Navigational Tips and Tricks

[Random Dude]

Hi all, was wondering whether you guys have navigational tips and tricks that are not in the manual, but super useful when diving?

About to take both the Underwater Navigator and Search and Recovery Specialties, and saw quite a lot of useful tips in the manuals

For example, waves breaking in isolated spots usually indicates a shallow spot, sea fans usually grow perpendicular to the current, colour changes in waters indicate depth changes etc.

Would be cool if you guys can share tips on navigation, anything ranging from natural navigation, tips when using navigational patterns, to compass usage etc.

Looking forward to your answers!

 

[Storker]

Carry a compass.

Some folks prefer to have the compass on on a retractor, maybe fixed to a slate. Others prefer to have it on their wrist. Find out what's best for you.

If you carry the compass on your wrist and use a soft Goodman handle for your light, don't put the compass on the same arm as your light.

A bungee mount is perhaps the best choice for a wrist-mounted compass.

Make sure to hold the compass horizontal when reading it. Different brands and makes have different sensitivity to being held at an angle, but every compass dial will eventually quit rotating if the angle is too big.

If your compass tells you that you're heading in a different direction than what your "natural navigation" says (and you know that the dial is rotating freely), trust the compass, not your opinion.

 

[kablooey]

Use your compass to establish some important bearings before entering the water.
Such as direction to target, direction to shore, direction back to boat or shore, direction to any hazards, etc.

A compass is pretty useless if your first look at it is when you're underwater and lost.

 

[MargaritaMike]

Don't put a wrist compass next to a wrist dive computer. The metal/battery in the computer may skew the compass heading. Keep any ferrous metal as far away from compass as possible. Test your compass above water as you would wear/use it underwater to verify known headings.

Cheers - M²

 

[Rhone Man]

Two tricks I have always used:

- be aware of where the sun is at - use it to keep yourself broadly oriented.
- if you are at a point you need to come back to (like your anchor line) make a note of your depth. Most dive sites are not on a horizontal plane and it is a lot easier to find your way back to a spot if you intersect depth with bottom.

 

[tursiops]

Test your compass above water as you would wear/use it underwater to verify known headings.

^^^This.
I taught an U/W Navigator class to a fellow who was quite competent and very technically oriented, and he could not even come close to the Dive 2 and 3 standards. I could watch him from the surface and see he was going in a perfectly straight line, in the perfectly wrong direction. We finally set his compass down on the wooden dock along with half a dozen other compasses, and they all pointed in the same direction (+/- a degree or two) except his; his pointed off about 15 deg from the others. I loaned him my compass, which had been used to set the courses, and he nailed it all, first try. Now, compass comparisons are part of my set-up before anybody gets wet.

 

[tursiops]

This is in the books/manuals, but a lot of people miss it:
If you've got a long run to make on a bearing, and especially if there is a bit of a cross-current running, and the distance to be traveled is beyond the viz, sight ahead to some landmark (like a coral head or a sea fan...not a fish!) on your bearing and then just swim to that point, and repeat, sighting ahead to another landmark on your nearing. The compensates for cross-currents, and means you don't even to look at the compass except at each landmark as you repeat the sighting.

 

[Bubblesong]

Something i do, for the sake of return trip familiarity, is look behind me every so often, because seeing the coral or whatever item looks completely unfamiliar from other side.

 

[Bob DBF]

^^^This.
I taught an U/W Navigator class to a fellow who was quite competent and very technically oriented, and he could not even come close to the Dive 2 and 3 standards. I could watch him from the surface and see he was going in a perfectly straight line, in the perfectly wrong direction. We finally set his compass down on the wooden dock along with half a dozen other compasses, and they all pointed in the same direction (+/- a degree or two) except his; his pointed off about 15 deg from the others. I loaned him my compass, which had been used to set the courses, and he nailed it all, first try. Now, compass comparisons are part of my set-up before anybody gets wet.

I had a compass that was only bad after it was underwater and reasonably deep. Drove me nuts until it finally acted up after a dive. I don't know if it was depth, cold, or a combination. Got a new compass and I'm back to navigating reasonably accurately. I have mine on a small slate with a retractor because it's light, I don't use it a lot, and if dropped it just goes home. The lubber line is extended onto the slate so I can hold it at an arms length ahead and below me at 45 degrees getting a good line of sight.


Bob

 

[Bert van den Berg]

Stop once in a while and watch the tiny bubbles and sand granules movement to get an idea of how much and what direction the current is moving you. If you can't stop in a fixed place, just float without moving and watch any fixed object to see same.