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Kimusubi
11-21-2008, 23:11
I recently purchased a compass, and I want to learn how to use it to its full potential. The main reason for this is, 1) I need to get my buddy from point A to point B to point C, then back to point A without getting lost next weekend, and 2) we're going to be doing some night dives next weekend where this will come very handy. I know how to do the straight forward and back compass use, but my question is how to go from one straight point to another, make a turn, and go to another point, make another turn, and eventually backtrack my way. I know there is a way to adjust the compass on each turn, but unfortunately I don't know how. I tried googling it, but nothing came up with great detail. The compass I use is Suunto SK7 which has a spot to read your position on the side. If anyone has any suggestions or links to anywhere that will explain the techniques in detail, I would really apprecaite it. Thank you all for your help in advance.

FishFood
11-21-2008, 23:19
Here's a VERY good, and detailed guide:

Compass Parts (http://www.compassdude.com/compass-description.shtml)

Be sure to check out the sections (on the left):

Headings
Orienting a Map
Triangulation
Route Planning
Pacing

EDIT:

Also, dont forget you can practice these skill above water too!

cutter77
11-22-2008, 03:29
Get a towel, put it over your head. Hold your compass level and practice taking headings and returning on reciprocals..use a notepad to jot them on.

(I did this out in the pasture so I wouldn't run into anything and no one saw me but the horses.)

maverick
11-22-2008, 08:42
Take a navigation course 2 clear up any questions.

awap
11-22-2008, 08:45
Out and back is fairly easy. You know (or select) the direction for out ande then back is just the opposite direction (+/-180). To do a triangle, you need to know the azimuths between each of the three points. Do you k now those azimuths?

Gumby
11-22-2008, 09:35
Take a navigation course 2 clear up any questions.

Your deep, intellectual insight intrigues me. I wish to subscribe to your newsletter. :smiley24:

Here is a great read to help you get an understanding of the fundamentals: SCUBA (http://www.geocities.com/k_o_dionysus/scuba/uw_nav/index.html)

Two things I highly recommend... PRACTICE on land first! Do not think that just because you read how to use a compass that you will remember how when underwater. Practice, Practice, Practice!

If you have a slate, I strongly recommend writing down your headings and bearings when you are first getting started with U/W navigation.

Both of these ideas are for one reason.... to help you minimize any task loading. Add in a buddy to monitor depth and air consumption, and you'll off load even more tasks.

crosseyed95
11-22-2008, 09:40
Take a navigation course 2 clear up any questions.

Your deep, intellectual insight intrigues me. I wish to subscribe to your newsletter. :smiley24:

Here is a great read to help you get an understanding of the fundamentals: SCUBA (http://www.geocities.com/k_o_dionysus/scuba/uw_nav/index.html)

Two things I highly recommend... PRACTICE on land first! Do not think that just because you read how to use a compass that you will remember how when underwater. Practice, Practice, Practice!

If you have a slate, I strongly recommend writing down your headings and bearings when you are first getting started with U/W navigation.

Both of these ideas are for one reason.... to help you minimize any task loading. Add in a buddy to monitor depth and air consumption, and you'll off load even more tasks.

These are VERY good suggestions.

James1010
11-22-2008, 10:21
There are some things you might want to learn such as what type of training are you going to do. In the woods if you have points you are going to you need to get a pace count and so fourth. I don't feel like typing because it will be way to long but here is a basic site to go to. Compass - how to use one (http://www.compassdude.com/)
If you are doing it underwater it's different. You can't shoot an azimuth.

monant
11-22-2008, 10:46
If I anticipate a lot of turns I use a SCUBA sextant. They are easy to use and get the job done very well. Google it and you should be able to find where to purchase one.

http://www.instructor-training.com/osimg/sext2.jpg

Kimusubi
11-22-2008, 15:07
Yeah I've been reading compass dude's website. A lot of interesting stuff. I haven't gotten a chance to read the whole thing, but I get a hang of it of how it works. I'm definitely going to start practicing it on land before we go to California, and I'll eventually take the class for underwater navigation. The only problem with taking it now is the time constraint.

