lee chamberlain, aaus topographic mapsfiles.meetup.com/381057/navigation 101.pdf · 24,000 inches...
TRANSCRIPT
Navigation 101
Lee Chamberlain, AAUS
Objective: The objective of this seminar is to familiarize the student with a basic understanding of map,
compass and GPS uses. In our discussion you will learn how to read and understand a topographic map,
nautical chart and to have a basic working knowledge of how to navigate combining map reading and a
magnetic compass. As well we will discuss the GPS system and how to apply that knowledge with the
GPS handheld device.
Topographic Maps and Nautical Charts:
Topographic Maps:
Typical mapping of a topographic map.
Before we begin to discuss the symbols we need to understand that a map is a graphic representation of
the surface of the earth drawn to a scale. The map that we will be using is the 7.5 topographic maps,
with a scale of 1:24,000 inches. What this means is that for every one (1) inch on the map it represents
24,000 inches on the map or about 2, 0000 feet on the ground. Topographic maps show many features
not associated with either highway maps or navigational charts. Topographic maps detail many land
features and as well show Elevation and Relief. Meaning that in reviewing a topographic map you are
getting a perspective as to the type of terrain features such as hills and valleys building location,
railroads and highways, improved roads and unimproved dirt roads. Features such as wetlands, power
lines and pipelines. As well in the areas outside the map drawing you will find vital information that you
need to understand the use of your map both with compass and gps.
http://egsc.usgs.gov/isb/pubs/booklets/symbols/topomapsymbols.pdf
Prior to the advent of the GPS system maps were drawn to scale from field survey using a device called a
transit, it was in the use of this device, actual field verification was made from a starting point that was
marked with a Benchmark. A Benchmark is a plate or monument placed at a specific point on the ground
and anchored for a reference. It is not uncommon to find a notation on a map such as BM186 or other
number. The number accompanying the notation is the “spot elevation” of the site. Other elevations are
shown simply by numbers. The most common identification used in mapping prior to the GPS/WGS
system was known as NAD27, this means North American Datum and the year 1927, over time field
verifications were done to verify and note changes to both the usage and topography of the area.
Usually done from development. Most maps in the United States were made by the United States
Geologic Survey or the United States Army Corps of Engineers. Some locales and state offices made their
own maps from these.
References known as the Marginal Information (the area outside of the map itself) detail many facts, for
instance the year of publication usually found directly below the left corner of the map, the scale which
is usually printed in Feet, Miles, and Meters. The formula for the map whether it was WGS or UTM, WGS
is an abbreviation for the World Geodetic System, UTM stands for Universal Transverse Mercator. We
will discuss these briefly in discussions. But the important aspect here is to understand that this
information is contained in the marginal information is very relevant to the accuracy of your map.
Usually in the center of the map or on one side slightly off center you will see a small diagram this
diagram usually is in the form of a line drawing with a letter value and a star. This is called the
“Declination Diagram” it states the difference between the THREE NORTHS, yes 3 norths. MN stands for
Magnetic or Compass North as it is also known, the STAR stands for TRUE north, and finally the GN
stands for Grid North. The difference here is that the earth’s magnetic north and true north have a
different location. Grid north is the defined difference in publication by survey. As a general rule the
main concern of resolving the values is the difference between Magnetic (aka Compass) North and True
North. In general the compass (magnetic deviation) east of a line of magnetic north is written as west
declination so as to compensate for the variation, on the declination diagram it is shown whether your
declination is east or west. An example for Richmond, Virginia the declination is approximately 10
degrees west, so to find True North you would add 10 degrees to your bearing (direction of travel) to
plot a true course, most simply use the degrees magnetic few ever plot their course in bearings true.
So as an example, if I were travelling a course of 180 degrees magnetic and wanted to plot it on a map
as true I would add 10 degrees to my bearing of 180 +10= 190. This we will discuss more in field bearings
and compass use. But the main feature here to understand is the difference between the three norths
and you map.
Latitude/Longitude vs. UTM on maps. Along all four sides of a 7.5 topo you will find notations by a
series of numbers, if the map is based as UTM these are the positions on the Mercator system. These
are usually a series of numbers these numbers usually are in 6 to 8 digit series. On the base and top of
the map as in the numbers are read from the longitudinal line to the right and from the side up. An
explanation of these is that they place a location within 100 meters when transposed as six digits, and
within 10 meters (39.37’) if in the 8 digit series.
