Lessons Wreck Penetration

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Akimbo

Just a diver
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There are a lot of posts on Scubaboard about finding your way out of a wreck and avoiding stirring up silt, but not much on other factors that influence when it is safe to penetrate a compartment. I thought I would share this experience:

I was in Navy First Class Diving School in the early 1970s. Among other things, this training was the transition from a working air diver to diving supervisor. A Master Diver came in periodically to lecture. I can't remember his name or if this was during class or a BS session after. Anyway, he describes this scenario:
"A hull breach in the engine room is suspected, some catwalks are known to have failed along with one of the generator mounts. She lists to port about 40° and the machine shop is on the starboard side along with spares stores. Any of you guys have any problem suiting-up for this survey?"

Young and cocky hairy-chested deep sea divers that we were, we all said "I'm in". Then he says:
"OK, now would you send your brother in there who is expecting his first child?"

Stunned silence. Then he says:
"No? Then what the hell are you going in there for?"

Man did we fall into that one. A lifetime lesson was learned that day. We took much better notes on preparing spaces to work in after that.
 
I am perplexed after reading wreck diver training outlines and talking to a couple of instructors. IMHO, treatment of silt-outs is incomplete and backwards. I am a firm believer that divers need to spend a fair amount of time in zero visibility before they penetrate a wreck or even start a wreck diving class.

Here's the logic:
Wreck divers will eventually find themselves in black-out conditions. It really doesn't matter why. All your lights can fail. Silt can be stirred up by an awkward move, another diver, shifting debris, or wresting a prize binnacle to sunlight. In the end you are in the dark and have to deal with it.

Everyone's first experience in black water is uncomfortable at best. Symptoms range from a little paranoia to "get me the hell out of here" panic. Air consumption goes up, time perception is shot, and you reflexively recoil from the slightest touch — making matters worse. Almost everyone gets over it in time.

IMHO, the great majority of wreck diving classes compound the problem. They place great emphasize on avoiding black-out conditions and address managing it with lip service. All the talk about avoidance, spare lights, and depending on your buddy isn't very useful when you are suddenly alone and in the dark. That dread and total lack of habituation is a recipe for disaster.

How are you going to monitor your air supply if you can't see? How are you going to find your buddy — who might be in full panic mode? How are you going to get out if you can't think straight? Becoming comfortable in these conditions far in advance of being faced with them can turn a deadly situation into an inconvenience.

OK, so how do I learn?
You don't need an instructor for this. You have no idea how long it will take; it is almost entirely mental preparation. You need to feel alone. Have a buddy on the surface watching your bubbles if you feel it necessary. You don't need to be in more than 5-8' (1500-2400mm) of water.

Find some shallow ink-black water in a safe location to practice in. Try to perceive as much as possible from your other senses — but wear gloves. It is best to find a mud bottom and stir it up if necessary. If that is too difficult, start by blacking out your mask with tape or turning your light off on night dives, but remember that is isn't quite the same. I have no idea why. Make sure you graduate to black water during the day. You will be amazed what you can learn in water shallow enough to stand up in.

I was lucky. One of my six days of ocean dives in Scuba school was devoted to black water. The instructor would tie a large nut onto a ping pong ball with about 3' (1 M) of string. Then he distributed about 30 of them in really shallow water with a mud bottom and zippo vis. Competition between students to recover the most ping pong balls earned them two air fills and coveted bragging rights. The desire to win and not look like a wimp probably helped this all-male class. I didn't appreciate it at the time, but those dives made my first night dive really easy along with US Navy Diving School years later.

When is it enough?
You will know. Air consumption will be at or near normal, you won't flinch every time something touches you, and you can start to "see" with your hands. Then you are ready to start your wreck class.
 
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I am perplexed after reading wreck diver training outlines and talking to a couple of instructors. IMHO, treatment of silt-outs is incomplete and backwards. I am a firm believer that divers need to spend a fair amount of time in zero visibility before they penetrate a wreck or even start a wreck diving class.

Here’s the logic:
Wreck divers will eventually find themselves in black-out conditions. It really doesn’t matter why. All your lights can fail. Silt can be stirred up by an awkward move, another diver, shifting debris, or wresting a prize binnacle to sunlight. In the end you are in the dark and have to deal with it.

Everyone’s first experience in black water is uncomfortable at best. Symptoms range from a little paranoia to “get me the hell out of here” panic. Air consumption goes up, time perception is shot, and you reflexively recoil from the slightest touch — making matters worse. Almost everyone gets over it in time.

