AOW Navigation dive vs Navigation Specialty

AOW Navigation dive vs Navigation Specialty

How much do they differ?? I realize that Nav. Spec. is more "in depth", but...

maybe, just getting a book and studing it on my own would be a better idea (plus it's cheaper ).

Any thoughts??

khel

My advice would be to take the course. Navigation is more involved then what you get in an AOW course. It will cost a little bit but if your instructor is well qualified it will be worth it. In my AOW natural navigation was never even mentioned. Now I used that much more then compas navigation. Just my opinion and yes I am an instructor but not a navigation specialty instructor. After the ok sign, where is the damn boat is my most used sign!

Joe

Getting lost on a wreck is not all that likely if you have any kind of situational awareness at all (and are not narc'd out of your mind!) Just remember what feature of the boat the anchor is on/near, and you're cool.

On a reef, however, its a bit of a different matter.

In any event getting lost underwater is not a good thing. Around here at least there is a good chance of a ripping surface current - often, they are flatly unswimmable. The bottom can be completely devoid of ANY current, but at 10-15' you pick up a real mask-ripper.

The problem is that without a reference you don't KNOW when you pass the current zone - you might sense it with the thermocline, but if you're drifting there is a good chance you won't realize you're in a 1-knot+ current, because you're moving at the same speed - no relative motion.

This is big trouble; you ascend in "free water", and while on your safety stop you drift 1/2 mile away! Eeeeek!

Since you do not KNOW where the "breakpoint" is between the current and no current, you can't do the stop a bit deeper if necessary. Without a referance.....

Now if you have an upline you can use, then you can work around this. But even so, being unable to get back to the anchor line - if the boat is anchored - or the buoy line if you're live-boating - is very un-good.

If you can't be reasonably certain of getting back and there is a significant current then you need to think CAREFULLY about what you (and the surface support!) will do if you get lost. This is NOT so simple as "have a safety sausage."

Two weeks ago we had 2+ knot currents on one of our dive sites. It was flatly unswimmable on the surface - mask-ripping speeds. You had to pull yourself from the back of the boat to the anchor line via a granny line, and then pull yourself down the first 15' or so until the current went away - then you made your decent normally.

If anyone had been unable to find the line (and this was a reef dive!) for the ascent they would have been in a world of hurt. With a half-dozen people in the water, you CANNOT pull anchor and go get someone drifting off - that is simply not an option until everyone else is back on board. While I can sound a "recall" (engine revs) to the divers in the water, it takes time for them to ascend, do their safety stops, and reboard. During that time you're off to Cuba!

Give CAREFUL consideration to this if you dive where there are surface currents in particular.... although it applies to bottom currents as well.

I wasn't that impressed with Nav class. BUT, that's because I used to teach land nav in the army. After teaching people how to navigate at night with only a compass through 12 points of different azimuths over a 6 km course (not just a 100 meeter box pattern), water nav is nothing.
I suggest reading the book, find a boy scout and have him explain the finer points of intersection, resection, back azimuths, saddles, draws, etc. Once you understand the basics of land nav, you'll have no problems.

First, depends on the Nav class;

Second, depends on your needs;

Second factor first: Karl is right, above, that there are different categories of need. In some cases, like where he's diving, currents and potential hazards make navigation reasonably important, but not terribly complex.

Its important to be able to do what is needed, but what is needed is pretty straightforward in terms of skills and abilities.

In some cases, however, like research diving or uw site mapping, or wreck hunting, navigation needs can become more complex. It isn't all back azimuths and resections, or squares and rectangles.

Which brings us to the first factor...

Not all Nav courses are equal.

Much of what you learn depends on your instructor, and the complexity of the Nav course. They vary considerably. Underwater navigation is less like land nav and more like nautical or aviation nav. Attempting to traverse a distance in a current may, like sailing, require that the diver hold a specific compass bearing that "crabs into the wind", or heads somewhat into the current to achieve a true azimuth along a desired heading.

