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June 29, 2007

Diving as a means for terrorism

In this day and age where we can't even take toenail clippers and a bit of toothpaste or hair gel onto an airplane for fear of its use for acts of terrorism, I suppose almost anything can be seen as a potential threat. So why not scuba diving?

This morning I saw that washingtonpost.com and other news agencies reported that the FBI has recently alerted dive shops around the country to look out for suspicious divers seeking advanced training, including night diving, diving in murky waters and pipes, advanced navigation and use of underwater vehicles. The advisory was said not to be based on a particular threat but as a routine caution. Instructors, the Post quoted, should be aware of "odd inquiries that are inconsistent with recreational diving." With NAUI estimating that there are about 1,800 dive shops around the country there are plenty of places to learn the ins and outs of diving and get the required certifications. Terrorists could then easily rent equipment, have their tanks filled and so on.

But what harm could a scuba diver do? Peruse history and you see that divers often played an important role in warfare. Terrorist fears are thus not unfounded. In WW II, Italian and British divers successfully launched devastating underwater attacks on enemy warships.

The underwater division of the Italian Navy pioneered the use of divers and mini-submarines to attack British ships stationed in Alexandria and Gibraltar in 1941. In December of 1941, the Italian submarine Scire carried three "human torpedoes." Each of those 23-feet mini subs, also nicknamed "maiale" which is Italian for "pig," (because it was about as difficult to ride and steer like a wild pig) had two divers sitting astride them like cowbows. (The picture shown is of a 1:48 scale model available from a Polish website) The design went back to World War I where the Italians had sunk the feared Austrian battleship Viribus Unitis and a freighter with a modified torpedo that was placed under the warship. The Maiale was powered by a small electric motor and carried up to 650 pounds of explosives in a detachable warhead upfront. The idea was for the two divers to get their ride through anti-submarine measures like nets and such, find their target, dive underneath it, attached the warhead like a mine to the hull of the boat, or perhaps just place it on the bottom, arm it, and then, if possible, hightail out of town. The Italians were remarkably successful with this tactic, attacking and sinking a British tanker and two battleships in the port of Alexandria, Egypt, and sinking several more during the war. (See Wiki entry on the Decima Flottiglia MAS.)

The British captured one of the Italian minisubs and copied the design and diving gear. In 1943, 51-feet long X-craft midget subs (see Wiki entry on the X class subs.), which had both diesel and electric power, tried to sink the German warship Tirpitz moored in a heavily guarded port in northern Norway. The plan was to drop charges underneath both sides of the enemy ship and then detonate them with a time-delayed fuse. That operation was only a partial success, but the Tirpitz was damaged badly enough to be out of commission for a crucial six months.

Diving history is also full of examples of divers using rebreathers to infiltrate enemy territory or perform military operations underwater. They used closed-circuit oxygen rebreathers that issued no tell-tale bubbles at all. The depth limitation of 20 to 30 feet is rarely on obstacle for such operations, and they are still being used today.

So how does all this fit into terrorism 21st century style? Well, the obvious answer is that if nail clippers and toothpaste are viewed as enough of a danger to make them illegal on airplanes, then the use of scuba equipment can represent a significant danger indeed. Terror is psychological warfare and harassment. Massive attacks like 9/11 are few and far between, but the ever-present threat impacts our lives. So it's easy to see how a few strategically executed and highly publicized attacks using scuba technology could have a devastating impact on our sport. Let's hope we won't get singled out. Terror comes in many shapes and forms and it's always better to be safe than sorry. So the FBI advisory makes sense.

Posted by conradb212 at 11:16 PM | Comments (0)

June 22, 2007

Body fat, body composition report, and diving

Yesterday I took my 11-year-old to a doctor's appointment at the Kaiser HMO facility in South Sacramento. On the way in I noticed that the Health Education room, sort of a small library with pamphlets and instructional diagrams and such, offered free body fat tests. I thought I'd stop by if the appointment didn't take too long. It didn't.

