Underwater orientation

[Deefstes]

We do most of our diving with a DM who carries a buoy line. This means that we don't have any need really to pay attention as to where we are on the reef, the boat will be there when we surface.

I find it unsettling how, after 80 dives, I still have very little sense of orientation under water. I know of some tricks (like observing the ridges in the sand caused by water motion, paying attention to the prevailing current etc.) but would you guys mind sharing your experiences on how you developed an appreciation for finding your way under water? More poignantly, how do you find your way back to the anchor or permanent buoy line?

 

[Arizona_SVO]

Well, for me it started with the U.S. Army and learning to use a compass, natural terrain features, map, and something called a stride length.

Still use a compass, natural terrain features, site guide (some sort of book if available), and a kick count. However, current conditions sometimes modify that last part considerably. And practice, practice, practice. If it's really complicated, I will write it down as I dive - x minutes @ x degrees and so on - then go reciprical course. Staying at an even depth helps a LOT.

 

[Teamcasa]

Navigation is 40% observation, 40% recollection and 20% compass. Paying attention to where you are going and chances are you will find your way back. Navigation comes easier to some than others but it is a skill anyone can learn if they decide to. OTOH, it is a skill that can dissipate if not used. Practice, take in everything, learn how to use a compass.

Using a compass on land can and will improve your underwater compass skills. Make a course on land, take notes at each way-point and then return using only your compass and the note you took. You will soon be the "let's follow him." guy.

 

[DennisS]

A compass is a great tool, it's easiest in the beginning to run a straight course out and come back on the reciprical. You have to be aware of the current and compensate for it. Another thing is stop every now and then, turn around and see what it's going to look like on the way back.

Don't start out swimming for a half hour and turning around. Go out 100 meters, turn around and see how close you get to the anchor, repeat and repeat, getting further away. Eventually you will come back and not be able to find the anchor, if you're doing it right you will surprise yourself when you surface and the boat is right next to you.

 

[dkktsunami]

A good way to improve compass skills is to dive in a dark water lake where the compass is actually necessary to find your way around. Find a safe place and practice until it becomes second nature.

 

[MXGratefulDiver]

I use the three "D's" ... depth, direction, and distance ... to mentally build a "map" of where I am relative to where I started.

When you descend ... before you go anywhere ... take note of your depth. Terrain underwater is rarely flat, and in most cases, knowing the depth of your downline is useful information.

As you go through the dive, note your compass heading and use it to build a little "map" of where you are relative to where you started. In my classes I like to use the analogy of the old movies where someone is traveling and the movie pans back to a map showing a dotted line where the person is going. Every time you change direction, start a new line on the end of the old one in the direction of your heading. Keep a mental note of where that line is taking you relative to your starting position.

Distance ... this determines the length of your lines. There are several ways to measure it. Most agencies promote the use of fin kicks. I don't personally find that method useful, because it involves a lot of counting ... and requires you to spend too much concentration on something that detracts from your dive. I find elapsed time to be more handy. If you go off in a direction for six minutes, then you have established a line on your "map" of a certain length. If your next direction is 10 minutes, then you know the line in that direction is going to be longer.

Depending on conditions, you may have to compensate for things like current ... but using this method will usually put you close enough to allow you to recognize objects, or to get within your initial depth, when you return to find the anchor line. I've found this method to be useful in reasonably low-vis conditions ... to put me within 10-20 feet of the line I'm looking for.

... Bob (Grateful Diver)

 

[jmasin]

I would second the above regarding OBSERVATION. One thing I realized when being led on dives is I looked for cool things, I didn't really observe features and where I was. Diving on my own (buddies but not led) forced this to change quickly.

If you rely on direction of the current for one aspect, make sure you know the area, in Cozumel the current flipped on us twice on shore dives. Fairly common this time of year I'm told, and would have left us guessing had we not already known that was a possibility. When all the schooling fish suddenly change the direction they are facing it can throw you for a loop LOL.