There used to be a device called, if I recall correctly (and I will be corrected, no doubt, if not), a "Scuba Sextant". It was a round protractor that allowed the diver to plot and execute uw navigation involving vectors, intercepts, and more complex navigational requirements. Obviously, most divers do not have these sorts of needs. My point is that if you do have, for some reason, need for a complex uw Nav course, they do exist. You've got to find them.

If you are interested in developing skills and abilities with underwater navigation, I suspect you may have better luck taking a good course rather than consulting a self-help manual or a boyscout.

Doc

Genesis once bubbled...
With a half-dozen people in the water, you CANNOT pull anchor and go get someone drifting off - that is simply not an option until everyone else is back on board.

Click to expand...

TIP:

Make sure you have a buoy you can tie to the anchor line. If you then notice someone drifting you can tie the buoy to the top of the anchor line and release the boat.

This allows the boat to drift off and pick up those who lost the line as well as leaving the reference line for those who don't lose it.

DO NOT LET ANYONE DIVE WHO DOES NOT HAVE AN SMB AND WHISTLE !!!

You can then also allow surfacing divers back on the boat in a drift situation - they leave the line and get back on the drifting boat (both travelling at same speed) which can be alot less stressful.

Motor back and the pick up the anchor line.

(note I deliberately avoided the complexity of retrieving an anchor in current which often involves grabbing the line and motoring against the current to remove the snag without running over the rope with your engine !!! Make sure you know how to do this too)

Thanks guys! I don't think that the places I dive for the moment require advanced havigation skills, but it's better to be ready, than sorry

Doc Intrepid once bubbled...
I suspect you may have better luck taking a good course rather than consulting a self-help manual or a boyscout.

Doc

Click to expand...

And what about the official course book (PADI or Naui)? Would it be enough?

As for boyscouts, I think I can find my way in a forest better then many of them Plus, I'm more interested in underwater navigation specifics...


khel

Make sure you have a buoy you can tie to the anchor line. If you then notice someone drifting you can tie the buoy to the top of the anchor line and release the boat.

This allows the boat to drift off and pick up those who lost the line as well as leaving the reference line for those who don't lose it.

Click to expand...

That works for small boats, but does not for large ones - like my Hatt.

The bitter end of my anchor line is attached (firmly attached!) below decks. There is no good way for me to release it and attach it to a buoy, nor would this work well without a VERY large buoy (lest the line pull it below the water!)

DO NOT LET ANYONE DIVE WHO DOES NOT HAVE AN SMB AND WHISTLE !!!

Click to expand...

Yes, everyone must have surface signalling devices. But even with them you can still be in serious trouble; a "Dive Alert" is the best option for a noisemaker, as its REALLY loud, but it only works if you have gas in your tank.

When the current is like this I give fair warning that the site is far more advanced than usual, and if you're not comfortable with being able to get back you might want to consider a suntan rather than a dose of nitrogen.....

If you are serious about learning the material and skills, take the course.

There is much to it in terms of using charts, plotting magnetic courses, counting kick cycles, triangulation, and natural navigation techniques. Then there is the requirement to work in buddy teams with one doing the depth monitoring while the other maintains heading. Also, drawing underwater maps. It's the in-water hands-on training with an instructor who can provide tips and guidance that really puts it in your head. (On the other hand, you need to make sure the course covers what you want to learn BEFORE you take it! Apparently many are not particularly in-depth. )

How much could you have learned from reading the PADI or NAUI Open Water Certification Manual in the absence of the pool or confined water sessions? Did your instructor contribute anything meaningful to your learning process? Reading about mask removal and replacement or neutral bouyancy is one thing. Doing it is another.

You asked for recommendations. If you want to learn uw nav, I recommend you take the course.

Doc

Rather than a dedicated AOW course, SSI AOW requires the completion of four specialties and 24 open water dives. (Most shops also run a "course" that is comprised of four specialties) The Navigation specialty can be one of the four. So, if you choose to go with SSI, you can take the Navigation specialty, and over time take three others that interest you. Once you've completed four specialties and have 24 or more logged open water dives you can apply to SSI and they will issue you the AOW diver card.
E.