The body fat test is done by a machine. It looked like a cross between a scale and a treadmill. You stood on it, it measured your weight, and then you entered your height, age, gender, whether you were clothed or not (who wouldn't in a public facility?), and what body type you were, the choices being athletic, normal, and sedentary. You then held on to two metal handle bars so the machine could send a low intensity electrical current through the body. The process is called bioelectronic impedance and uses the different electrical resistance of different tissues, bone, muscle and fat to determine your body composition. It takes but an instant, and then you can print out the results. So what did I get?

Well, I am six foot tall, weighed 159 pounds with clothes and gym shoes, age 56, male, and I optimistically described myself as "athletic." The body comp scale printout said I had 16.9% body fat, 83.1% fat-free mass, and 64.5% total body water. It also stated that my target weight range was 144.4 to 152.1 pounds, and that my daily caloric need was 2,331 calories, based on my "moderate activity level" -- which was defined as participating in an exercise program three days a week for 20-30 minutes. I run a fairly intense course three times a week, so I felt that counted as moderate activity.

I always thought that at about 155 pounds at 6 foot I was fairly slender, and so the printout's suggested target weight of 144 to 152 surprised me. The answer to that puzzle was that I am really a "normal" body type, and not a muscular "athletic" one. According to the body composition report, athletic types have between 6 and 13% body fat, normal body types between 14 and 19%, and sedentary ones over 20%. Had I entered "normal" in response to the body type, my target weight would probably have been just around where I am.

To be honest, I was surprised that my body fat was smack in the middle of the normal range. I thought it'd be less. So I poked around a bit to see what it all means. Here is some information I found:

NOAA has body composition standards both for males and females. At a height of 6 feet, the maximum weight for a male would be 201 pounds. Maximum body fat percentage depends on age. For men under 30 it's 23%, under 40 25%, and over 40 27%. Females are allowed 33, 35, and 37%, respectively. Scuba-doc.com states that "Total body fat of less the 22% in males, and less than 28% in females is desirable" and that "trained males however average 7-10% body fat." So I am apparently not very well trained. Dr. Jolie Bookspan's "The 36 Most Common Diving Physiology Myths" is interesting reading. Bookspan conducted post-doctoral work in saturation decompression and altitude and is certainly an expert. She praises fat as a major protection against cold and also points out that women's higher body fat percentage does not necessarily mean more body fat in pounds as women are generally shorter by several inches and weigh less. Her claim: "It's not yet known whether percentage fat or absolute fat amount is more problematic to decompression issues - if either are important - another area that is still unknown, but prone to myths." However, she points out that "Fat is a slow tissue due to gas solubility. Because of high gas solubility, fat holds much nitrogen and takes time to uptake and offgas it all. This is a property of fat and is true even for fatty areas with the same degree of blood supply as leaner tissue." Activedivers.org says that "As the percentage of body fat increases, so does the risk. Fatty tissue attracts and stores nitrogen more so than other tissue types, and inhibits the off-gas process." "Diving Science by Strauss and Aksenov states that "fat tissues have five times more affinity for nitrogen than lean tissues have."

However, by and large, there really isn't a lot of truly scientific information (readily) available about how body fat affects diving. It obviously has an impact on buoyancy. It has positive properties on heat insulation. Fatter people encounter the usual prejudices, like supposed lack of fitness or problems climbing a ladder to get on board. Wetsuits and BCs generally don't come in larger sizes. Yet, I've seen a lot of fat divers, and some very prominent and accomplished ones.

So perhaps we just don't know all that much about body fat and what it means for diving. I am surprised that according to that machine, I carry 26 pounds of body fat as I certainly can't see it. Then again, I also carry about 100 pounds of water, and that thought is downright weird.

Posted by conradb212 at 11:15 PM | Comments (0)

June 19, 2007

Underwater cameras without cases

Taking pictures underwater continues to fascinate me and I wish I had more opportunity to do so. Olympus spends a lot of money on their underwater camera gear and I made a proposal to them to do a full feature on their entire lineup, sort of an informational promo piece they could use to highlight and explain their products to customers. Sadly, the proposal was circulated back and forth but nothing ever came of it.

