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Dive Logs for Vance Stevens PADI open water scuba instructor #64181 Dive 402 August 17, 2001 Abu Dhabi: The beach at the Sheraton |
Diving
with:Marina Divers
Dive buddies: Tariq Williams, Roald Van
Rensburg
Others in dive party: nil
Conditions: calm,
slight breeze
Visibility: horrid poor, maybe 2-3
meters
Wetsuit combo: lycra skin
Weight: 6 kg
Diving
from:Sheraton shore dive
My 402nd Logged Dive since 1991
Dive site: Sheraton shore dive
Training
conducted: Tariq Williams's OW Dive#2; Roald Van Rensburg's Advanced
OW UW Navigation Dive
Data from dive computer:
Time down on dive computer: 8:52
Max depth: 4 meters
Time started
up from chart: 64 min.
Dive time from computer: 56 min.
Min Temp: 33
degrees C (fatal to coral)
Nitrox 21% (normal air), no deco
PSI/Bar in: 200
PSI/Bar out: 100 bar
Pressure group out, from tables or wheel: HN
Description of dive:
Tariq, Roald, Russell and I all turned up before 8 a.m. for a planned dive to the Old Cement Barge. But when Wayne showed up at just after 8 he told us the engine on the boat was knackered, and the dive was cancelled. Russell decided not to pursue it further, but Roald thought we might as well get wet, so we did Tariq's 2nd ow dive and his u/w navigation in the shallow silted sand just off the Sheraton beach.
The above graphic shows the first part of our dive. As a dive it was pretty crap; we saw just one crab and that was about it for the wildlife dept. But as a technical dive it was interesting. Roald had been diving with Ali one week earlier when he did his advanced o/w navigation dive, so he'd aready done kick cycles and time over 30 meters. So we started with his compass work. Tariq got a bearing on a buoy marking off the swim area at the Sheraton and with him leading us head-underwater, we swam over to it, descended using the 5 point checklist. Roald's turn on compass, he led us west from there about 30 meters, we left a marker, and returned on the reciprocal heading. I followed my own compass course as Roald did his. He was slightly right off course on the return leg and he didn't stop at the end of 20 kick cycles. I was more accurate and came on the buoy anchor and line which was visible only within a meter, so I clacked Raoul to stop. He had missed it by only a meter and a half but should have stopped at 20 kicks to look for it. He understood my 'explanation' underwater and in gestures promised to stop next time.
We then attempted a square. Roald took us north, west, and east on 20 kick cycle legs, at which point we should have found our marker. Vis was abysmal and the sand bottom totally nondescript and subject to silting, so I wasn't concerned that we didn't see the marker where it should have been after the third leg. On the last leg east, Roald did 20 kick cycles and stopped this time. We didn't see the buoy but I had him and Tariq hold the end of my reel while I went out about 10 meters and then swam 360 degrees around them. Nothing to be found, so we surfaced and saw we were well off the marker buoy.
I decided we were in a bad spot that close to shore and we'd be better off if we went over to the swim platform where Tariq and I had reached 4 meters in training. I was hoping for slightly better vis there. My computer took this to be the end of our dive and produced the following graphic for the next one:
After we had swum to a buoy we dropped down its anchor line to where it was tied off on a concrete block with a pile of beverage cans just north of it. There for a change of pace, I had Tariq do his skills for o/w dive #2. He tossed away his reg and recovered it, half and then fully flooded and cleared his mask, and then did an alternate air source breathing exercise at bottom with his dad. Later, I took him to the surface on alternate air.
Roald then repeated the square pattern exercise. He led us to the north, but by my count only about 12 kick cycles. This threw me off a bit I think, and on his next leg to the west, I focused on how many kicks he was going. Again it was about the same number, so I figured we had a chance of ending in a square. Normally on this exercise I do my own square as the student does his, but because I was no longer doing the squares I might have become confused as to what happened next. I was thinking Roald took us south and then east, at which point we arrived at a bouy anchor, but not one with beer cans nearby. I had us surface to check our position (we came up on alternate air source breathing, me and Tariq), and we saw it was not the same buoy where we'd started. But now that we could talk, Roald said he'd only done three legs of his square. If so I was a bit remiss, maybe thinking because we were back at the buoys we'd completed 4 legs. But in that case if we followed a heading east we would not have arrived at the correct buoy since the line of buoys ran northeast. Nevertheless, what to do? I suggested he do a compass bearing on the buoy we were aiming for and take us there along the bottom, hoping to arrive on position in 20 kick cycles. We agreed to do this, and after 20 kicks Roald stopped in sand with no buoy in sight as he'd by now learned to do (in sight being within no more than 2 meters). This time I sent him with the end of the line in a 360 degree circle. He started to the east and turned to the north, and as he passed west of us I saw the line go slack so though I couldn't see him I knew he had come very close by us rather than keep the line taut at the outside of the widest circle. When the line again stretched to the south and east and he was beginning to repeat the circle, I called him back with a couple of tugs. As he emerged from the gloom I indicated he should check once more to the west where he had let the line go slack. This time he stretched the line and found a bouy and tugged the line to indicate we should come. He was at a concrete block with a buoy moored to it, but again I didn't see a pile of beer cans, so it was not the buoy where we had started. Under these extremely low vis conditions, the correct marker could have been just 3 meters away from where we had stopped, so I figured Roald had done about as well as could be expected. We'll have an opportunity to do more squares later I'm sure, in the course of another dive.
Now I had Tariq take us 20 kick cycles to the north of the buoy we were at and return to the same buoy as his u/w navigation requirement. At least I guess we arrived back at the same buoy.
On the outer leg of Roald's square we had come to a patch of stable sand with perhaps 3 meters vis, so I suggested we return there. We found the sand patch and from there headed northerly, even increasing depth in a trough of 4 meters. But as we climbed out the other side we pressure checked, and Tariq was getting around 75 bar (he had taken a tank with just 150 bar, as we discovered when we did our buddy checks at water's edge - he said later he hadn't known he should look for one with 200 bar - this is the first time I've taught the course without giving lectures, but letting the student self-study, so it's clear that beginning tank pressure is one knowledge tidbit that falls through the cracks on the self-study system). So I suggested Roald take us home. I wrote on my slate "Take us home, south-ish".
Roald led us due south. I guess I had noticed myself and esp from doing training in the area that the way back to the beach was slightly to the southwest, so a directly south course was taking us at an angle across the beach. As luck would have it, our southerly course took us across the Sheraton beach front and even past the jetty jutting out to keep it private from the rest of Abu Dhabi. We, or at least I, realized where we were when we turned up in the shadow of the dock with Marina Divers's knackered boat overhead. It all made sense after that, a return north along the stones of the jetty to come up around west and to the concrete ramp where we'd started our dive.
We surfaced (i.e. stood up) and swam out to deep water. To reach there, I had Tariq set a compass course on one of the buoys and swim there head down, exchanging snorkel for reg on the way. When we arrived (spot on; Tariq's compass work is good) I dumped air from my bcd and allowed that I was tired. Tariq responded by restoring air to my bcd. I then told him his dad had a cramp and he went over there and sorted that out, then did himself. Somehow this tired Roald out so I had Tariq tow him back to shore.
A bit disappointed when Wayne announced the dive was cancelled that morning, and not thrilled at shore-diving the Sheraton beach front, but it turned out to be an enjoyable and productive morning after all. We got wet, and beats the heck outta watching tv.
Surface interval:n/a
Pressure Group in: n/a
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