Diving

[secondcurve]

This is a little off topic, but I just read a great dive book called Shadow Divers. It is about wreck divers working off the coast of New Jersey in the early ninetees trying to locate and then identify an old German U2 boat. The thing that got me thinking about Winnipesaukee is that thet were working in 200 to 230 foot waters, about the same depth as Winnipesaukee's deepest point. It was noted that these depths are considered extremely dangerous, especially when using pure oxygen. Have any of the divers on the forum read the book?

[Mee-n-Mac]

There was a PBS show on the same sub & dive(s). IIRC there were 2 deaths, father & son, on one of the dives. They did eventually ID the sub which had been thought to have been lost in another area. As far as deep dives go there was another show I saw recently where the divers were recovering gold from a WWII transport ship. They were working saturation dives in what I thought was deeper than an unprotected (not in a hardsuit) diver could go. I think they said 600' ?!??!?? Perhaps the divers here could comment on either/both ...

[Senter Cove Guy]

I read the book in Oct. 2004 and bought the DVD of the PBS show in 2005. Both are excellent. Three people lost their lives while diving the sub (U-869) and John Chatterton, who retrieved the evidence that ultimately identified the sub, almost lost his after executing a special maneuver to get himself deeper into the sub and getting temporarily pinned under some wreckage that fell on him.

I had a chance to talk with John Chatterton at the 2005 Boston Sea Rovers conference in March 2005. He, Richie Kohler (another U-869 diver) and Robert Kurson (the author of Shadow Divers), made a presentation at the conference.

The DVD has a lot of great underwater footage plus some graphical animations of the special maneuvers that Chatterton had to perform to get deep enough into the sub to get the evidence. It also contains a lot of WWII information about German submarine warfare planning and a visit by Richie and John to a former U-869 submariner still living in Germany and to a relative, living in the United States, of one of the submariner's who died when the sub went down.

Chatterton, Kohler and other U-869 divers used a trimix gas (oxygen, helium and nitrogen) when diving the sub. The helium took the place of some of the nitrogen that normally would have been in the mix which has the effect of reducing the absorption of Nitrogen into the blood thus reducing the chances of getting the bends. They might have breathed pure oxygen during their ascent from 235 feet while stopping at pre-determined decompression depth stops to allow Nitrogen to purge from their bloodstream. A 20-25 minute bottom time dive at 235 feet requires somewhere in the 1.5 - 2 hrs of decompression stops I believe.

[Mink Islander]

once they get to a safe depth where the partial pressure of oxygen based on whatever EAN mix they're using is 1.6 bar or less, right?

[AttitudeAdjuster]

Originally Posted by Mink Islander

once they get to a safe depth where the partial pressure of oxygen based on whatever EAN mix they're using is 1.6 bar or less, right?

I believe you mean 1.6Po2. 100% oxygen has a Po2 of 1.6 @19.8 fsw.
they would not want to ascend from 235 on 100% that would be a deadly case of oxtox.

[Senter Cove Guy]

Originally Posted by AttitudeAdjuster

I believe you mean 1.6Po2. 100% oxygen has a Po2 of 1.6 @19.8 fsw.
they would not want to ascend from 235 on 100% that would be a deadly case of oxtox.

I did not mean to infer that they would have been breathing 100% oxygen all the way up from 235 feet but that at some point in their decompression, they might do that to hasten the purge of nitrogen.

The DVD clearly shows that each diver began his dive with 4 tanks. Two in the standard position on their back and one on each side hanging from their buoyancy compensator.

The father and son team that died made deadly errors. Firstly, they couldn't afford to buy trimix so they dove using air. Secondly, the son got trapped inside the sub while the father was outside. He finally went in looking for his son, found and freed him but both exited the sub from a different point from where they went in and where they'd left their extra tanks. Nitrogen narcosis set in because they were breathing air vs. trimix and in a stressful situation and they couldn't find their extra tanks. Almost out of air, they surfaced without decompressing and both died of the bends.

[Mee-n-Mac]

I'm curious if the divers could settle an old question I have. Somewhere I recall reading or seeing some info that while decompression stops usually prevent the bends from occuring, it's not guaranteed. You can do everything "by the book" and still end up with bubbles where you don't want them ? Just curious ....

[gtxrider]

Can the experts help on this question? Can you get the bends coming up to fast in shallow water? We were told that by our diving instructor.

