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From: Craig Jungers <crjungers_at_gmail.com> subject: [Paddlewise] Paddling on Instruments - part two Date: Sun, 23 Sep 2007 18:32:08 -0700 · This archive was generated by hypermail 2.4.0 : Thu Aug 21 2025 - 16:33:46 PDT

The most basic instrument for your kayak is the compass. If you are on a
trip and manage to stumble into an area of low visibility the compass should
be viewed as your primary navigational system with your GPS as a secondary.
This is because the compass needs no batteries and will operate correctly
the entire time you are at sea.

A quick recap of terms:

1. A compass does not tell you where you are. It only points the way to
magnetic North. But you can use this to determine headings to other points.

2. There are 360 degrees in a circle. A compass typically numbers these in a
clockwise direction from magnetic North (zero degrees) through East (90
degrees), South (180 degrees), West (270 degrees) and back to North 360/0
degrees. The numbers 360 and 0 both refer to North.

3. Your compass does not point to the North Pole. It points to the North
Magnetic Pole which is displaced from the North Pole. It is constantly on
the move and has, in fact, switched poles (to become the South Magnetic
Pole) several times in the geographic past.

4. Magnetic declination (more commonly known as magnetic variation) is the
measurement of the difference in degrees between true north and magnetic
north. It can also refer to localized magnetic disturbances.

5. Deviation generally refers to the errors in the compass itself whether
caused by factors inside the compass or issues like large bits of metal
placed in close proximity to the compass.

6. The corollary to #5 is: Don't place items containing ferrous metals
within about 2 feet of the compass. Put them in the stern. And don't rely on
"stainless steel pots" being truly non-magnetic. Test them with a magnet
first. There is stainless and then there is *stainless*.

7. In order to navigate your kayak in poor visibility you have to know what
the compass will read (the correct heading) for the course you need to stay
on.

Okay... all of this is relatively easy to understand. But it all relies on a
compass which you have corrected. What if you have a temporary compass; one
that you might hook onto your boat using bungee cords. How can you make sure
that it's going to be useful?

For a temporarily mounted compass the mounting needs to be accurate and
repeatable. In other words, for your compass to be useful you should be able
to put it back in exactly the same orientation as when you made your
correction card. This could be as simple as using a Sharpie to mark the
compass and deck or as complex as designing a compass platform. Just
remember that as long as it's in the same position every time the deviation
will remain the same (except for placing large pieces of ferrous metal near
it).

Of course, your compass will be useless unless you have some idea of what
heading to steer using it. If you've paid little or no attention to it up
until the weather socked in and have no courses plotted on a chart or
notepad, then you're still going to be in potential trouble. So if weather
closes in you should take a few quick sights. First of all you should note
down the heading you are paddling. Then you should turn around and see if
you can get a quick reading on any nearby landmarks or, especially,
potential escape routes to a safe landing place.

What you might have done back at your last camp was to make a quick plan and
note down courses and distances and then turn those distances into estimated
time to paddle. This way, if weather closes in and you are caught out, you
have some idea how long you should be paddling to the next turn point.

What is the difference between a "course" and a "heading"? A course is the
magnetic or true bearing between two places; often drawn in as a line on a
map. A heading is the compass (or, on a ship, the gyro) reading that will
keep you on the course. Note that the course may be identical to the
heading. But often it's not and even more often on a small boat. Remember
your compass correction course and the notation that read, "FOR 090 STEER
096"? The course has to be corrected for compass deviation before you have
your heading. You can write this in on the chart if you like. Be sure you
have a way to distinguish one from the other.

Other factors that will affect the 'heading" are current set and wind drift.
So, for instance, if you are supposed to steer 096 to head 090 and want to
go 090 you could find current and wind affecting that heading. You may have
to steer 100 to stay on course 090.

How do you lay a course? Well it's simple enough if you have a couple of
tools. Airplane pilots use a small protractor which you lay along a course
with the protractor over a longitude line. You can then read the true
heading for that course from the protractor. You must then add or subtract
variation (look at the compass rose on the chart) and then correct for
deviation. Make a note of that course for reference later. I like to also
calculate the reciprocal heading for that course (180 degrees difference)
just in case I need to go back. You could also carry a parallel rules by
which you can transfer a course up to the compass rose on the chart and
simply read off the magnetic heading. But doing either of these while you
are in your cockpit on the ocean are difficult at best. It's advisable to do
it while you're on the beach before you launch.

If you have a GPS, of course, all this is greatly simplified. As long as you
have sufficient battery power a modern GPS will do much of this work for
you. You can create a complete trip plan in advance using waypoints saved
into the GPS in advance. In fact, some of the fun of planning a trip can be
deciding where to place the waypoints for maximum safety and paddling
efficiency. This way you could conceivably leave the GPS turned off and only
turn it on when you want a position fix; like when the weather closes in.
You'd have a reference for how far you need to paddle to the next waypoint,
a heading, and a reciprocal course for turning back.

