Navigation for newbies

[Amberjack]

Hi all - A very newbie question about navigation and boat dives. Background: my husband and I have just been certified OW and in the slightly longer term, I'm planning on doing the AOW, but I think I'd like to get some more diving experience first.

In the dives that I did after my cert. dives, the boat chased our bubbles so we were always right by the boat when we surfaced - no problem. But from what I've heard, that's not how boat dives always work. I feel that the basic navigation skills we learned in OW aren't really sufficient. I mean, I can manage to plot a reciprocal course, but heading straight in one direction and then turning around and coming back - counting kick cycles all the way - isn’t really how people dive, right? :05:

My instructor gave a brief overview of using natural features to navigate by, but unless I’m really familiar with the site and the visibility’s pretty good, I don’t know how I’d do on that score. SO – sorry, long question – with the skills I have (ie, until I do the navigation course as part of AOW) how do we find our way back to the boat? Or do we surface wherever and make a surface swim to the boat? Or do we just hire DMs to take us around every time we dive? That last option doesn’t thrill me, because while having a DM would be great sometimes, I want to learn to do it myself! Or none of the above?

 

[Charlie99]

Or none of the above?

All of the above. Don't get discouraged. When I first started diving, all my concentration was on the basic mechanics of diving -- buoyancy and depth control, swimming, breathing, keeping track of one buddy. Kind of like first driving a car, the low level tasks like staying in your lane keep you fully occupied at first. Then more and more becomes automatic and your situational awareness starts getting better.

Some semi-random comments and hints that might help:

Go on some guided dives. See if you can keep track of where you are in relationship to the boat throughout the dive ---- just kind of keep a running track of "it's over that away about xx meters".

Do some dives in areas with very strong natural features, like a spur and groove reef. Navigation is really simple because as long as you remember which sand channel the boat is in, and how many spur/sand channels you have gone, then you can get back to the boat.

Take away some of the stress on navigating on a moored boat dive by going off in one direction for the first portion of the dive, then passing back past the boat/anchor/mooring around 1/2 tank and doing a mini-dive off in the other direction, or even just finishing out the dive doing small circles around the mooring.

Go with a more experienced diver, but with you leading the dive and doing the navigation. Only turn to him for backup navigation if you truly get lost.

Look BACK periodically as you swim away from the boat. Things look different looking the other way,.

Note where the sun it. If it's low in the sky, it can be an easy direction indicator rather than always looking at the compass.

Always start your dive going upcurrent. Try not to overshoot the boat coming back, and if in a current and in doubt about position, you are much better off surfacing early and upcurrent. Then either do a surface swim or descend to 10 or 15' for easier swimming.

It DOES get easier.

 

[Archangel]

Dear Amberjack:

Great question, lemme see if I can muddy the water a bit for you. You have skills yet untapped, and will be able to find your way back. As you are just starting out, at any time, you can come up from depth (20-30 fsw) find the boat, and then descend to start finning toward the boat (do it at 15 feet and it doubles as your safety stop). The only time you are stuck doing a surface swim is you have air pigged all of the O2 out of your tank.

The only time you dont ascend and make the most of your navigation skills is when you get certified as a deep diver and you are 80-110 fsw. That requires that you know where you are, and how to get back to your ascent line.

Also, down here in Southern California, there is always a pre-dive briefing given by the DM or Captain before we jump off the boat, so we know that if (for instance I go right, I will have a reef, and if I go left, I have a submarine canyon that drops to 320 feet).

No need to have a DM in tow, you are now certified, enjoy the Pacific Ocean and go exploring with yourself and buddy.

Here are some bone-a-fied navigation pearls.

1) The ripples in the sea floor sand made by the surge most oftentimes runs parallel to the shore (unless there is a longshore current or some other whacky thing).
2) If you are swimming along and it keeps getting deeper, you swimming out into open ocean abyss.

Happy diving,

Tevis

 

[Amberjack]

Thanks! These are terrific tips - can't wait to use them!

