’re found most 99% of the time they’re still lost until they are located.