It also depends on the number of dives over a given time period.
Did you ever notice that I you when hear a diver speaking on those very deep dives their voices sound funny? The helium in the mix does that.

[warren]

its a great story,the owner of the dive shop in concord nh. rob dove the u-boat this summer and said it was a wonderfull dive. he said the vis was not very good until he hit about 150 feet and then the the whole sub came into view underneath him. cool huh, warren

[Senter Cove Guy]

Originally Posted by gtxrider

Can the experts help on this question? Can you get the bends coming up to fast in shallow water? We were told that by our diving instructor.

Unlikely because the bends is related to the amount of nitrogen in the bloodstream. Diving depth and the related pressure that exists determines how much nitrogen is absorbed by the blood. So it's more a factor of how deep you dive and how long you are there that controls how much nitrogen is in your bloodstream.

However, the general rule is don't ascend any faster than 30 feet per minute and either obey your dive computer when it says STOP at calculated decompression stops or, if not using a computer, plan your dive and dive your plan.

One thing you don't want to do in any depth of water, when breathing compressed air, is hold your breath when ascending. A depth change of only 4 feet is enough to cause the compressed air in your lungs to expand and burst them which would be deadly.

[Senter Cove Guy]

If you liked reading Shadow Divers, then you might also like the following 2 books:

Deep Descent - A story about diving the Andrea Doria

Last Dive - The complete story of the lives of the father & son team that died diving the U-869.

[Mee-n-Mac]

Just to answer my own question as to how deep unprotected people could go ... I found that a few years ago somebody went to 1010 ft. Don't know the details but I guess the 600 ft I was wondering about (above) is indeed possible. Personally I think I'll leave the deeper than snorkel depths to an ROV.

[Grant]

Oddly enough, we routinely hear about people taking DCS hits after what most would consider relatively shallow, short dives. In fact, I believe the author of "The Last Dive" took a pretty nasty hit after a rather basic dive. Took him out of commission for quite some time. So, yes, you can follow the tables, use a super-conservative dive computer, hydrate like a fish, take prolonged safety stops, use Nitrox, tri-mix, stay shallow, ascend slower than the slowest bubble, wear a rabbit's foot, pray, and still get hit.

Today, in addition to the customary 3-5 minutes @ 15 ft. "safety stop," a lot of recreational divers are factoring in a short stop at a depth equal to 1/2 of their deepest point of the dive. Statistics suggest that this does indeed lessen the frequency of DCS. There are so many factors.

Richie Kohler, one of the two primaries in "Shadow Divers" lives a few miles from where I'm sitting right now. The Jersey dive community is very active around here, and all the local shops have affiliations with the boats up and down the shore. The Rouses, the father-son team that died diving the "U-Who," dove out of my local shop, and the younger Rouse worked there. Some of their artifacts from the Andrea Doria are on display in the shop.

[Grant]

Originally Posted by Mee-n-Mac

Just to answer my own question as to how deep unprotected people could go ... I found that a few years ago somebody went to 1010 ft. Don't know the details but I guess the 600 ft I was wondering about (above) is indeed possible. Personally I think I'll leave the deeper than snorkel depths to an ROV.

The open circuit record is 1030 feet -- and that was a bounce dive. FWIW, "recreational" diving is considered to be anything to 130 ft, with anything deeper considered "deep diving." (Your mileage may vary.) Most basic certs (OW) set a limit at 60 ft. (unenforced, of course). Winnipesaukee is pretty worthless (extremely dark, murky, cold) below, say, 50-60 feet, and the 'best' diving in the Lake is probably in the 30-50 foot range.

The 600 you mentioned is indeed possible, and done fairly often, but that is a seriously deep technical dive, requiring special gases, prolonged decompression, and LOTS of training.

[secondcurve]

Grant & Senter Cove Guy:

Thanks for the info on diving. Have either of you had problems or close calls when diving? I know that you proably haven't gone as deep as the divers in Shadow Divers but none the less, it seems risky even in waters as tame as Lake Winnipesaukee. How deep have each of you gone down? How many dives have you each made. Finally, isn't diving in Winnipesaukee kind of boring? Thanks for any input. Senter Cove Guy, I think I'm going to take your recoomendation and pick up a copy of the Last Dive.

Thanks

[Grant]

Funny you should ask...