 

[DiverBuoy]

Not that I'm recommending shortcutting the need for real navigation skills and experience using a compass, natural contures, light, and other navigation aides ... but there are also devices (imagine a homing beacon) for the truely lazy at heart. You have the right attitude though in your desire to gain more experience and to continue your education.

Night diving can actually be easier to navigate back to the boat because even when the visibility isn't all that great the swim step lighting on most boats can be seen horizontally through the water a very great distance. Merely swim back to the lights below the boat and come up safely on the anchor chain or if you prefer an open water ascent come up to one side of the swim step - this makes for an easy "beginners" method to navigation.

Of course on some dives it is essential to navigate back to the anchor line or mooring line where current becomes more severe toward the top of the water column. See drbill's thread under the Accidents and Incidents forum from this week as an example of this hard lesson. In such cases where getting back to the line is critical there is no substitute for navigation skills and experience.

 

[TSandM]

It is a really good habit to get into, to set your compass before you start the dive for the heading that will get you back to shore . . . or back to the anchor line. That's pretty simple. If you sit at the anchor line and face the way you want to go, and set your compass for that heading, the reciprocal (180 degrees opposite) will get you back to where you started. (BTW, that's about where my navigating ability stops . . . )

Many dives have natural features that make it easier -- if the anchor line is at a mooring buoy on a reef, which way did you go along the reef? Which side was reef, and which open water? If you are on a wreck, did you start at the bow or the stern? What boat features did you pass, and on which side?

Compass navigation still makes me nervous, but natural navigation is getting better all the time. Of course, it helps if you dive in water you can see through . . .

 

[Diver0001]

But from what I've heard, that's not how boat dives always work.

What do you mean by this, Jack?

counting kick cycles all the way - isn’t really how people dive, right? :05:

No, you only do this when you're running precision search patterns. If you want to know how far to go back again, use your bottom timer.....10 minutes out - turn around - 10 minutes back. Account for current on a best guess basis and you'll still be close. As a bonus, the longer the dive is, the more accurate this method becomes.

I've written a couple of long posts about navigation in what I thought were really good thread that I'll try to dig up for you.

R..

 

[hvulin]

Depending on shape of the bottom you can try to remember the depth at which the ancor is. Go dive for X minutes (by rule of thirds) and then turn back (walls are the easiest, if you start with the wall on the left, then return with the wall on the right). As you go back, return to the depth of the ancor so you find it easily... (if the bottom isn't flat)

btw. take the course asap since it is a great course to learn...

 

[spectrum]

Unlike a shore dive where you may go out and back just to get to get to some depth and intersting stuff a boat dive should drop you someplace worth being. That said a spoke pattern can be used where you go out a modest distance and return then take a different heading for 5-10 minute of 500 PSI legs. This way you should not be at risk of staying too far on the return course.

If the terrain is good and not crowded with divers then some will clip a line off the anchor and swim a circle or arc, like a giant compass. It's a handy method when visibility is limited and you want to be sure to get back to the line. You can do a circle, reel in 20-30 feet and do a whole new circle path. I've heard of this as a search tool as well.

BTW while I'm comfortable with shore dive navigation I don't make my first boat dives until April. This is just stuff I picked up from other divers along the way.

Pete

 

[Amberjack]

What do you mean by this, Jack?


No, you only do this when you're running precision search patterns. If you want to know how far to go back again, use your bottom timer.....10 minutes out - turn around - 10 minutes back. Account for current on a best guess basis and you'll still be close. As a bonus, the longer the dive is, the more accurate this method becomes.

I've written a couple of long posts about navigation in what I thought were really good thread that I'll try to dig up for you.

R..

What I meant was that generally, the boat stays moored and you go to it, rather than it coming to you, which was how it worked for all my dives so far.

Again, thanks for the replies - they're reassuring! As far as doing the AOW goes, from other threads I've read, it seems like there's different opinions about whether it's best to wait to get more experience before doing it, or going ahead quickly - hence my concern about going straight to AOW after only 8 dives.