Each issue, a panel of RAID Instructor Trainers will give their insight into a specific topic, starting with the core skill of buoyancy
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teve Lewis, RAID Director Diver Training (worldwide) – A cave-diving student years ago was having problems with buoyancy. A huge contributing factor was the wetsuit he’d opted to wear for his course. Well, truth is, his problems were legion… but, hey, that’s a story for another day. What was memorable was an assumption he made about his instructor. “It’s easy for you,” he mumbled. “You mastered all this stuff ages ago… it’s second nature to you now.” I thought to myself: “Mate, if only you knew!” There’s nothing more true about diving than all scuba skills are perishable. And that’s the take-home message from this issue’s contributors – Ian, PJ, and Oli – real pros who long ago learned that the secret to making it look like second nature is practice. Practice and being careful to mess up only when there are no cameras (or cave students) around.
BUOYANCY
Olivier van Overbeek – Buoyancy is the force exerted on an object that is wholly or partly immersed in a fluid, or in diving terms, does it float, sink or stay neutral. Buoyancy control is what we keep ourselves occupied with as divers, being able to control the amount of positive buoyancy during an ascent or the amount of negative buoyancy during a descent gives us that feeling safety and confidence during these two phases of our dive and takes away the need for frantically holding onto lines, or not being able to stray from sloping bottoms. Further fine-tuning of our buoyancy control around the neutral point is what we desire during most of the bottom phase of our dive. At RAID we do not believe that buoyancy control is a standalone subject - after we’ve achieved a balanced equipment set-up, we can start working on buoyancy control, and with some practice we’ll achieve sustained neutral buoyancy. Simply having neutral buoyancy isn’t quite enough - once we’ve established an ability to sustain neutral buoyancy, we’ll look at a flat, trimmed-out position in the water and a good body position (the manipulation of this position can greatly influence trim control!). Once we’ve achieved all that, we’ve got a nice solid platform to work from and this is the point where we’ll introduce effective propulsion as a stand-alone skill set. This provides a diving platform where buoyancy and propulsion are truly separated, and streamlining is optimum. How does this look in practice? Well, the diver could stop their fin motion at any time, turn towards their buddy, and simply not move, not up, not down, not forwards, etc. This creates a calm and confident diver and an asset to the team. Once the diver has mastered this at a constant depth, they can bring this skill set to their ascents as well, allowing for comfortable, in-control group ascents where communication is easy and clear.
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OLIVIER VAN OVERBEEK Olivier van Overbeek (Oli for short) has been diving since 1998, and an active RAID Professional for over six years. His current roles within RAID include Training Manager for the UK, and Training Consultant for RAID International. He enjoys modernising and working on training materials, developing new techniques, and when not teaching or writing, thoroughly enjoys doing any type of archaeological diving.
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