Sunday 21 December 2014

Scuba Tech Diving Centre: Last video of 2014

Friday 19 December 2014

Finding your Path- Underwater Navigation in Scuba Diving

So, last week we started a blog series with regards to underwater navigation. Essentially, the concern is that we are training Scuba Divers to go Scuba Diving with a similarly qualified diver but, with the very limited Navigational Skills training on the initial training course, can we really say we have given them the tools they need to dive without a guide!

Now we will start to look at Navigation techniques that divers (of all level) can employ to find their way around a dive site, starting with the most common tool... Underwater Compass!

Underwater Compass

An Underwater Compass is usually liquid filled and the important elements you need to know about include; the Bezel, the Lubber Line, and the Card, which has graduated degree markings and the North Arrow.

Although it appears that the card moves, it doesn't. This is why the North Marking will always point North. The Compass housing actually moves around the card.

How do we Set a Heading

We like the Suunto SK-7 model, as it is very easy to use, so the instructions below are for this model. It is an indirect reading compass, which means it has degree graduation markings arranged clockwise on the Bezel, with 0 degrees (North) coinciding with the Index Marks. The card itself will show 180 at the top of the North needle... hence indirect!!

To use the compass, a diver simply turns the Bezel so that the direction heading we want to take sits at the top of the Lubber Line (which shows our direction of travel). You would then turn yourself with the compass so the magnetic needle sits between the index marks again and the Lubber Line remains aligned with the centre of your body.

So, if you want to take a 30 degree heading, turn the Bezel so 30 sits at the top of the Lubber Line (furthest away from you). Then turn yourself and the compass together until the North needle on the card sits between the index marks.

If that all sounds too complicated to you, you are probably over thinking it. The biggest problem I find with students learning to use a compass is that using it is simpler than they think. So, even though we spend ages practising on land before getting in, add water and they think they must be doing it wrong because it is too simple!

For a reciprocal heading, turn the bezel 180 degrees to head back the way you came.

To Navigate a square, the bezel turns 90 degrees (add or subtract depending on whether you want to turn left or right) while for triangles make 120 degree changes.

Things are even easier now with the advent of digital compasses that many modern computers
include. The newest of which is the new Shearwater Petrel 2.

It doesn't get much easier than this!

Some tips for using a compass for navigation on your dives
  • Trust your compass. It is more likely that you are wrong than it is
  • Hold the compass level 
  • Be prepared to navigate around obstacles and account for currents etc
  • Don't forget other essential skills such as buoyancy and air consumption. It's very easy to get transfixed by the compass to the detriment of all else.
  • Practice with it so you are confident

A very handy tool to use but not the be-all and end-all of navigation, especially in clearer waters. Still, it is essential all divers know how to use a compass to find their route.

Thursday 11 December 2014

Finding your path underwater-Navigation for scuba divers

Diver training can vary enormously depending on where you train, who your instructor is and what they believe are the important skills for you to master.

Underwater Navigation is taught in the PADI Open Water Course but it is only really "touched on" and not explored in detail. Divers must navigate a straight line on the surface and then a reciprocal heading underwater. Ask divers if they know what a Bezel is and the majority will look back at you with a blank expression.
diver with compass swimming into shark's mouth
And yet... we are telling these divers that they are now certified to go Scuba Diving with a similarly
qualified diver. Have we really given them the tools they need to dive without a guide?

Over this series of blogs, we will look at Navigation techniques that divers (of all level) can employ to find their way around a dive site.

But first...

Why is Navigation an important skill to master?

When we dive, we like to go and see the points of interest. This could be wrecks, reefs, caves, certain flora or fauna or anything that strikes your interest, really.

Without navigational skills, we would be just swimming aimlessly, unable to find said attractions. On land we use our GPS or Tom Toms, don't we? These do not work so well underwater, so we use other means but the basic need is still there. We need navigational skills to find our route.

If we know where we are going on a dive, we can conserve breathing gas because we can find our way directly to the attractions, rather than wasting air going in the wrong direction. This will then give us more time to enjoy what we went down there to see.

For the same reasons, we can save on precious minutes eating into our No Decompression Limits.

diver swim on the surface
Avoiding Long Surface Swims  is another benefit of being able to navigate underwater. It is a lot more tiring (and boring) swimming on the surface than gliding underwater, so if you have the skills to navigate to and from the attraction underwater, you should have a lot more fun!

Divers that know where they are going tend to experience Less Anxiety and Confusion, which is always a benefit when scuba diving. We have enough to deal with underwater without unnecessary stress in the mix. Read more about the stress spiral here.

So, navigation is a very important skill that we should learn and practice often. 

Don't get lost, check back next week when we will start to look at Navigational Techniques you can employ on your dives.

We will point you in the right direction!
Compass needle pointing NNE

Wednesday 3 December 2014

Dive Presents for Scuba Divers

When it comes to Christmas presents, we aren't hard to buy for, we the Scuba Divers of this world.

Anything that helps us get wet, stay warm and dry whilst getting wet, lights up dark murky holes, is shiny or can be classified under the terms gadgets and toys will surely be a winner wherever a Diver is concerned.

So, here is a Christmas offer from Halcyon Dive Systems to make you feel Festive this winter. This is the Double Down Christmas 2014 Bonanza.

The offer looks something like this...

Buy a Halcyon Infinity Single Tank Wing System for €895 (£715) and get an Evolve Twinset Wing for just €100 (£80).

The Halcyon Infinity System is the ultimate in luxury for the special diver in your life (or even if you want to treat yourself!). It has all the durability and reliability that divers worldwide have come to expect from Halcyon products and incorporates the opulence of the Deluxe Comfort pads for back and shoulders all combined with the Halcyon Cinch system for easy fit adjustments.

Of course, the system has the basics; wing, aluminium or steel backplate, harness and Single tank adaptor.

Use the Backplate with the Single tank wing or the Twinset wing and you are all set up for any kind of diving you want to do... all for less than €1,000.

For more information, just get in touch with us at Scuba Tech Diving Centre