DIR- GUE Why are non-GUE divers so interested in what GUE does?

[beester]

It's not a real dive, no one is going to go down a rope to 75m and simply stay there for 45 minutes. Dives have goals and are planned as such by groups of divers. With known wrecks or sites, information is gathered from others as to the site conditions or wreck layout and when is the best time to make a dive in order to hit the wreck when vis and bottom conditions are most favorable. The group can then decide what they wish to see or do and estimate how much time may be needed to complete the dive. For unknown wrecks or sites all that goes out the window and even with good surface sonar it could need a number of survey dives to get a feel for the wreck layout. Hypothetical dive times and depths are a pointless exercise unless just for fun with dive software. So putting a diver on the spot on a forum by asking how they would carry out a dive with just depth and time to go on is silly.

THIS!! Very true! I always crinch when someone wants to know the full dive/deco details or asks give me an example of a dive with x bottom time and x deco, so they can masturbate over the minute details of the theoretical dive.

Also very true about unknown sites. To be honest there are not a lot of divers that I know who are willing to put time and money aside for a weekend or longer, hop on a boat and check out what could easily also be a heap of rubble. But that's what the true adventure is. With rebreathers it becomes a bit easier because if the potential wreck is really nothing, at least you didn't waste expensive gas.

 

[beester]

Oh sure a 2nd rebreather does add A LOT of complexity and takes a lot of training, far more than with OC bailout. When I look at this picture posted earlier:
View attachment 737773
I'd rather have a backup rebreather. And if you don't know if your backup rebreather works, you are doing something really wrong.

I will be doing some expeditions in the future where it has some huge advantages for bailout. But baby steps. First need to master CCR with air dil! I'm going super conservative on my progression there.

So far within GUE context I don't know who is using a backup rebreather. It might be used in WKPP long range dives but I simply don't know. I think I know most EU side instructors and they don't use them, even for very significant dives they use OC bailout.

 

[wetb4igetinthewater]

For unknown wrecks or sites all that goes out the window and even with good surface sonar it could need a number of survey dives to get a feel for the wreck layout.

Side scanning sonar is the primary tool in the Aegean for evaluating/finding a wreck. The resolution isn't great, but one can get some fairly good information from SSS, as seen on the Fiskardo shipwreck: "Fiscardo wreck" in Kefalonia: The largest Roman shipwreck in the eastern Mediterranean

(Fun fact: One of the professors of Dr. Ferentinos, one of the professors on the marine geology expedition that accidentally discovered that Roman merchant shipwreck, is Dr. Vamvakas, who did the research for his first PhD aboard the Calpyso).

SSS is the tool that I will be using to try to find a "graveyard of shipwrecks" that the oldest surviving sponge diver told me about. Unfortunately, he has terminal cancer, so there is no possibility of taking him out on the water to further pinpoint the location. We sure as heck won't be doing it by diving on rebreathers.

Photogammetry, the current primary tool for surveying by marine archaeologists, is going to be displaced by cost/logistics effective close up 3D laser scanning. Regardless of whether the efficiency of the scanning is improved by autonomous robotics, divers are still needed in the near term for site preparation in order to maximize the data obtained from a wreck site.

So far within GUE context I don't know who is using a backup rebreather. It might be used in WKPP long range dives but I simply don't know. I think I know most EU side instructors and they don't use them, even for very significant dives they use OC bailout.

They are going to start. I know one diver in Greece that does this, possibly a second. The capabilities of the cost effective ROV/laser scanner both have maximum depths of 300 meters. Now obviously no one is going to expect divers to set up vacuum hoses at those kind of depths on rebreathers. That takes an exoskeleton suit or a different (much more expensive) ROV.

I don't know the practical limits for working at depth on a rebreather. I will tell you that at 60 meters and below to that limit, there's a real load of shipwrecks waiting to be scanned and possibly excavated. Given that with this just released laser scanner, you could easily scan a shipwreck in under 5 days, you could be going from wreck to wreck to wreck to wreck that are all at different depths. A backup rebreather is logistically far simpler and takes up far less deck space than all the cylinders required.

 

[Celt]

Side scanning sonar is the primary tool in the Aegean for evaluating/finding a wreck. The resolution isn't great, but one can get some fairly good information from SSS, as seen on the Fiskardo shipwreck: "Fiscardo wreck" in Kefalonia: The largest Roman shipwreck in the eastern Mediterranean

(Fun fact: One of the professors of Dr. Ferentinos, one of the professors on the marine geology expedition that accidentally discovered that Roman merchant shipwreck, is Dr. Vamvakas, who did the research for his first PhD aboard the Calpyso).

SSS is the tool that I will be using to try to find a "graveyard of shipwrecks" that the oldest surviving sponge diver told me about. Unfortunately, he has terminal cancer, so there is no possibility of taking him out on the water to further pinpoint the location. We sure as heck won't be doing it by diving on rebreathers.

Photogammetry, the current primary tool for surveying by marine archaeologists, is going to be displaced by cost/logistics effective close up 3D laser scanning. Regardless of whether the efficiency of the scanning is improved by autonomous robotics, divers are still needed in the near term for site preparation in order to maximize the data obtained from a wreck site.


They are going to start. I know one diver in Greece that does this, possibly a second. The capabilities of the cost effective ROV/laser scanner both have maximum depths of 300 meters. Now obviously no one is going to expect divers to set up vacuum hoses at those kind of depths on rebreathers. That takes an exoskeleton suit or a different (much more expensive) ROV.

I don't know the practical limits for working at depth on a rebreather. I will tell you that at 60 meters and below to that limit, there's a real load of shipwrecks waiting to be scanned and possibly excavated. Given that with this just released laser scanner, you could easily scan a shipwreck in under 5 days, you could be going from wreck to wreck to wreck to wreck that are all at different depths. A backup rebreather is logistically far simpler and takes up far less deck space than all the cylinders required.