Actually, Senter Cove Guy and I live quite close to each other at the Lake, and dive together fairly often...when crappy weather and lack of air don't conspire against us...

As far as depth, I've only gone as deep as 120', but not in Winnipesaukee. As I mentioned above, most of the good diving in Winni is much shallower than that. My max to date in the Lake is probably '70 or so.

As for Winnipesaukee, it's FAR from boring. Lots of stuff to see. It's 70 square miles of puddle carved out by a glacier -- so the geologic formations alone are worth the price of admission. And the junk...don't get me started on the junk...and I'm but a newbie in this department. Page a forum member knows as Winnipesaukee Divers...he's a bona fide junkmeister general and a seriously seasoned diver. He's found all sorts of glorious refuse.

I'm just in it for the fun and to see another side of the Lake I've loved all my life. If I find some treasures and see some critters along the way, bonus. If you're interested in hitting some of the cooler spots in the Lake, jump on one of the charters with Dive Winnipesaukee out of Wolfeboro. There aren't too many dive shops on the planet with a boat parked right out back! Wonderful folks who are more than glad to show you the popular sites around the Lake.

Funny, at least two or three times a year, I have people approach me on the street in Wolfeboro, as I'm taking a cylinder to the shop, who ask me, "You actually dive in this lake? What on earth is there to see in there???" Kills me every time.

Senter Cover Guy (left) and yours fatly, er, I mean truly, on the surface this fall about 7 hours south of Winni...

[SIKSUKR]

How come Grant and SCG are diving behind a Super Wal-mart in their water treatment pond?Just kidding guys!!

[Grant]

Because they needed underwater "greeters," and because WalMart pays so well.

[secondcurve]

Grant:

Thanks for the comments and the pictures. I'm surprised that there is so much to see in the lake. I'll have to consider giving it a shot this summer. I am surmising that you haven't had any close calls from your lack of response to this part of my question which is good. I always have been a little leary of diving thinking it is too dangerous. Maybe Its time to take a chance. By the way, the day after tomorrow the days begin getting longer! Spring and warm weather can't be far behind!

[Senter Cove Guy]

Even though I've been certified for almost 25 yrs, it's only been the past 3 yrs that I've taken up diving seriously. I'm a cautious diver and try to do most everything by the book. I have never had a decompression problem but did have a few moments of anxiety last summer while on a dive with Grant. We were diving at Diamond Island looking for the "Empty Pockets" wreck. We were in the 55-60 foot depth range and my mask had fogged a bit. I decided to lift my mask from my face to let some water in to clean it and then purge the water by blowing air from my nose. A procedure that I've used many times before. However, this time, my hood was lower than usual on my forehead and when I tried to reseat my mask on my face it was overlapping on the hood and I couldn't clear it. There I was at 60 feet and everything is blurry. STOP, BREATHE, THINK, ACT. After a few seconds all I really had to do was push my hood back a bit, reseat my mask and clear. Ahhhhh, I can see again, but where is Grant? Well...he wasn't very far away and we finished the dive. Alas...we were unsuccessful in finding "Empty Pockets" even though we've both seen it before.

I did the St. Lawrence River wreck diving trip with Dive Winnipesaukee last summer. It was fantastic. In mid-July the river was 72 degrees from top to bottom. The deepest most of us went on the trip was 110 feet. Like Grant, the deepest I've been in Winnipesaukee is about 70 feet. There is a known wreck at about 85 feet off of Ship Island that I'd like to try and find next summer.

I've done approximately 75 dives total:
65 in Winnipesaukee
4 in Dutch Springs Quarry (Bethlehem, PA)
4 in the Caribbean (Grand Cayman & Cozumel)
1 in Long Island Sound
1 in Brownstone Exploration & Discovery Park (A quarry in Portland, CT.)

I'm looking forward to possibly doing some diving in the Mediterranean Sea next summer and to going on the St. Lawrence trip again as well.

But, I will confess, I'd really like to newly discover something else in Winnipesaukee.

[Misty Blue]

Grant and SCG:

I'm gett'en a see doo scooter for Christmas!

There is a 20# box with my name on it under the tree and I peeked. I guess that makes me naughty!

Wanna play next summer?

Misty Blue.

[Winnipesaukee Divers]

Originally Posted by Misty Blue

Grant and SCG:

I'm gett'en a see doo scooter for Christmas!