Anyway, having had the chance to take very different kinds of cameras on dive trips, I am now convinced that picking the right camera to take with you on a dive trip is even more important than picking the right camera on a land assignment. On land, the emergence of inexpensive, powerful, yet impossibly small and slender digital cameras means you can take excellent high-res pictures anywhere. The camera never gets in the way. For serious shooting you want a digital SLR, and those are a lot larger and bulkier and that generally means a carry case for all the accessories and so on.

All of this is multiplied underwater where we're already busy and loaded down with gear. In the beginning just remembering what to do in order to stay alive pretty much takes up all discretionary time and brain cells. Later on, as we become more comfortable in this foreign environment, bringing a camera along becomes possible and lots of fun. Yet, that means picking one that's suitable for underwater photography and then the investment not only in the camera, but also its underwater case and whatever other gear it needs. That can easily meet or exceed the cost of the camera itself even with the simple deepwater cases for point & shoot compacts. Add up the needed gear for a digital SLR, and we're talking several thousands of dollars.

Apart from the cost, a camera suitably protected for underwater duty is a lot larger and bulkier. A slender compact becomes a brick, and a SLR a rather massive contraption, especially when you add the almost always necessary external flash. So a dive really becomes a dedicated photography dive. Nothing wrong with that, but maybe there is. These days we simply expect to have a small camera along wherever we go, just in case. I almost always have one in my pocket, next to my cellphone. And soon the cameras in cellphones may be good enough that even that is no longer necessary. Never count out the greed of the telcos that make it nearly impossible to simply send a picture without signing up for expensive extra services and idiotic proprietary interfaces, but it may happen.

Anyway, point is that I'd like to take a camera with me when diving without having to worry about it. No bulk, no case, no fuss. And Olympus is blazing the trail here with the awesome Stylus 770SW, the 3.5 x 2.25 x 0.75 inch 7-megapixel wonder that you can take diving without a case. I wrote about it before, marveling that you can take it way deeper than its rated 33 feet. I took it down to 67 feet in the duckweed-covered Catfish Hotel sinkhole in Florida's Manatee Springs state park. Its built-in depth meter stopped at 33 feet and the little camera protested, but kept on working. Water pressure pushed in some buttons so that functionality was a bit impaired by flashing and beeping at greater depths, but it never missed a beat and no leaks.

So last weekend Carol took another Olympus 770SW with her as she conducted checkout dives for an advanced NAUI class at the Loch Low Minn quarry in Tennessee. She wasn't very familiar with the camera yet and most of her attention was on her students as they did the deep dive part of their advanced class curriculum. The quarry is about 80 feet deep and the bottom was pretty murky with visibility down to 10-15 feet, if that. So no pretty pictures this time, but the 770 saw a depth of 77 feet. In fact, the picture above was taken with it.

How did it do? According to Carol, the buttons on this one didn't get pushed in by water pressure and all controls worked even at nearly 80 feet. What did happen was that the water pressure apparently pushed in the glass of the LCD enough to cause a black rectangle in the center of the 2.5-inch display. It disappeared as she ascended and the camera was none the worse for wear. And no leakage either. That's just amazing.

Does this mean cameras like the Olympus 770SW will replace bulky underwater cases for compacts? Maybe. If the 33-foot-rated 770 can be taken down to almost 80 feet and still work, it's probably possible to make one that can handle the recreational diving depth limit of 133 feet. And with Olympus already having taken the big step from 10 feet with their Stylus 720SW to 33 feet with the Stylus 770, I wouldn't be surprised to see the next one rated at 66 feet (which means we'd take it to 133).

Are there other issues? Yes. It can get cold down there and that may mean gloves. Carol said it was difficult to operate the tiny little buttons on the 770 SW with gloves on. Deepwater cases always have those big plastic pushbuttons that are much easier to operate with gloves. It also gets darker the deeper you go, and reading all those tiny icons and writing that already virtually impossible to decipher in bright sunlight on the surface becomes next to impossible. No problem if you really know your camera, but with a mask on and bubbles around your head and other things vying for your attention, nice large and readable labels come in handy.

