Visual reference on anchor line

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They all do come up at roughly the same time; the boat follows the field of SMBs.

The skipper would tend to put in the people doing the longest dive times first and the shortest dive times last. As each diver gets to the end of their dive time on the wreck they throw up their SMB and ascend, doing their deco as their float from the wreck.

What if your group of divers drifts into a fishing boat? They're everywhere over here.. I just can't see that working better then coming up the anchor line (here anyway).

There is a line ran from port to bow with a weight... plenty of room to spread out.

I'm not saying there's not other ways to skin a cat... I'm just saying that in my very limited experience I don't see that working here... but I've also been proven wrong plenty before!
 
There are exactly zero circumstances under which a thinking diver would consider being attached to the anchor line in a current as a correct way to dive. If that seems like the only available approach then the correct option would be to not dive in the first place.
Ah, so you know the "one true way" to dive and anyone who doesn't agree with you is stupid.

Got it. It's the internet.

Coming back to the real world, charter boats mooring to wreck sites is extremely common. Sometimes there is current involved. Sometimes a little current going down turns into a lot of current by the time you go back up. And before you say it, obviously anything taken to extremes becomes ill-advised. And ridiculous.

Going back to the OP and not this silliness, I would suggest not using a clipped on reference. It adds complexity and anchor lines can move up and down as the boat responds to waves, making it a poor reference. I find keeping one eye on your computer during gas switches and deco in general is the safest approach, albeit one demanding some concentration.
 
There is always the possibility you'll come up to less then stellar currents in that case I guess we should just all find another hobby in this area? :) Crochet?
If you're going to do a drifting ascent then it doesn't really matter how strong or variable the currents are (as long as your scooter can get you down to the dive site in the first place). During the ascent you drift with the current while the boat follows you on the surface.
How on earth would a 1" piece of webbing come undone? Have you seen that... or just think it could happen?
It's more likely that the diver will just fumble the attachment at some point. Or due to an emergency or navigational error they may have to start ascending before returning to the anchor and thus never have a chance to use that 1" piece of webbing. Since a drifting ascent is always possible it's safer and less stressful to just always plan for that from the start rather than attempt to stay on the anchor line.
Can you site one case anywhere that someone wasn't able to successfully use a jon line and was harmed in trying?
I am aware of one such case. Although the divers involved weren't exactly harmed, they were lost on the surface for a couple hours. This was one of the incidents that caused our local community to stop doing tech dives from anchored boats and switch to drifting ascents with SMBs.
What would you do if you came up to a roaring current out of nowhere? Hold on for dear life? (Honest questions)
I would not hold on for dear life. If there was any risk of a strong current coming up during the dive then I would plan a drifting ascent from the start, and ensure that the boat crew understood that plan.
I'm not sure what the average viz is in California, but here you're lucky if you see anyone on the same wreck in the NE... how would all those people begin to ascend and drift at the same time? That sounds like an absolute cluster fck in these conditions.
Visibility in California is highly variable: sometimes 100+ ft, sometimes near 0. When we have multiple teams in the water we synchronize times so that each team starts their ascent and launches their SMB at roughly the same time. And even if one team has to end their dive early the SMB will still pop up close to the boat so that it's easy to track everyone.
 
What if your group of divers drifts into a fishing boat? They're everywhere over here.. I just can't see that working better then coming up the anchor line (here anyway).
The skipper will sort that out.

The skipper will use the radio to tell the fishing boat to change course including calling the Coast Guard to resolve the issue, if not will use the boat to protect the divers below as the fisherman will be deliberately endangering life.

Fishermen cannot fish for divers! That's illegal, and they don't taste very good with all that rubber.


There is a line ran from port to bow with a weight... plenty of room to spread out.

I'm not saying there's not other ways to skin a cat... I'm just saying that in my very limited experience I don't see that working here... but I've also been proven wrong plenty before!
The problem then is the dive boat is now not able to run its engine as there's divers below the boat.

Unless you're talking about tying the boat onto the anchor/shot line. How does that work in 2 or more knots of current? That's bloody uncomfortable for divers. I guess in locations with little or no current then a fixed line is possible. Certainly not a general rule around the world -- nor around the US -- as currents vary massively.
 
To the OP, in my view, if a diver wants to do tech diving, they must be able to manage uncomfortable situations. You have cave experiences, so I bet you agree with me.

So imagine that, for whatever reason, you need to ascend far from the anchor line in the blue. This can be a planned situation (which you wouldn't do if you don't feel comfortable with it) - or an unplanned one (which you must manage if it happens!). Besides ensuring safety for your teammates, if any, the first things you want to do are:
(1) Reach your first deco stop and hold the position for the required time, but remember, you have no reference.
(2) Do the gas switch(es), if necessary, for which you need to hold your position again - without any reference.
(3) Take your SMB and shoot it; again, you have no reference.
Depending on the depth and time on the bottom, the order of the three actions mentioned above may change. Still, scenarios where the SMB is the last thing you do are quite possible, especially if you are diving deep and you need to reach an alternative gas source quickly.

