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russp
07-11-2011, 12:46
OK, Ive decided navigation is my weakest skill at this point. I can usually get from point A to point B if I never take my eyes off my compass and miss everything going on around me but that doesn't seem like the best way to be diving. Any suggestions? Either of technique or courses that I may be able to take.

DMWiz
07-11-2011, 18:23
Well, it depends on where you're diving and what you'e doing. I almost never use a single type of navigation during a dive. If going from point A to B for example: wreck to wreck and there's a bunch of sand in between, I just follow a bearing and go glancing at the compass every now and then.

Point A to B on a reef, I'll take a bearing of the direction I need to go, pick and object ahead of me that is in the path of the heading and swim to it enjoying the dive until I get to the object and repeat this process until I reach the point I'm looking for. Obviously the bigger/more distinct the reference object is the easier this becomes. Great visibility helps too :)

Shore diving my local beaches, I will only use natural navigation aids such as the reef 'cause I know they run north/south, the sand, depth and "land marks" or should I say "sea marks"? :D

If I have to do out and back on a reef that goes in many directions and I'm not familiar with it, I'll do a square. Or just go one direction then 180. The pick another direction and repeat.

But the single most valuable tip given to me was to go very slow, you can't get lost too bad if you don't go too far!
Finally, you probably know this already, but it's probably worth mentioning; getting focused in any one thing (the compass, taking pictures, hunting, etc.) is never a good idea. Always be aware of your surroundings!

If you have specific questions feel free to ask.

Chilly
07-11-2011, 19:47
PADI offers u/w nav as part of their Advanced Open Water course. NAUI offers something similar as well. Definitely worth learning these skills IMHO.

For a nav technique, I do a scan consisting of direction of travel, gauges (to include compass), dive buddy, gauges...repeat as necessary while counting kick cycles. It definitely came in handy after some drama while diving a large wreck in limited vis.

DiveHard
07-11-2011, 20:34
I find using a compass mounted on a re-tractor slate allows me to log headings, times and PSI. Combined with a watch or computer that will alarm at a set amount of time will help in timing legs without counting kick cycles. Certain conditions such as current are factors that must of course be adjusted for. If you have a local park or field with plenty of open space you can practice with a towel over your head compass and watch. Write down a heading then decide a set amount of time for each. Using simple math you can plot many headings. Attempt to find your way back to with in a few feet of your starting point. That will teach you to trust your skills and compass in near too zero vis. Then once you feel competent start using trees and landmarks for headings. If you want instruction there are many books available on the use of compass. Like any other instruction/instructor seek out the best. I found that my scuba instructor being a LT Colonel had mad skills with a compass. Really paid off for me with my instruction. IMHO Rescue and Nav did more for my confidence and competence as a diver than any other courses. X2 with taking things slow. Enjoy and don't be surprised if everyone starts following or wanting you to lead dives. Have Fun!

russp
07-12-2011, 14:01
I have found slowing down definitely helps but I still felt too locked into the compass (I'd hate for that shark to sneak up on me). Being in mostly lakes with low vis and few under water features, trying to sight on something along the way doesn't usually work well. My best work is when following a wall or other natural boundry that I know leads to something but that often isn't available. I did OK with navigation in OW and AOW but again, I was locked into the compass and the distances were pretty short. I'll have to check if NAUI has a nav specialty.

DiveHard
07-12-2011, 16:09
Approach the concept of Navigation with the knowing that your not going to be perfect. That the idea is to get you with in a reasonable distance from your goal. The lower the vis the lower the expectation I have for success. Not the opposite. As vis improves so will your navigation because you will then have more information to reference against your known headings.

As far as not seeing the shark... I have dove with them and even when you are purposefully looking for them they can and do come out of nowhere. My instructor friend in Jupiter was just bit and even though he saw the shark it bit him before he could do anything really about it except fight him off his leg.

General headings with timed legs will still bring you close to your destination or starting point. In low vis lakes if I come up with in 100ft of my starting point I consider it a success. If I miss an underwater target or goal..Oh well. Bad vis was more the reason I missed it than navigation. Just part of the dive experience.

Sometimes during low vis dives at our planned turn pressure we will ascend to 20ft and deploy SMBs for a safety stop. Do safety stop. Then one of us surface. Takes bearing to boat. Descends back to 20ft and follow heading back. Towing SMBs on the surface. Sometimes we are close other times not so. This is open ocean with relative vis where our destination is the dive boat. The boat knows then that our dive is over and our intention is to return. At times they will knock on the side of the boat if your going to pass them. Most often you can see the shadow of the hull from 20ft.

In a lake you or your dive buddy will likely be towing a flag which makes for an instant ascent line in open water.

Like everything else it takes time and practice to become comfortable. I found the towel, timer and field practice worked the best when I couldn't get under. You may get some weird looks from people but when they ask what your doing you have a great conversation starter. A diver out of water... Happy safe diving.

Clernix
08-28-2011, 08:09
I was going to ask this same question this morning as always the info is already here. I am DM cert but that was over 20 years and 60lbs ago (and about half a head of hair).

For 20 years I have been diving in marine parks with a local guide and have completely lost these skills. I am going to Curacao in six weeks with my son who will be a new diver so I need to brush up on these skills since we will be soloing diving. Going to the park sounds like a good idea. I figure I'll work on squares and triangles and stick to those two.

Tom H
08-28-2011, 16:57
My shore diving usually doesn't involve going to a specific spot. My compass bezel popped of a while back, and before replacing it, I just used a general direction ei. ESE, or just keeping the needle between E & S, but closer to E. Not exact, but you don't have to check it that often, or keep your lubber line pointed. I think when using the lubber line & keeping the needle on N, sometimes I brush against the bezel and all is lost. Of course for precise navigation you'd have to do it the conventional way and just be careful not to move the bezel unless you want to. Currents play havoc with the compass, so other stuff comes into play.

buton
08-31-2011, 13:08
This is the next course I will be taking because I then it is very useful, there are some places where i am not going to dive with a dm like in the texas flower gardens, you are by your self there....

Necklinsberg
09-05-2011, 18:36
Consider practicing on land until the skill becomes second nature. Once you become more confident on how the compass will work, you might be more relaxed about using it in water.

In water, consider breaking up the navigation with you buddy -- one of you look frequently (but not necessarily continuously) while the other monitors depth while you swim side by side.

SynCitizen
09-05-2011, 19:19
Practice, practice, practice... taking the nav speciality is a great start then practice some more.

I know nav is one of my weakest skills in diving. I've been out practicing quite a bit recently in a familiar cove out at lake mead and each time I go out I get that much more comfortable and accurate.