Thursday, April 27, 2006

Deep air dive

The dive deck is spacious enough for four tec divers to gear up simultaneously. But right now it's just Michael and me. We'll be diving together, as it's my first dive of the trip and I haven't been diving deep for a while.

Suited up, double tanks strapped on my back, wings partially inflated, deckhands help me hook up the two deco stages, one on each side. After a last minute check, I duck walk the few meters to the ship's aft platform and splash in. A line runs from the bow to the stern and I immediately grab it, so as not to drift away with the current. Half pulling, half fining I make my way to the bow, where the down line is. This part can be a bit hectic and strenuous due to all the gear and the inevitable drag it causes, no matter how streamlined it is, especially if there're waves and current. But this morning it's not too bad. Still, we take our time at the bow to recover our breath before deflating our wings and start our descent.

↓ 5m. We briefly pause for a mutual bubble check and to pressurize our deco tanks before continuing on our way down. 10m. 15m. 20m. Down. Down. Down.

↓ 25m. Michael's already way ahead, pulling himself effortlessly down without loosing time. Descent time is bottom time. No sense in wasting precious minutes hanging around now. Steadily dropping deeper, I check all my gauges & instruments once again. 30m. The anchor line keeps disappearing into the blue below me. 35m. The wreck's still nowhere to be seen. 40m. Being on air, I can feel the first touch of narcosis. Suddenly, there she is. Just a vague shadow looming out of the blue.

↓ 45m. I pump some air in my wings to slow down my descent. 50m. We're on the wreck. Viz is poor, but Michael knows his way. I follow. It's as if the wreck is shrouded in a cloud of silt. I'm definitely slow-minded narced. I need to double check my instruments just to register what they're showing.

The wreck's alive with hundreds of small fish using it as refuge. Jack fish gangs dart in and out.

It being the first dive, we keep it simple. Staying on the outside, following the wrecks contours, just looking into the larger openings.

↓ 55m. Planned maximum depth. The bottom's maybe another 5m down, but barely visible. There're still some ammunition shells lying there in the sand. But somehow I don't particularly feel like messing around with those.

Soon it's time to return to the ascent line. We've been down for almost half an hour already. Narcosis sure has a way of playing with time. I guess it's because of my mind running at half speed, that time seems to pass twice as fast?

↑ Back at the line, we start on our slow way up. First deep stop's at 36m, where we switch from our bottom gas (air) to our deco mix (nitrox). Up 10m and another short stop. And up again. Then, from 18m onwards, we stop every 3m, holding on to the line to control our depth and avoid being carried away by the current - even though it's only slight at the moment. The narcosis actually sticks quite a while, my head only clearing up totally around 12m, long after I've left the deep!

↑ 9m stop done, we swim towards the deco rig below the ship, move up to 6m and switch to surface supplied pure oxygen to speed up the off-gassing of the nitrogen absorbed by our bodies during the dive. Still, it's a long wait just hanging there. Breathing in and out. In and out.

Time up, I let myself drift towards the ship's ladder, take off my fins and climb aboard. Michael's there already. Having a multi-gas dive computer, he can follow a real time deco schedule, in stead of a max-depth max-time pre-planned one, thus giving him shorter stop times. All in all it took me more than 50 minutes to come up. And that's for a relatively short shallow deep dive, with accelerated decompression.

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