Anyway, I am just thrilled with what Olympus has done with the 770 SW. But what about flash, you may ask. Built-in flashes are generally useless for anything but macro photography underwater due to "scatter," i.e. the flash illuminating all the stuff that always floats around in water instead of the subject. Well, that can be fixed by having an external flash, and Olympus just introduced the UFL-1 Underwater Strobe, rated for 133 feet. It's a slave flash which means it does not require a cable connection to the camera. Very cool, and I can't wait til I get to try one out.

Posted by conradb212 at 11:14 PM | Comments (0)

June 13, 2007

My other passion

I often bemoan the fact that I cannot go diving whenever I feel like it. Well, actually I technically can as I have a nice pool in my backyard, but that doesn't really count. It does and it doesn't. Anyway, tonight I indulged in my other passion, racing cars. So if you have no interest in cars whatsoever, this entry will not be of much value to you. To me it is a hobby and passion like scuba, something that enriches my life, gets my adrenaline pumping, and just generally makes me feel good. There are also a number of parallels to diving, and so I want to explain what it's all about, and why it is similar.

When I say racing cars, I don't mean extreme racing or anything exceedingly expensive and dangerous. For me, it's mostly just going to the local drag strip, Sacramento Raceway, and participate in the Wednesday Night "Fun Drags." What's drag racing? It's very simple. There is straight track with two lanes and it is a quarter mile long (plus another eight of a mile or so to slow down). Two cars line up and wait for the lights on the "Christmas Tree" to count down. You slowly drive up until light sensors detect the front wheels of your car. First one yellow light comes on, then a second. That means you're "staged." Then, in half second increments, three more yellow lights come on and then a green one. On green (or really a bit before, as it takes the wheels a bit of time to move past the sensors) you take off and race down the track. Whoever crosses the finish line first wins.

What's so exciting about that? Well, speed and acceleration must be primal urges or else there wouldn't be ever faster cars. Is there any rational explanation why vehicles you can buy in any showroom can go almost 200 miles per hour when the speed limit is 65 or 70? Speed thrills, apparently, and speed and power have become status symbols. But it kills, too, and that is why there are race tracks. I never race on the street. But I love to go to the track.

How did this get started? I really don't know. I've always loved cars, and I used to go to the local drag strip when I lived in upstate New York. Lebanon Valley Dragway was nestled in the woods of rural upstate, a good distance away from any civilization, and it was fun. I really didn't think I'd ever race myself, and I wouldn't, not for another 20 years.

In 2003 things didn't look so good in my life and rather than moping I made a somewhat frivolous decision. I cashed in a CD and bought a brand-new 2004 Acura RSX sports coupe, cash. I had never actually driven one other than in a Microsoft XBox video game called "Project Gotham II," but I've had Hondas before. The sales manager loved the story. A customer buying a car without even driving it, just based on a video game!

It was a nice car, all black metallic with a blueish sheen to it. I always research things, of course, and within days I became a member of ClubRSX.com, a website devoted to the car. Little did I know that this would start me on a trek where I'd become an almost instant expert, write thousands of posts, extensively modify my car, and write "FAQs" (a web notation for "Frequently Asked Questions") on electronic engine tuning and then on superchargers. Yes, within months I became obsessed with learning as much as I could about that car and how it could be modified. I got into ECU tuning, which is the science of altering the programming of a car's computer to make it adapt to modifications and to make more power. I attended a seminar by a company called Hondata that specialized in automotive computer programming, had hands-on tuning sessions, attended a performance tuning class, and spent a lot of time and money systematically modifying my car. First it was just replacing the air intake with a more efficient one, then came the exhaust header and the exhaust, the suspension, the computer, and so on and so on. I documented everything, engaged in discussion, wrote how-to's for everything I did, and soon became a source of information for others.