IMHO, the great majority of wreck diving classes compound the problem. They place great emphasize on avoiding black-out conditions and address managing it with lip service. All the talk about avoidance, spare lights, and depending on your buddy isn’t very useful when you are suddenly alone and in the dark. That dread and total lack of habituation is a recipe for disaster.

How are you going to monitor your air supply if you can’t see? How are you going to find your buddy… who might be in full panic mode? How are you going to get out if you can’t think straight? Becoming comfortable in these conditions far in advance of being faced with them can turn a deadly situation into an inconvenience.

OK, so how do I learn?
You don’t need an instructor for this. You have no idea how long it will take; it is almost entirely mental preparation. You need to feel alone. Have a buddy on the surface watching your bubbles if you feel it necessary. You don’t need to be in more than 5-8' (1500-2400mm) of water.

Find some shallow ink-black water in a safe location to practice in. Try to perceive as much as possible from your other senses… but wear gloves. It is best to find a mud bottom and stir it up if necessary. If that is too difficult, start by blacking out your mask with tape or turning your light off on night dives, but remember that is isn’t quite the same. I have no idea why. Make sure you graduate to black water during the day. You will be amazed what you can learn in water shallow enough to stand up in.

I was lucky. One of my six days of ocean dives in Scuba school was devoted to black water. The instructor would tie a large nut onto a ping pong ball with about 3' (1 M) of string. Then he distributed about 30 of them in really shallow water with a mud bottom and zippo vis. Competition between students to recover the most ping pong balls earned them two air fills and coveted bragging rights. The desire to win and not look like a wimp probably helped this all-male class. I didn’t appreciate it at the time, but those dives made my first night dive really easy along with US Navy Diving School years later.

When is it enough?
You will know. Air consumption will be at or near normal, you won’t flinch every time something touches you, and you can start to “see” with your hands. Then you are ready to start your wreck class.


I like the last part. I spent hundreds of hours picking up golf balls. A decent portion of the time this was accomplished in touch mode (Zero Vis). You eventually learn a very specific hand sweeping motion that is both quick, yet gentle. Your spinal cord (I guess) learns the feel of your palm sweeping over the very edge of a ball buried beneath the mud, and you learn to grab the ball with an instant snatch that is way too quick to be done consciously. Your hand grasps the ball before you even consciously sense it.

The other really weird thing was when your hand would sweep under a ball sitting on a hard sandy bottom. The ball would be knocked forward and upward into the water column by the unintended impact with the hand. This would impart a backspin on the ball.

You would stop the sweeping motion, rotate your hand into the palm up position and would catch it your open palm, often with your eyes closed. Even though you could not see anything, you would feel the contact, learn the shape of the turbulent flow that your hand created and judge exactly where the ball would fall (as it spins). . My success rate for this was probably 60 or 70%. I have no idea how I was doing it.. I guess you learn by doing it thousands of times in water clear enough that you can see your hands and the balls trajectory and eventually, you didn't need to see.
 
I like the last part. I spent hundreds of hours picking up golf balls. A decent portion of the time this was accomplished in touch mode (Zero Vis)…

I can't remember where I first heard the phrase but I have always liked "diving by braille".
 
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Heard it from some PSD diver, perhaps?

No, it predates Public Safety Divers by decades. Could have been in the Navy in the early 70s but I think it was before that. I'm thinking Moss Landing Marine Lab but can't swear to it. A friend was a biologists there and was big on collecting critters that live in the mud.
 
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You can do all of this preparation work in total "blackout" where you can't even see the light coming out of your own dive light when diving in certain parts of the Long Island Sound in NY on a DAY dive!!! I used to take my Master Diver and leadership students to dive some of these spots during their training. We called it "Braille Diving" :)
 
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Love this, next time I re-up my SAR/R-I I'll be ready with the history of that term.

I know that I'm a trained and practiced ocean mudpuppy, most happy with that too. Now working on trim and buoyancy. Need new skillz... Coming at it from a distant planet. I'll get there.
 
Just dive behind most southern california open water classes if you want to practice in zero viz :-)

I know you are being a little facetious unless maybe the dive class is off the Marine Room or in Scripps Canyon. There are places in Mission and southern San Diego Bays that are pretty good… err bad. ;)

It is really interesting how black water effects people differently even compared to 1-2' of visibility in a localized area. You know you are in ink-black water when you put a dive light flat against you mask and can barely see a dull glow. Night dives really don't work all that well, probably because of bioluminescence and knowing you can turn your light back on. Even pulling your mask off in normal visibility isn't the same, but is also a good thing to conquer.

In any case, don't add a hard overhead to the equation until you are completely comfortable in black water and learn how to get out blind.
 
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