There is a 20# box with my name on it under the tree and I peeked. I guess that makes me naughty!

Wanna play next summer?

Misty Blue.

I have one of those and 2 Tyger sharks; they're a lot of fun. The battery’s last longer than my air and they pull me along at 2mph (any faster and the water rips your mask off). We use the See Doo to blow silt away while I'm working on moorings (works real good).

Comparing notes with the other divers here:
Over 4000 lifetime dives
Deepest dive 240 ft.
Deepest lake dive 137 ft. (won't be going there again)
Worst diving situation... Wow, there isn't enough time to go into that here but that old saying "That, which dose not kill you, makes you stronger" keeps coming to mind.

[Grant]

Originally Posted by Senter Cove Guy

Ahhhhh, I can see again, but where is Grant? Well...he wasn't very far away and we finished the dive. Alas...we were unsuccessful in finding "Empty Pockets" even though we've both seen it before.

I swear someone moved the wreck. A few weeks before, there was a nice, convenient Chlorox bottled on a rope tethered to the wreck. Two weeks later, we couldn't find it. But we did see some other interesting junk on that one. Funny thing is that we found that boat no problem diving from shore about three years ago. But in August '05, we just went back and forth and back and forth at 54 feet...no boat. Maybe the eels snatched it.

Originally Posted by Senter Cove Guy

I did the St. Lawrence River wreck diving trip with Dive Winnipesaukee last summer. It was fantastic. In mid-July the river was 72 degrees from top to bottom. The deepest most of us went on the trip was 110 feet.

I'm soooooooooooooo going on that trip this year.

Originally Posted by Senter Cove Guy

Like Grant, the deepest I've been in Winnipesaukee is about 70 feet. There is a known wreck at about 85 feet off of Ship Island that I'd like to try and find next summer.

And, hopefully, the line that leads down there will still be tied. It was loose this summer, and I re-tied to a rock. But there are a lot of people trolling around there (I found a full downrigger and ball wedged in the rocks at about 50' in July or August), and it would be easy to break. It's not very thick. There's a series of Chlorox bottles (bonus points for two Chlorox bottle references in one post?) that lead down to that wreck from the end of the line from about 50 feet. Let's go!

Originally Posted by Senter Cove Guy

But, I will confess, I'd really like to newly discover something else in Winnipesaukee.

Sign me up. You have my number.

[donnamatrix]

I loved Shadow Divers, both the book and the the television special. Another excellent book, published back in 1996 or 1997 is called Ship of Gold in the Deep Blue Sea. It's the true story of the sinking of the Central America side wheeler. In 1857, the Central America, a sidewheel steamer ferrying passengers fresh from the gold rush of California to New York and laden with 21 tons of California gold, encountered a severe storm off the Carolina coast and sank, carrying more than 400 passengers and all her cargo down with her. She then sat for 132 years, 200 miles offshore and almost two miles below the ocean's surface--a depth at which she was assumed to be unrecoverable--until 1989, when a deep-water research vessel sailed into the harbor at Norfolk, Virginia, fat with salvaged gold coins and bullion estimated to be worth one billion dollars. Herndon, Virginia is named after the captain of the Central America. Excellent reading.

I am also a certified NAUI diver.

[Grant]

I'm a big advocate of NAUI training. Then again, any training depends on the instructor. But, IMHO, NAUI is the better of the big agencies. My son starts his NAUI training on Monday, so we'll have another Winni Diver on board this summer.

[ApS]

I was surprised to read that divers are subject to "tunnel vision" as a result of panic—and the flow of adrenaline.

Anyone here experienced it—and can describe it?

[Winnipesaukee Divers]

Can't say that I have ever been bothered by tunnel vision... In my world under the water it is a major sensory deprivation, I can't see much (I'm always in the muck), can't hear anything (hood on and air bubbles rushing by), can't feel anything (always wear heavy gloves and exposure suit) and I'm all consumed on getting the task at hand completed.

Well, Okay, so it not all that bad, I do have some good dives. In fact I take time on every dive to do a little exploring and you're right not much gets by me down there. I'm acutely aware of what's going on around me at all times. A good diver never puts himself in a panic situation; mistakes made down there are very costly. When a situation dose arises, the diver doses the three "R"s, React, Re-gain control and Respond.