Eventually I got into more serious stuff. You can gain a lot of power by adding a turbo or a supercharger to a motor, and I became fascinated with superchargers. Now we're getting into something divers can relate to: compress the air and you have more oxygen molecules. More oxygen molecules mean you can burn more fuel in your engine and thus make more power. And just like there is an optimal gas mix for every depth and just as there are limits as to what you can do before things get dangerous, it's the same with internal combustion engines. They like a certain ratio between air and fuel. If it's too lean there isn't enough cooling and the engine gets hot and can blow. If it's too rich, well, then it cools okay but won't run right. It's a science.

In car tuning, there are different cliques. Some go for cool looks. Others for handling. I was drawn to speed and power. In those circles, what an engine can do on the dyno matters. How much extra power did those modifications yield? A dynamometer, or "dyno," is a machine that measures how much power a car's engine makes. That's for bragging rights. The other thing that matters is speed. Not "kills" (accounts of street races won), but actual results on the race track. You get a time slip there, and it does not lie.

It took me a while to muster up the courage to actually go race. Just like scuba, it seemed all so complicated, with all those people milling about, knowing exactly what to do, whereas to me it looked incomprehensible. So one afternoon I went, asked a lot of silly questions, and then it was time to race. Adrenaline made my heart pound as I rolled onto the track for the first time, not unlike I felt when I took my first breath underwater. Just like in the pool, I knew it was going to happen, I was going to do it, it was inevitable. I did lousy on my first run, but it was so much fun. I did much better on my second, and before the night was over, I had taken on and beaten a bewinged Nissan 300ZX that did vicious burnouts. That victory was immortalized on video by a friend. It is now on YouTube. Oh, I forgot to mention: I did not take my supercharged Acura racing that first time. I took my lowly Chrysler PT Cruiser. It has a turbo motor and is modified, too, so it is not slow.

So that started a new era in my life. I went to the track almost every Wednesday and actually won four trophies in my first season, two outright wins and two runner-ups. It was the thrill of victory and the agony of defeat, and it wasn't even very dangerous. Even a highly modified supercharged car like my Acura RSX only reached a speed of 105 to 110 miles per hour or so at the end of the quarter mile.

I became a member of the NHRA, the National Hot Rod Association, the primary sanctioning body of drag racing. Would this lead to the kind of escalation I see in scuba, where open water certification leads to advanced diving, specialties, and ever more daring and dangerous exploits? It very well can. There is almost no limit to drag racing. The fasted dragsters are fire-breathing, earth-pounding monsters with thousands of horsepowers. They run the 1/4-mile in little more than four seconds, during which they achieve speeds of over 330 miles per hour. Unthinkable you may say. But perhaps no more than Sheck Exley and Dave Shaw penetrating caves and descending to deepest depths, and technical divers ever pushing the limits of what is humanly possible.

Did it lead me there? To extremes? It didn't. I participated in a few "points races" and decided it was not for me. I loved working on my car, adding modifications, discussing them, but I felt no desire to go farther. It was a hobby that gave me pleasure and I spent a lot of time and money on it, but I felt no need to go to extremes. Will it be the same with scuba? The two are really similar in many respects. I guess I will find out.

Posted by conradb212 at 11:14 PM | Comments (0)

June 06, 2007

Missed Scuba Show 2007!

Scuba Show 2007 took place June 2nd and 3rd at the Long Beach Convention Center in the Los Angeles area. I really wanted to go. Even in this day and age of the web with its instant information delivery, trade shows are still special. You get to see and touch stuff, meet people, ask questions, collect brochures and just generally immerse yourself in the conference experience. It isn't always pretty. It costs a lot to get to a show, stay in some hotel, get to the show, find your way around, and then glean as much useful information as possible. Sometimes it's deadly. I used to attend 10 to 12 technology shows a year when I was still doing the print magazines. I have plenty of memories of getting stuck in airports, fighting with hotels who always seem to find an excuse to jack up rates because "we have several major shows in town this week." Always waiting for a cab, waiting to get in, waiting for lunch, and then waiting to get a cab or bus back to the hotel. That seems to take up much of the day. And yet, I mostly remember the good stuff. Those moments when I saw a brand-now, exciting product, met enlightened people, took copious notes and hundreds of pictures, attended (and sometimes presented at) seminars and, of course, made all the press parties. Yes, it was possible to spend an entire week in Las Vegas for, say, Comdex, and not spend a single cent on food or drink. That's what press rooms and press parties were for.