Let me get this straight though:

If I start at point A, and I go directly in a straight line to point B for lets say 10 kick cycles, then I go 70 degrees North North-West for 10 kick cycles to point C, and then I take a direct 90 degree south to point C for another 10 kick cycles. Now to get back, I would do ten kick cycles to 20 degrees North-North East, then take another 10 kick cycles at 70 degrees South-South East, and finally take ten kick cycles directly south.

I used no compass for this, simply because I just wanted to get a feel for how it worked. In retrospect, my directions don't really make sense, but if anyone can clear it up for me, I'd really appreciate it.

Here is a LOVELY paint image of how I went through with it. Excuse my poor paint skills and my absolutely terrible scaling.

http://c2.ac-images.myspacecdn.com/images02/27/l_4bb308a2294645cca7589b8f4841f775.jpg

awap
11-22-2008, 17:01
Yeah I've been reading compass dude's website. A lot of interesting stuff. I haven't gotten a chance to read the whole thing, but I get a hang of it of how it works. I'm definitely going to start practicing it on land before we go to California, and I'll eventually take the class for underwater navigation. The only problem with taking it now is the time constraint.

Let me get this straight though:

If I start at point A, and I go directly in a straight line to point B for lets say 10 kick cycles, then I go 70 degrees North North-West for 10 kick cycles to point C, and then I take a direct 90 degree south to point C for another 10 kick cycles. Now to get back, I would do ten kick cycles to 20 degrees North-North East, then take another 10 kick cycles at 70 degrees South-South East, and finally take ten kick cycles directly south.

I used no compass for this, simply because I just wanted to get a feel for how it worked. In retrospect, my directions don't really make sense, but if anyone can clear it up for me, I'd really appreciate it.

Here is a LOVELY paint image of how I went through with it. Excuse my poor paint skills and my absolutely terrible scaling.

http://c2.ac-images.myspacecdn.com/images02/27/l_4bb308a2294645cca7589b8f4841f775.jpg

You need to work out the azimuths from the turn angles. I never have been very good a counting kick cycles. I prefer working with transit times and my slow. steady constant swim pace.

So, it looks like your x-axis is the east-west axis. So you intend to travel at 0 degrees from A to B. Then you plan to turn to a heading of 340 degrees to point C. Then you plan to turn to 250 degrees and swim to point D. So the back azimuths are 70 degrees from D to C; 160 degrees from C to B; and 180 degrees from B to A. If the points A, B, C, & D are readily recognizable features, it should not be too difficult as long as you don't have to compensate for currents.

cummings66
11-25-2008, 17:45
I did google the scuba sextant because I couldn't fathom how a sextant which works by reference to celestial bodies could work under water and it turns out it's really a Nav-finder by Padi. Now what I find interesting about it is it makes life easy for the diver because you have a form of sorts to record your dive directions on.

To use it simply requires you know your kick cycle distance and pay constant attention to your heading. Pretty slick and I appreciate the posting talking about a scuba sextant because I would have never considered a way to do it with a tool.

I've done it the hard way by making notes on a slate, pretty common but I like the automated way, well, sort of automated. Thanks for the posting, I learned something new today and now I'm happy.

navyhmc
11-25-2008, 20:09
One other thing. While doing a compass course: Look Around! Don't keep your eyes glues to the compass. Unless you're in 1' vis muck, you'll miss stuff and if you notice things ahead of you and to the sides of you if you get off course, you have other things to follow other than the complass. Always have a back-up plan.

sea princess
12-10-2008, 23:46
One other thing. While doing a compass course: Look Around! Don't keep your eyes glues to the compass. Unless you're in 1' vis muck, you'll miss stuff and if you notice things ahead of you and to the sides of you if you get off course, you have other things to follow other than the complass. Always have a back-up plan.
This is great advice..I am in the middle of doing my navagation class at the lake and i found myself looking at just the compass at first and missing out on what was around me and the natural navagation points. I was quite excited i did get back to my starting point which for me is a miracle. I suck at having a sense of direction so learning to use a compass is a long overdue skill for me to learn.

