Question Search & Recovery vs Underwater Navigation

[Orso Raggiante]

I have always marveled at divers who basically show up at a dive centre, pick up their cylinders, and go off to dive at a particular site. I wouldn't know how to get to, say, a wreck, if I had dived that site just that morning! So I was thinking of doing either a Search & Recovery specialty or an Underwater Navigator specialty to help me locate myself and the things I want to see underwater. Does anyone have any recommendations as to how I can achieve this, or perhaps tell me the difference between the two courses mentioned? Both seem to teach some amount of measuring distance, knowing directions, and remembering features. Thanks in advance!

 

[Seaweed Doc]

How do you practice navigation in a lake with few features on the bottom? I was thinking of an SMB with a weighted line. Shoot an azimuth at the surface and follow that bearing at depth until I get to the line.

That's how you should do nav. Well, at least compass navigation. The elements you learn are things like this:

1. How many kick cycles does it take you to go 100'/30 m?
2. Starting at a fixed point (maybe the instructor?) you swim out and back using a compass.
3. Starting at a fixed point, swim a square and end up where you started using a compass.

The tougher one would be landmark-based navigation (which is taught as a skill). If the lake has a perfectly flat bottom, it'd be really tricky. If not, the feature you could use is a depth profile. Swim out and back holding this depth. I like to make it a little more complicated, but would need to drop a few objects here and there for students to use as waypoints in this situation. In my world, I can do things like tell them to swim straight down hill to 20', then follow that depth to the right until you find a corrugated pipe. Swim down the pipe to 50', then turn left and hold that depth until you find the target.