Navigation

[nereas]

If in a strong current, if in doubt as to whether you will spot the anchor, ascend to the surface before you reach the anchor and boat, not after.

I learned that one the hard way.

I have not learned that yet, Charlie!

Fortunately, as long as I have my X-Scooter with me, I can propel back to the boat from virtually any direction on the surface, together with the unlimited air supply of my snorkel.

Unfortunately, new divers do not normally have an X with them, to help them compensate for their mistakes with technology and power.

 

[Garrobo]

leejnd: I really don't care about becoming a more self-reliant diver. All I am interested in doing is getting wet and enjoying a dive now and then. As far as my buddy becoming distressed and in trouble, I'll help him/her out as much as I can without endangering my own life. Other than that, if things get out of hand, I know exactly how to send up a sausage, go to the suface and then look for the boat/blow a whistle for help, etc.

 

[TSandM]

Boy, for me, ten feet of viz, anchor NOT set into a recognizable feature (eg. wreck), and absolute requirement to ascend at the boat adds up to probable trouble, no matter how good your navigation is.

I had an experience when we were in LA, where we dove off an anchored boat in the shipping channel. We were diving a wreck, but the anchor wasn't set in the wreck. It was probably 75 feet or so from it, and the viz was maybe 20. We found the wreck without too much difficulty, but swimming back to the anchor line got a little nerve-wracking, as we kept going and going and no line was to be seen. We did find it, but we agreed afterward that it would have been smart to have run a line to the wreck for ease of return navigation. Of course, I was carrying my usual 50' spool, which wouldn't have sufficed . . . Lots of lessons there.

When I've had the ill fortune of ending up on a nondescript bottom with no line to run, I've just stayed very close to the anchor line, swimming a pattern that would keep bringing me back under or over the line at short intervals. Makes for a somewhat dull dive, but I can do without the excitement of a free ascent away from the boat.

You can get very good with a compass, but if the water is moving (current) and the viz is poor, it doesn't take much drift off your line before you aren't going to find that anchor again.

 

[MauiScubaSteve]

If the conditions dictate that you must go down the anchor line, then you should go all the way down the line, until you get to the anchor. At the anchor, you should stop and adjust your buoyancy and gear, as needed, and then SET your compass to point you INTO the current.

Then you should follow your compass INTO the current for 1/3 of your air/nitrox.

When 2/3 is left, you should turn around, and return WITH the current on the reverse azimuth on your compass. This should bring you back to the anchor line.

The other possibility is to stay near the anchor all during the dive, either on the pinnacle or reef that the anchor is set, or near enough to the anchor line so that you can see it.

The main danger is getting blown down-current of the boat. Then you will have a long surface swim back to the boat, or else they will need to come get you.

And if they dont come get you, and you cant swim back to the boat against the current, then guess what? You are then lost at sea. This happens several times each year to a few unlucky people around the world. Most of them die that way. The really lucky ones get picked up by another boat.

So be careful.

What if the actual dive site is not into the current from the anchor? If the general area of the dive site is down current just a little ways (but beyond vis), would you still start back to the anchor with 2/3rds of your tank? If your anchor is set in the reef in Hawaii someone will be pissed. Well the last part is right, do be careful.

 

[mattbinvt]

Keep Practicing...

 

[tonka97]

leejnd: I really don't care about becoming a more self-reliant diver. ...

You may want to re-think this attitude.

 

[glendivesalot]

The way I teach underwater navigation is to take people first to a basketball court. The angles on a basketball court are perfect for getting to know how to use a compass. Once one is profecient in using a compass on land, one gains confidence in using a compass. Then, you can take it underwater and it is much easier to use with that confidence and practice you had on land.

 

[mislav]

Hey Thanks for all of your tips. I think your all right , what I need is practice. And I'll make sure I swim up current!

It will come with practice, but as others suggested - it would be more helpful if you were to lead the dives. Following the group won't help much.

Speaking from experience - my navigation skills suddenly got better once I began leading the dives myself. My first dives were definitely "trust me" dives.

 

[Garrobo]

tonka97: Explain your statement.

 

[Leejnd]

Perhaps tonka is having a hard time understanding why someone wouldn't want to become a more self-reliant diver. In my case, it's been a priority for me to improve my dive skills, knowledge and safety. I don't personally want to always put my life in the hands of others, especially if that other person is a stranger (instabuddy) assigned to me by a DM. And while navigation skills may not seem like the most important of dive skills, some other posters in here have made some good points about the possible consequences of not being able to find one's way back to the boat.

I used to rely on others to navigate. That worked until I ended up with a buddy who said he could navigate, but really couldn't. It was kind of embarrassing when the chase boat had to come fetch us. :embarass:

Glendivesalot: my AOW instructor did something similar in a parking lot. I *thought* I knew how to use a compass...until I got there with him and learned that I really didn't. So much for Girl Scouts!