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REGARDLESS OF TRAINING AGENCY, most of us used a compass during one of our first open-water dives. Unfortunately, this was at a time when we were task-loaded to the max, and the topic of navigation probably did not get the attention it deserves.
     Post-qualification, most divers tend to avoid compass-use for fear of looking a fool. So it can often remain a key skill that is far from mastered.
     As far as I know, only PADI and SSI offer dedicated underwater navigation courses (Ill wait for the contradictory emails). As with a lot of training of this limited nature, most of us tend to think: Its just using a compass, surely there cant be sufficient material for a standalone course And so we move on to something else.
     But, as I was to discover when I did another PADI speciality course with Red Sea Diving College in Sharm el Sheikh, there can be a lot more to it than that.
     For this two-day course, we used instructor Terry Johnson, an experienced and well-respected member of the Sharm community.
     The theory part centred around PADIs Underwater Navigator manual, and lasted two and a half hours. The only additional deskwork would be the final knowledge review. The manual covers far more than you might think, such as how to map a dive site accurately and conduct an underwater search using a compass.
     There are many useful tips in the manual - along with one glaring error. The diagram that refers to making an underwater map of a dive site would seem to encourage the diver to make no fewer than 17 ascents and descents in the 3-14m range - that is, the place in the water column where most pressure changes take place!
     Im sure that this is simply an oversight, as the mapping method would be perfectly appropriate if conducted parallel to the indicated shoreline. But as this manual was printed in 1994, you would think PADI would have picked up on this potentially dangerous graphic by now.
     We also discussed the use of natural features (both above and below the water) and different ways of measuring distance. These included counting fin-kicks; arm-spans; time; tank pressure; and, the most accurate method, using a measured line or tape.
     The most commonly used method, however, is the kick cycle. As with most of these methods, its necessary to calibrate yourself with a known distance initially.
     The theory session does make you think about all the navigation aids you have available, from sun and shadow to sandbars and plant life. Which of these is available to you depends on where you dive. Sadly, for us, silt and mud do not count as usable natural features.

Dive 1
You might imagine that looking for lost objects in the Red Sea is likely to be an unchallenging pastime, even in the worst viz: Oh no, Ive lost my reel! Oh, there it is, 50m over there!
     A bit like looking for a haystack hidden behind a needle, really, so if instructors are to make this a valid course, they have to use their imagination. Unfortunately for me, Terry had managed to address this problem.
     As I had already done my PADI Advanced Diver some years ago, I opted to do the navigation course in one day and two dives. To calibrate my fin-kicks and time to an actual known distance, we started the day with a swim along a measured 30m line in the warm clear water of Naama Bay.
     I came out at 17 kick-cycles and 1:05 minutes to cover the distance, a useful fact to file away for future use, particularly in low-viz environments. Because of the drag factor, however, the exercise would need to be repeated if equipment was changed.
     Settled on the bottom, Terry handed me a slate, written on which were seven bearings and approximate distances. In theory, by following them I should discover seven weighted slates he had laid out in the bay. Should I not find one of these waypoints within the distance/time stated, I would have to navigate back to my starting point and try again. As I set my compass and headed off, I was rather wishing Id brought a twinset.
     To compensate for the excellent viz, Terry had chosen a virtually featureless site and half-buried the target slates, making them visible only when the diver came within 3m of them. As the standards for the course state that the student must navigate to within 5m, this was a shrewd move.
     Also, on two of the legs Terry swam ahead of me and threw sand up, reducing visibility to 30cm. I felt quite homesick.
     After I had completed Terences little tour, I noted down depth and features of our last waypoint before surfacing directly above and recording our position. This would be our starting point for dive two.
     I sighted three transit points on land and made a note of them on my slate. One of these was a TV aerial that lined up with a distant mountain peak and, as the manual said, I then took a compass-bearing as well.
     In theory, when swimming back later and keeping these two features lined up, I would be sure to swim in a straight line towards the drop zone until my other two transits lined up. Then, voila, I would be over my former finishing point.
     As we surface-swam back to the busy beach, I thought I could detect the characteristic tremors of a small seismic event, perhaps far out to sea. It turned out to be the beginning of the Italian womens aerobic session.

Dive 2
While I had a leisurely lunch and completed the knowledge review, Terry sat hunched over a distant table scribbling away on the weighted slates. He then disappeared in his diving kit for the best part of an hour to plant course number two.
     We met up with him in the shallows to begin the second dive. The large grin on his face did not make me feel confident.
     Once I had managed to work out which aerial I had used earlier and which bush lined up with the corner of the ice-cream truck, we made our descent.
     To my relief, the concrete block that signified the spot was exactly where I had left it, along with my first clue.
     The route I was to follow this time was not to be a list of bearings as before but a series of multiple-choice questions from this and other PADI courses, the answer to which would give me the correct heading. I could see this taking some time. This was not a standard PADI method but one of the little details Terry had made up to add a little interest to the course.
     As I struggled with the answers from my Open Water course, I discovered the little extras that Our Tel had thrown in along the way, such as semi-burying the slates and putting chunks of reef in the way so that I had to navigate a square pattern around and continue.
     However, the most devious trick he played was his final choice of question: What does Project AWARE stand for Needless to say, I then got to practise making reciprocal swims before getting the correct heading.
     Dive over, we checked out the reef for a while before surfacing for the end of the course after an eight-hour day.
     This PADI course is accompanied by the usual video which spends a third of its time telling you about other courses youd love to do, and an excellent manual.
     The navigation course hardly needs material other than for a students future reference, as it is about the practicalities of doing things under water - such as glancing at the compass only every 30 seconds or so, instead of glueing your nose to it.
     I cant think of many additional skills that would better serve a UK diver to practise, but without the impetus of a course structure, we are seldom self-disciplined enough to do so.
     The perfect place for regular practice is an inland site, perhaps during the off-season or when your sea dive has been blown out (again).
     I practise by taking the bearings supplied by Capernwray dive centre to create underwater routes to follow, and put them in a small self-adhesive laminate that can be carried on the compass strap. It does give quarry-diving beyond qualification added usefulness.

  • The PADI Underwater Navigator Course run by Red Sea Diving College costs US $90 (for two dives) + $45 for an extra dive + $30 certification. Contact the centre on 0020 69600145 or visit www.sinai-services.com

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