Anyway, it's been a while since I've attended a big show. These days the big 24-inch wide screen of my iMac is the show. It's Information Central where the news arrives from all over the world, in an instant; where I gather and compile data, blogs, specs and press releases; where I scan image libraries, weed out chaff, process pictures, write stories. I get as much, or more, relevant news and it's a lot cheaper this way. Traveling isn't fun anymore what with all the security check hassles at airports and all the lost luggage.

Still, I had missed DEMA in Orlando last Fall, and I really wanted to make Scuba Show 2007. Long Beach is just a six or seven hour car ride from my home in Sacramento. I knew I wouldn't have the time to go down there, leisurly attend the whole conference including seminars and parties (some day I will!), but at least drive down, take in as much of the exhibits as I could in six hours or so, then head on back, perhaps crash in a cheap roadside motel if I got tired.

I really wanted to go, but work got in the way. Several major projects needed to be finished and so it came down to the wire. I would have to leave very early in the morning Saturday to make the exhibits which were open from 10am to 6pm. Friday night came and work wasn't done, but I was close. Got up very early Saturday morning, checked email, then had to make the decision (yes, I make decisions the very last moment).

So I decided to look at the Scuba Show brochure and see who exhibited. 11 scuba gear manufacturers, but only two or three of the majors. Oceanic and Aeris were there, but not Scubapro. 19 exhibitors in underwater photo and imaging. That sounded interesting, especially since my friends at Olympus were there, and we often review their underwater gear. 14 local dive shops. 17 non-profits engaged in some sort of worthwhile diving related causes. 15 presented some sort of instruments or technical and special gear. Seven sold books, magazines or were scuba websites. Ten did apparel, from T-shirts to drysuits. Two sold dive insurance. Ten had various accessories. Another ten seemed unrelated to the industry. Now for the big one: almost 90 were travel related. That included trips, dive resorts, tourist chambers, live-aboards hotels, agents. Bottomline: Almost half of the exhibitors at Scuba Show 2007 were dive tours, hotels, or resorts. Add the local shops, and it was more than half.

A great mix, for sure, but in the end one that tipped the scale towards not going. I love dive trips and plan on going on many. I support local shops. And I most definitely love gadgets and accessories and all. But with just a very few of the actual Scuba gear manufacturers being there and showing their new stuff, I could not justify it. I know it would have been fun. I'd probably have spent most of my time at just a few booths, taken lots of pictures, picked up lots of catalogs and brochures. I'd have been awfully tempted to go on a trip and perhaps someone would have talked me into signing up for one. Or three. I probably would have spent money on some gear, bought a new mask or fins or maybe an underwater camera housing. I would have cursed myself for not allocating more time and resolved then and there to do it right next time. I'd arrive the day before. Attend seminars. Mingle, learn. See all exhibits. Attend the parties. Stay for the entire event.

So I didn't go and missed out on an adventure. Driving 12 or 14 hours to and from and seeing a show is an adventure. Our ScubaDiverInfo.com and its rapidly growing number of site visitors would have benefitted as I would have put up a major Scuba Show 2007 report. As is, there is essentially no press coverage. Four days after the show, Google News shows nothing on "Scuba Show 2007." My bad. I should have gone. It's what I do. Scoop out cool new stuff, learn about it, use it, write about it, tell others in my magazines (in the past) and on my websites.

Next time for sure. I WILL go to DEMA this year, and Scuba Show next year!

Posted by conradb212 at 11:13 PM | Comments (0)