Having a GPS can work both ways; it can make planning easier (and even fun)
or it can lure you into not bothering to plan at all. After all, if you just
leave the GPS on you could just turn around and follow the dots (electric
bread crumbs left as a trail) back to your last beach. Or, if your GPS is
sufficiently sophisticated you could just use it for all your navigational
needs and follow the blinky cursor to wherever it is you're going. This is
actually a viable solution for short trips and if you have a pretty good
idea of where you're going and the line you need to follow to get there. But
it's advisable to do at least some planning before you leave even if it's
putting a waypoint in for your destination.

On trips with an older (non mapping) GPS I would just use the device to give
me a course and only turn it back on every hour or so to correct my course
for drift and current set. Modern GPS units are much easier on battery life
but the downside is that their maps are not as detailed as one might like;
at least not off the shelf. For instance, the Wasp Islets between Crane
Island and San Juan Island in Washington State do not appear on the standard
maps of the units I looked at in 2006. And these are pretty big rocks
(several with houses)!

So, assuming you have corrected your compass and understand how to apply the
corrections, here is a brief set of rules to keep you on course if you are
beset by fog

If you have only a compass:

1. Check your compass heading before the visibility gets too bad.

2. Cross check for escape routes.

3. If you are in a seaway try to average the compass readings to stay on
course.

4. Do not fixate on the compass but simply refer to it from time to time.
Keep your eyes moving to make sure you don't paddle into danger.

5. Be aware of time-to-paddle so that you don't overrun your destination in
the poor visiblity and paddle into possible danger beyond.

If you have a GPS:

1. Set a waypoint for your current location and set a route to your
destination (or turn point) waypoint.

2. Once you are on course for your next waypoint you can turn the GPS off
(to conserve batteries) and steer the proper compass heading.

3. Turn the GPS on every hour or so to get a fix and check for drift and
current set. If your GPS is a mapping unit with good charts then you can
check for any dangers close to your position.

4. Alter your heading as appropriate to get back on course.

5. If you have lots of battery power you can use the GPS to keep you on
course but steer mostly using the compass.

6. Do not fixate on either the GPS or compass but, rather, move your vision
across both in a patter that also scans the ocean ahead of you for danger.

Um... so what do you do if you have neither a compass nor a GPS? Well,
actually, there are ways to stay on course here too.

On land we are used to changeable winds. It's not uncommon for a land wind
to box the compass as the land warms and cools. On the ocean it's much less
common for winds to be variable. Barring cold winds tumbling out of fjords
and steep valleyes (and it's always wise to be careful of these) once the
wind begins to blow on the ocean it pretty much blows that direction for a
while.

So the first thing to do when beset by fog and without a compass or GPS is
to note the direction of the wind and the swell. It's worth mentioning here
that the two are not likely to be from the same direction. This can actually
be an asset in poor visiblity as the two directions can form a way to
triangulate your course. Keep the wind and the swell on the same points as
they were when the fog set in and try to keep your most steady pace. You do
have some idea of how fast that is, don't you? Use this to determine when
you think you are near to your destination and when you've covered that
distance you can carefully work your way in closer to shore.

One other plus to a sea fog is that very often the sun is still clearly seen
when it's too foggy to see ahead or to the sides. So you can navigate by the
sun. Just remember that as the day progresses the sun will appear to move
across the sky.

In north America and northern Europe during the summer the sun moves from
northeast at sunrise through south at mid-day to northwest just before
sunset.

In south America, s. Africa, Australia and New Zealand in the summer the sun
moves from southeast at sunrise through north at mid-day to southwest just
before sunset.

If you want to continue paddling when fog and poor visibility can be
expected then it only makes good sense to be prepared to deal with it in
terms of both equipment and psychology.

I have a paddling friend who always prepares the same way regardless of the
paddle conditions. She wears a drysuit and carries safety and first aid gear
for both a paddle on Puget Sound (water temperature of 50F) and a paddle on
Lake Washington (water temperature of 75F) because that way she knows she is
always prepared and has left nothing out. She has a permanently mounted
compass that she has corrected. She carries a GPS but she doesn't rely upon
it. Sometimes it's a pain in the butt, I agree. And although I'm doing
better, I do not always follow her example. But if she and I are paddling
together and there is a problem, I'm pretty sure she'll be ready for it.

So I stick close to her because if I am not the best prepared person on any
trip, I want to be right next to the paddler who is.

Craig Jungers
Royal City, WA
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