bubbletrubble
12-11-2008, 00:40
@Kimusubi: To elaborate on what awap has posted, whenever you refer to a direction in compass terms (heading in degrees), the standard convention is that zero degrees is due north, 90 degrees is east, 180 degrees is south, and 270 degrees is west -- no matter what your position is. The number that you read through the "window" on your SK-7 compass is the heading.

Compass navigation isn't rocket science. I really wouldn't suggest taking a formal course in it (unless the course is offered for free). It's nothing more than tracking distance (kick cycles), direction (degree heading), and using simple geometry to figure out where to go next. As someone else pointed out, compensating for currents can make navigation a little more challenging.

I completely agree that you should exploit the existence of natural and man-made navigational landmarks. For example, on my local shore dives, one swims perpendicular to the ripples in the sand to get back to shore. When I'm at a new site on a dive boat, I tend to use more natural landmarks, like a peculiar rocky reef formation, to help find my way back to the boat. YMMV.

When taking headings with your compass, constantly check that the compass is level by tilting it around. It should be moving freely within the oil. I've seen instructors leading their classes astray by following "stuck" compass needles. :-) You'll be happy to know that the SK-7, unlike some other compasses, can tolerate a fair amount of tilt.

Have fun on your dive...

MSilvia
12-11-2008, 10:47
Pretty slick and I appreciate the posting talking about a scuba sextant because I would have never considered a way to do it with a tool.

I've done it the hard way by making notes on a slate, pretty common but I like the automated way, well, sort of automated. Thanks for the posting, I learned something new today and now I'm happy.
Likewise! That's a pretty cool idea, and something I'd never heard of before.

ThunderAce
01-01-2010, 18:07
One other thing. While doing a compass course: Look Around! Don't keep your eyes glues to the compass. Unless you're in 1' vis muck, you'll miss stuff and if you notice things ahead of you and to the sides of you if you get off course, you have other things to follow other than the complass. Always have a back-up plan.
This is great advice..I am in the middle of doing my navagation class at the lake and i found myself looking at just the compass at first and missing out on what was around me and the natural navagation points. I was quite excited i did get back to my starting point which for me is a miracle. I suck at having a sense of direction so learning to use a compass is a long overdue skill for me to learn.


Natural Navigation is a wonderful skill to develop, but even while using a compass it is a good idea to look around. Several reasons pop into my little brain....

#1 look ahead so you don't swim into that rock, wall, diver, whale, etc...

#2 look behind every now and then so you can see what to look for on the return trip.

#3 look around so keep track of your dive buddy.

#4 look at your gauges! If you are concentrating only on your compass it is really easy to change depth radically. Especially watch your SPG so you have some air. I have my compass mounted on the same housing as my pressure gauge so I constantly look from one to the other.

And practice. Get a buddy to grab a compass and navigate a course thru your yard or around town. Have him write down the headings and steps travelled, then you try to end up exactly where he did.

Most of all, have fun!

inventor
01-01-2010, 18:24
When taking headings with your compass, constantly check that the compass is level by tilting it around. It should be moving freely within the oil. I've seen instructors leading their classes astray by following "stuck" compass needles. :-) You'll be happy to know that the SK-7, unlike some other compasses, can tolerate a fair amount of tilt.

Have fun on your dive...

YES! I was going to post that this is a common mistake for me. I hold the compass down, at an angle, and it sticks. Also, whoever posted the 'look behind you every once in awhile' has it right. Whenever I'm being led somewhere, and I pass through an opening, I turn around and look, so I know what it looks like on my way back. And look again after a couple of seconds.:smiley20:

(To clarify, the openings refers to land. But I also look behind while diving.)