On the night dives which I led (a first for me so a big deal for me ), I used the compass and got individual bearings on features on the bottom. The dive site made it a bit easy for me because there were easily discernible features, but I made mental note of features in a general line of direction, making it much easier to return. If I was off a bit, it was only for a 100 yards or so and I could realign. Of course 20' of vis with my light helped.

I'm with Bob on fin kicks too... probably because mine are not consistent, but that never (or not yet anyway) has worked for me... I BLEW by my target in the lake with low viz and I swear I counted right

 

[MauiScubaSteve]

The type of your body of water dictates many of your procedures. The night/lake example requires no bottom features. Almost any ocean dive (at least in Hawaii) requires using bottom features.

As a photographer, I always notice the angle of the sun; the best pics typically have the sun behind the photographer. Sun angle changes very little in an hour (unless you start dive at 11:30 AM ) so general direction during the day is always in my periphery. Between bottom features and sun angle I rarely use a compass, even on first dives at a new site.

Some of us are nearly always aware or our general location; it's not my fault that both my parents were geologists and topo maps lined my crib. Others will probably only dive navigationally challenging sites with someone like me navigating. The people who dive with me just take advantage and enjoy.

 

[TMHeimer]

"Point to Point" navigation can be a big help, and current is irrelevant. Set your compass heading to where you want to go, find an object (rock?) then go there. Re-check heading and continue to another object. Not good if it's all sand, all reef, etc. Keeping tabs on the anchor line is a biggee. Don't want to surface without a reference and far from the boat. Look back a lot when leaving the line. Make note of objects you pass. Compass may be no good on a metal wreck. Unless you're on a very intact wreck, there is no fail safe way, other than laying out a line.

 

[Jim Lapenta]

Another mistake divers will make when doing navigation is to try and do everything by themselves. I am pretty good at UW Nav. Wrote a course in fact. But that did not happen overnight. It took a great deal of work, time, and patience. I saw an instructor a couple weeks ago tell an AOW student to swim out 25 kicks and turn around and come back. Using a compass and a simple reciprocal course. He told him if he was within 20-25 feet or where he started that was close enough. Problem was he would not know if he was. Vis was 10ft or less. And there was a mild current that pushed a diver parallel to the shore line. I had my student do a 5 kick swim to estimate the current and amt of intentional error to use. We then did a square 5x8x5x what turned out to be 3-4 kc. Why? because of the current. Then we did an 8x12x8x5. On both occaisons the student came back to within 2 feet of the start point. It was not magic or even an unsual feat using the methods I teach.
1. you need to know how much if any to compensate and this is easy to determine
2. Don't try to monitor everything yourself. I can. After a couple hundred dives and working on it on every dive at some point. My student worked the compass and did SOME observing. I monitored depth, time, and distance. Navigation is a team skill as much as an individual one. And the team members should alternate responsibility
3. Make actual notes on a slate or wetnotes
4. when you pass a feature turn around and look at it. It most likely will not look the same coming back.
5. When making turns note the direction and make precise turns in the beginning. Stop, turn the bezel, helicopter turn, and swim. Big looping turns in the beginning will just introduce more error.
6. If your buoyancy and trim suck so will your navigation. Work on them on every dive.
7. Start with short easy courses and increase lengths over time.
8. Learn to really pay attention to time, pressures, and features, Kick cycles become pretty useless when you have to concentrate on counting more than say 25-30 of them.
9 Swim slowly. Forget about keeping up with a DM or Guide. Plan your own dive and do it. They get pissed too bad. They are not paying you to keep up.
10 Practice Nav on every single dive. Even when following a guide (which I absolutley hate doing) take a heading, note turns, watch your air and time. Do not expect to become good overnight. You'll just get frustrated. And learn to trust your tools. I can now swim in 5 foot vis for nearly an entire dive with no visual references and be comfortable. And usually come within a few yards of where I want to be. After swimming for 45 minutes. That does not happen over night. I wanted to get there so I worked at it. With buddies and alone. I'm still not where I want to be though. And that I think is a good thing as it keeps me working on it.