|
 |
Diving - navigating underwaterBeing able to navigate underwater is essential to a diver's safety and the number one instrument that a diver will use in navigating underwater is the underwater compass, as this is an essential piece of equipment for the safety of the diver it is worth purchasing a costlier more reliable brand than a cheaper one which might let you down.It is important to remember that the compass can be affected by various things underwater such as variation and deviation which can be caused by magnetic influences such as wrecks or air cylinders. Underwater navigation is usually made using simple magnetic headings and there are basically 7 techniques which the diver should learn, these are: * Understanding the compass and knowing how to read and use it. * How to read "get me home" bearings. * How to make a bearing in relation to an object. * How to swim accurately on a bearing. * How to measure the amount of distance you have swam. * Reciprocal bearings. * Squares and triangles. Understanding the compass The underwater compass differs from the land type in that the north pointing is not mounted to a compass card, the degree scale and lubber lines are fixed to the compass with the lubber line and 000 degrees always facing in front of the diver with a rotating bezel containing the needle index marks. There are basically two types of underwater compass with both types being either wrist mounted, mounted on slates, an instrument console or they can be attached to a piece of kit. Whichever method is used it is important that the compass is centrally and directly in front of the diver, it is also important that the compass is held perfectly level allowing the north-seeking card to revolve easily. Get me home bearings This bearing is taken so that the diver can get home at any time during the dive and is relatively easy to set up and use, an example of this would be if the diver is shore diving and the sea is to the divers north or 0, if the diver was intending to swim north for 15 minutes then head south for 15 minutes, to set his "get me home" bearings he would simply turn his back to the sea rotating the bezel so the north seeking needle is between the two needle index marks. At anytime during the dive the diver then simply rotates so that the north-seeking needle falls between the two needle index marks and just swims in that direction. An important point to note is that once the bearing has been set then the bezel must not be changed. Taking a bearing to an object If the diver wishes to take a bearing to an object simply, point the direction of the swim arrow towards the object while holding the compass at eye level. Take a note of the bearing while by looking into the viewer window and ensuring that the swim arrow remains pointing at the object. |
Diving - navigating underwaterHomeScuba diving introductionScuba diving historyScuba diving certificationScuba diving suitsScuba diving equipment checklistEssential scuba diving equipmentDiving - decompression sicknessDive marshallingDiving safely & deeperHow to become a PADI certified scuba diverDiving - nitrogen narcosisPressure problems - Nonpulmonary BarotraumaScuba diving certification questionsSafely reducing air consumption when divingDiving safety tipsDiving - staying safe underwaterControlling buoyancy when diving tipsVisibility during the diveDiving & SharksYour real life diving stories - submit your own
The environment, eco system & our health |
Contact Us© Copyright Abyssdiveclub.org - Diving, scuba diving & snorkeling articles - All rights reserved. |