Soonerwink
01-02-2010, 17:46
Your compass is an invaluable little tool and you should now how to use it! It gets you to Point A and then back again, (a reciprocal course).

It's great for navigating a multi-route course around a dive site, where multiple leg-routes are involved, and at the end of the dive to confirm where your exit point is and swim towards it!

Underwater Compasses come in different styles with the most common being added to your gauge console, along with your depth gauge, and psi gauge.
Another form is a wrist compass which is on straps like a watch.
And another form is attached to a retractor.
And the newest on the market is a digital compass made into your computer, I know nothing about these, have never tried one.

BASIC COMPONENTS:
A dive compass has 4 components that every diver should know and how to use them:
1) The Lubber Line
2) The North Arrow
3) A Rotating Bezel with reference marks (looks like a watch dial)
4) Degree Calibration Marks

FIRST OFF IS THE LUBBER LINE: The lubber line is what marks the direction that the diver is going in.
The compass is always held so that the lubber line is perpendicular to the diver's shoulders out in front of you and parallel to your line of site.

THE MOST BASIC COMPONENT OF THE COMPASS: THE NORTH ARROW:
The North arrow on every compass always points to the Magnetic North.
If you move the compass clockwise or counterclockwise (backwards) the arrow will always point to the Magnetic North!!

THE COMPASS IS EQUIPPED WITH A ROTATING BEZEL:
The bezel contains 2 reference marks on it, the primary mark (0 degrees) the primary is usually 2 marks together and the reciprocal mark (180 degrees) N and S.
These 2 primary marks give the diver a reference when traveling out to a point in a straight line, and the reciprocal mark brings you back to the starting point.

THE DEGREE CALIBRATION MARKS Dive compasses also have the degree calibration marks and these marks run from 0 (zero) degrees to 360 degrees.
You use these marks when doing a multi-leg underwater route or when going from one known point to another.
The degree markings are similar in all brands of dive compasses but, some calibration marks are displayed in different ways.
Some compasses have the marks on the outer face only, some have them on the outer and inner face, and some even have them on a really convenient side window for seeing them from the side.

PRETTY SIMPLE TO USE: No matter what kind of course you're diving the compass is always held out in front of your body and slightly below eye level.
The lubber line is then positioned perpendicular to your shoulders and pointed STRAIGHT ahead in the direction that you want to go.
But to function properly it has to be on a level plain.

NAVIGATING USING A COMPASS:
To do this you must first establish a compass course.
To do this you point the lubber line, (the straight line inside your compass) in the direction you want to go.
Then you rotate your bezel until the primary reference marks are directly over the N arrow.
You usually establish your course from just before entering the water from a dive boat, or from the beach if you're doing a shore dive.
Or you can even do it from a boat's anchor line after you've descended.
To keep the course underwater you simply swim forward, keeping the point of N arrow between the 2 reference points.
If you go off course the arrow will move to one side or the other of the reference points.
To correct this and get back on track, you just swim left or right until the N arrow is once again between the 2 reference marks.
As long as the arrow is between the marks YOU'RE ON COURSE!!

To get back to the starting point just reverse your course, slowly turn your body until the point of the N arrow is situated directly in line with the reciprocal reference mark and follow it back.

You can also navigate a square pattern by adding or subtracting 90 from your calibration number depending if you are turning left or right. Remember to count your fin kicks to do a better square pattern.

OTHER CONSIDERATIONS WHEN USING A COMPASS:
You'll quickly learn that other things affect your compass use.

CURRENT, is one of them, a strong cross current makes it difficult to keep on a straight compass course. Even if you keep the N arrow where it should be you may find yourself drifting off your intended course due to the current pushing you sideways.
Always be aware of this and compensate to make up for this current. Also large metal objects like a bus can affect your compass readings. Even the metal in swimming pools will affect your readings as well as some quarries such as Oronogo.

I hope this helps and doesn’t confuse you more. If I left something out let me know.

DIVE SAFE EVERYBODY!!
Todd