They are mouth watering images, all the best with your search and work. Not casting any doubt on the sponge diver but the human memory is a bit suspect when it comes to finding wrecks. A friend who was the bell man with Beasley,s was 100% sure he could remember the location of a wreck with land marks so we convinced him to join us on a magnetometer search. After a week searching and lots of diving on anomalies we gave up. But years later the wreck was found 9 miles further out to sea.

 

[PfcAJ]

So far within GUE context I don't know who is using a backup rebreather. It might be used in WKPP long range dives but I simply don't know. I think I know most EU side instructors and they don't use them, even for very significant dives they use OC bailout.

No.

Sometimes a stage rebreather on stupid long stuff, and sometimes a deco breather on stupid long stuff. But there’s always Oc bailout layin around.

 

[wetb4igetinthewater]

They are mouth watering images, all the best with your search and work. Not casting any doubt on the sponge diver but the human memory is a bit suspect when it comes to finding wrecks. A friend who was the bell man with Beasley,s was 100% sure he could remember the location of a wreck with land marks so we convinced him to join us on a magnetometer search. After a week searching and lots of diving on anomalies we gave up. But years later the wreck was found 9 miles further out to sea.

When I met him, his memory was razor sharp. I can't say why however. I can say that when he was a guide in the 2015 Fourni expedition, he dropped the divers right on top of the shipwrecks he had discovered. It is a little easier in Greece as most sponge divers didn't go beyond 70 meters, and could only see another 30 meters or so, so that limits the search areas. It doesn't take long to circumnavigate an island while towing a fish.

Now SSS is the way to confirm the reports given by sponge divers. That's another project(s) in the future. The next one I hope to be with Dr. Vamvakas and Dr. Ferentinos on the Fiskardo wreck, simply because time is not on the side of these men. If you like those images, what you will get from the latest in LiDAR will blow your mind.

 

[ginti]

They are going to start. I know one diver in Greece that does this, possibly a second. The capabilities of the cost effective ROV/laser scanner both have maximum depths of 300 meters. Now obviously no one is going to expect divers to set up vacuum hoses at those kind of depths on rebreathers. That takes an exoskeleton suit or a different (much more expensive) ROV.

I don't know the practical limits for working at depth on a rebreather. I will tell you that at 60 meters and below to that limit, there's a real load of shipwrecks waiting to be scanned and possibly excavated. Given that with this just released laser scanner, you could easily scan a shipwreck in under 5 days, you could be going from wreck to wreck to wreck to wreck that are all at different depths. A backup rebreather is logistically far simpler and takes up far less deck space than all the cylinders required.

The problems of GUE senior people with backup rebreathers is about safety. They say that, when you move to your back up gas, you want to have something bulletproof in terms of reliability, and extremely easy to use. Rebreathers are both less reliable and less easy than OC system. This is a sufficient reason for them to stick to OC backup.

Now, I don't dive rebreathers so I am just repeating what I heard. I have no idea if this approach makes sense or not.

 

[Celt]

When I met him, his memory was razor sharp. I can't say why however. I can say that when he was a guide in the 2015 Fourni expedition, he dropped the divers right on top of the shipwrecks he had discovered. It is a little easier in Greece as most sponge divers didn't go beyond 70 meters, and could only see another 30 meters or so, so that limits the search areas. It doesn't take long to circumnavigate an island while towing a fish.

Now SSS is the way to confirm the reports given by sponge divers. That's another project(s) in the future. The next one I hope to be with Dr. Vamvakas and Dr. Ferentinos on the Fiskardo wreck, simply because time is not on the side of these men. If you like those images, what you will get from the latest in LiDAR will blow your mind.

Do you have a good relationship with archaeologists, are you able to get on with them. I've always found there's a bit of a clash between divers and archaeologists but that could be office armchair archaeologists, the people working on site could be totally different. I know nothing about the GUE system but it does seem to suit organised underwater work such as the preservation of underwater sites. My experience of archaeologists is there quite happy to let divers do all the heavy lifting and work but then like to take over and call the shots.

 

[wetb4igetinthewater]

The problems of GUE senior people with backup rebreathers is about safety. They say that, when you move to your back up gas, you want to have something bulletproof in terms of reliability, and extremely easy to use. Rebreathers are both less reliable and less easy than OC system. This is a sufficient reason for them to stick to OC backup.

Now, I don't dive rebreathers so I am just repeating what I heard. I have no idea if this approach makes sense or not.

I can understand that. I think that will ultimately change, but it will take a while. If not, they'll miss out on a lot of projects.

Do you have a good relationship with archaeologists, are you able to get on with them. I've always found there's a bit of a clash between divers and archaeologists but that could be office armchair archaeologists, the people working on site could be totally different. I know nothing about the GUE system but it does seem to suit organised underwater work such as the preservation of underwater sites. My experience of archaeologists is there quite happy to let divers do all the heavy lifting and work but then like to take over and call the shots.

Yes, but I'm not a GUE person. I'm working through a completely different network. But the government/archaeologists call the shots. It is a coordinated effort. There's site preparation (as two of our targets are wood which decays rather quickly in the Aegean), then the laser scanning, and then the restoration of the protecting material. We have allocated 5 days per shipwreck, though the ancient wrecks don't need protected material to be placed. Weather is the primary concern.

It is our hope, and the expressed hope of the archaeologists in this first project, that we work together for many projects.

 

[ls23]

I can understand that. I think that will ultimately change, but it will take a while. If not, they'll miss out on a lot of projects.

On ocean projects I don't think the OC bailout is the limiting factor, but rather the weather and unpredictable conditions on the surface.