The way I see it, I prefer never to use references, just to avoid becoming dependent on them, in case I need to manage a situation where I cannot have them... but that is just me
If you haven't done deco in open water then I strongly recommend practicing ascents and gas switches on shallow dives first before doing any real tech dives. You need to be comfortable doing everything without a fixed reference such as an anchor line because it might not be there during an emergency. The GUE Tech 1 course is a great way to learn those skills.


You don't need to constantly keep an eye on your computer, but there's nothing wrong with taking frequent glances; don't get fixated on it. You should be able to feel minor depth changes in your ears. Your buddy should provide a stable visual depth reference for you while you switch gasses or deal with other issues. You can launch an SMB and lightly hold the spool.
I appreciate the perspectives. Definitely wouldn't hurt getting some more practice ascending with an SMB and on a line before doing serious dives.
 
What if your group of divers drifts into a fishing boat? They're everywhere over here.. I just can't see that working better then coming up the anchor line (here anyway).
You always need to have a contingency plan. Despite your best intentions you might have to start ascending away from the anchor line, or get blown off it at some point. So, what do you intend to do in that situation? You guys need to think these things through and not put yourself into situations where a single mistake or failure could cause serious dangers.

There are many fishing boats around here as well. If we see fishing operations over our intended dive site then we either wait until they leave or shift to an alternate site. During the dive, the dive boat should be flying an Alpha flag (limited maneuverability) and as I understand the rules of the road that gives priority over fishing boats. If necessary the dive boat crew can warn off fishing vessels via VHF radio or loudhailer (or even physically moving to block another boat as was necessary in one case). This is what I meant by making the dive boat captain part of an integrated team; for tech diving they can't be just a taxi driver.
 
The skipper will sort that out.

The skipper will use the radio to tell the fishing boat to change course including calling the Coast Guard to resolve the issue, if not will use the boat to protect the divers below as the fisherman will be deliberately endangering life.

Fishermen cannot fish for divers! That's illegal, and they don't taste very good with all that rubber.

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.

Unless you're talking about tying the boat onto the anchor/shot line. How does that work in 2 or more knots of current? That's bloody uncomfortable for divers. I guess in locations with little or no current then a fixed line is possible. Certainly not a general rule around the world -- nor around the US -- as currents vary massively.
Yes.. tied in.

You can drift off a wreck here and there are protocols in place for how to do so safely, but it's also slightly frowned upon and much better to run a reel and get back to the anchor line.

You always need to have a contingency plan. Despite your best intentions you might have to start ascending away from the anchor line, or get blown off it at some point. So, what do you intend to do in that situation? You guys need to think these things through and not put yourself into situations where a single mistake or failure could cause serious dangers.

It's the same here. You can shoot an smb (they prefer lift bag for non emergency vs smb for emergency). It's just not the preferred way. I agree though, there's no reason to be diving if you can't shoot a bag.
There are many fishing boats around here as well. If we see fishing operations over our intended dive site then we either wait until they leave or shift to an alternate site. During the dive, the dive boat should be flying an Alpha flag (limited maneuverability) and as I understand the rules of the road that gives priority over fishing boats. If necessary the dive boat crew can warn off fishing vessels via VHF radio or loudhailer (or even physically moving to block another boat as was necessary in one case). This is what I meant by making the dive boat captain part of an integrated team; for tech diving they can't be just a taxi driver.
We would switch to another site. Again I really think it boils down to fisherman working and divers playing... 1st come 1st serve though.
 
I'm trying to figure out what I can attach to the anchor line that will serve as a visual reference while switching gases, etc. I'm imagining some kind of giant clothespin, but haven't seen any products that seem like they would work. Anyone have any suggestions?
Most anchor lines are of braided construction and many have a red/colored tracer fiber in them too. The line itself give you plenty of visual cues if you are moderately close to it and paying attention. No need to add colored clothes pins etc. If it's a fixed mooring the boat tied into that has even more visual cues from the inevitable marine growth.

I would practice more in controlled situations before accumulating an actual open water deco obligation. There's always the chance you'll not be able to come up the anchor/mooring line. If you're already anxious about open water ascents with an anchor/mooring line reference imagine having that taken away and you'll be really stressed.

Using an SMB tied off to the bottom at a benign site is a good way to practice. The thin #24 line gives you few visual cues, basically just the tiny knot every 10ft. If you can nail practice ascents with a tiny fixed line then graduate to retrieving the SMB as you go. Eventually you'll be at the point where a fat anchor line in your face feels like cheating - that's when you're confident enough to be doing open water deco and its fun (or fun enough) to not be a stress.
 
The original question from @Smache was about using an anchor line. As usual, the thread has drifted :)
I guess anchor yourself to the original wuestio unless you feel it is unsafe to do so, or if the drift reach 2 knots, if that happens launch whatever argument to anchor your position and hang onto it?
 
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