Navigation tips?

[gr8jab]

Hi all,

One of the areas where I feel the most anxiety is navigation. I do OK once I get familiar with a site, but other than CocoView, I don't dive the same locations frequently enough to learn them all. I can't wait for personal INS!

After a guided dive, I've often thought "I would never have found the boat!"

I've watched the PADI navigation video, and found it somewhat useless. I've heard a few strategies from instructors and here on the boards. Can anyone add to them?

@The Chairman : Do a 'Navy Seal Peek' out of the water to get a bearing. OP comment: I like this one in some cases where I'm already shallow, but don't like the idea of coming up from +30 feet to peek. Plus I have to already be close enough to the boat to see it.

@boulderjohn : On your descent you take note of your compass heading and a prominent landmark at some depth along the way. You come back at that depth, find the landmark, and follow the reverse azimuth to your starting point.

@boulderjohn : I knew the boat was moored on the top of the reef at 15 feet, so all I had to do was make sure I was at 15 feet by the time we got to that vicinity, and I was sure to find the boat. OP comment: not sure I totally follow this logic, since this is less exact that I would want. Lots of the reef is at 15 feet, even away from the mooring line.

@gr8jab : At night, I've mounted a spare flashlight and/or strobe at the shore exit.​

 

[nolatom]

Use your compass *before* you "need" it. Practice out-and-backs in the park.
In an anchored boat, note its compass heading before you splash in. That's probably the direction you want to go as you leave the anchor line, since it's likely to be up-current, so you'll have a less strenuous/stressful time on the return leg. Align the bezel (the rotating pointer ring) to where you are heading, so when you turn 180 degrees to return, you'll see the opposite pointer for the return compass heading. Just do this out-and-back pattern til you get more confidence--which you will.

Look behind you a couple of times on the way out, so you'll know what it's going to look like on the return trip.

Don't go too far away at first--short out-and-back, repeat, repeat, are much better than going way out and then getting lost coming back. Take note of the current and angle into it a little so you don't get set sideways.

Swim in good vis to start with. And with a good buddy. Being lost is less awful if you're both lost ;-)

 

[swimlikethefish]

Get a compass and practice in your backyard. In the beginning it helps to swim straight out, turn around and straight back. Then work up to swimming in a box. Out, left, left, left. I use the timer on my computer to aid in swimming different directions.
Example: straight out for 5 min, turn left, swim for 5 min, turn left, swim for 5 min, turn left, swim for 4 min, start looking for anchor.

To progress: I also account for current while drifting. So for instance if I swim into the current going out for 15 minutes. I might only swim back for 10 minutes before covering the same distance.

A compass is your friend. Use it until you are comfortable. Take it grocery shopping. And practice as you walk the aisles.

 

[scubafied]

All of the above are excellent suggestions and are more than likely exactly how your "guide" learned to dive the site as well. In a new area you could always try to dive the site in a specific shape (square, triangle) trying to mimic # of fin kicks in each direction. If you combine that with the above you should end up pretty close to your start point. In reality most dive sites are rather small and you shouldn't be covering vast distances unless you're drifting. My 2 cents.

 

[swimlikethefish]

In addition:

Even the most experienced get lost from time to time. Your divemaster and instructor are just really good at faking it. If they say otherwise they are liars.

I got lost last week at a familiar dive spot that I have done over 75 dives at in the last 6 months. Sometimes you get side tracked and forget to pay attention to where you are headed. It happens, don't become flustered.

 

[icechip]

+1 on the seal peek.

 

[tbone1004]

@gr8jab make a navigation slate like the one below. On it you can plot out a "rough" not necessarily to scale map of where you are going to be diving. On it should be any identifiable features whether catching features or landmarks and general bearings. In the area above the compass, you can see where you are and roughly where you need to go to get close enough directions without having to spy-hop and shoot a bearing. On the right side, or the back you can write a list of "common headings" for that site if you have a halfway decent map of the area to look at. Since it's all done in pencil, you can easily erase them at the end of the day and get the next site on there.
Bit more difficult if you're boat diving and don't necessarily know where you're going, but you can write any notes the DM's give you and look at them to create a mental map while you're down there

 

[Bob DBF]

It really all boils down to how much attention you pay navigation as opposed to watching the pretty fishes, or whatever else. This is especially true if one is new and still working on making diving skills subliminal. It's about bandwidth and how you use it.

Even if you don't want to do a nav class, you can sometimes pick up a nav manual on eBay, or similar site, cheap for a DIY course.


A compass can go bad, I had one drive me nuts and had me wondering about my basic skills untill I caught it. It was very slow returning to north, at first, then didn't make it to north at all. It worked normally out of the water, until the end. New compass, I was good at nav again.


Bob

 

[Bert van den Berg]

When you leave the boat make a note of the depth. Then use your compass to head in a certain direction (e.g. North). Try to stay on that course and not vary from that direction too much. To get back to the boat follow a reverse course. This is the simplest method of navigation.

As you get more confident you can then vary the swimming direction a bit. For example, if you swam North for ten minutes the swim West for 5 minutes, then swim South for 10 minutes. You should then be about a 5 minute swim to the East to get back to the boat. At worst case you should return somewhere near the boat even if there is a bit of current.

 

[boulderjohn]

@boulderjohn : On your descent you take note of your compass heading and a prominent landmark at some depth along the way. You come back at that depth, find the landmark, and follow the reverse azimuth to your starting point.

@boulderjohn : I knew the boat was moored on the top of the reef at 15 feet, so all I had to do was make sure I was at 15 feet by the time we got to that vicinity, and I was sure to find the boat. OP comment: not sure I totally follow this logic, since this is less exact that I would want. Lots of the reef is at 15 feet, even away from the mooring line.

Both quotations were specifically talking about Bonaire and Curacao, where the reef is in the form of a steep wall. If you know something is at a specific depth, you will find it there on your return.