As well Latitude and Longitude lines are read similarly so if you were looking at a map lat/long numbers
are written in Degrees, Minutes and Seconds There is a twist here as everything west of 0 degrees
longitude is written as minus (-) and everything east of that line is written as plus (+). For instance
37d28’21” N -077d16’13”W the 37 means that it’s at a line of position 37 degrees 28 minutes 21
seconds on a line of position above the equator ( 0 degrees latitude) and west of a line of position of the
Prime Meridian.
The point being that the differences in east or west can be regarded as insignificant when you orient the
map to the compass, which in many ways is the way to navigate with your map lined up with magnetic
north. In the field, orienting the map to magnetic works preferably better and the results are often more
accurate as to getting from point “A” to point “B”.
Nautical Charts:
The primary difference between a Nautical Chart and a Topographic Map is that one is land based and
the other is designed with maritime navigation in mind. Benchmarks that exist on Topographic Maps are
replaced on Nautical Charts by indicators for Buoys and lights which for our intent and purpose is the
adopted equivalent of the Benchmark. Buoys mark the channels the lanes in which recommended travel
afloat and required for maritime commercial travel.
A guide to understanding all the symbols and terminology can be downloaded off the NOAA.Gov site for
free and is recommended. As well Chart books can be downloaded from the NOAA Site.
Nautical Charts were created to give mariners the maximum information available based upon reports
of hydrographic data, reported shipwrecks, surveys conducted by sonar and other devices. To the sailor
the knowledge of depth, shoals, reefs, prominent underwater obstructions are a critical concern. Bear in
mind that depth measurements are taken at mean low tide, and do not reflect high tide depths. As well
only significant land based features are usually added to nautical charts and as well monthly there is a
“Notice to Mariners” added to the NOAA Coastal Site by NOAA each month.
Nautical charts differ as well as to scaling and as to intent, so combining studies along coast areas if
there is a plan to venture inland from shore after making beach. Scales on Nautical Charts are often
larger as the expanse of water and area covered on a typical chart are larger than say a 7.5 topo map.
Significantly detail is greater to water and its immediate area, for instance, Channels, and depths are
often indicated by numbers as opposed to the solid brown line of a contour map as in the case of Topos.
Nautical Charts as well usually have a compass rose in circles with the outer ring being True North and
the inner ring being Magnetic North. Charts often have two or three such compass rings so that in
plotting a course the plotting device (scale or Weems) can be applied to develop course line plans. On
some but not all highways (routes on water) are pre-plotted as to bearing to mark, in other words
location and direction of one buoy as well as distance. These such as the one on the Potomac River aid
tugboats and other commercial vessels in staying within channels which are clearly identified on the
charts. Obstructions and shoals are outline and as well often named as in the case of many shoal areas
are identified by name. Lines on a maritime chart are graduated in Lat/Long designations as opposed to
UTMs on Topographic Maps. Bear in mind this is an overview so a lengthy discussion here of reading
maritime charts is suspended.
The key to remembering in Navigational charts designed for water is to what end the individual is
planning use time on water and Launch ( or put in points as in the case of sea kayaking). Port or docking
(take out as in kayaking).
Nautical Charts give as well an advantage in that where channels and known currents exist these are so
identified, as well military areas where live firing is held and special features are often noted directly on
the chart. Not all military areas have Range Boats, (Boats used to stop or clear boat traffic)
The nautical chart is a vital tool when working in water areas and as well a clear understanding of the
preparation is indication on the chart with the contributing agencies such as National Ocean Service,
Coastal and Geodetic Survey, Corps of Engineers, Defense Mapping Agency, NASA, State and Local
Agencies all contribute to the data contained on Nautical Charts. Modern Nautical Charts (Government
and Commercially prepared charts also contain additional data, GPS waypoint data.)
For the sake of this orientation we will examine Nautical Charts and do a minor plot using the
Rappahannock River Chart.
The Compass
The magnetic compass as we know it evolved from a simple block of wood with a magnetized needle
placed on top of it. Compasses come in all shapes and sizes have a variety of quality or the lack thereof.
The sole purpose of the compass is Direction, in the case of most compasses of quality the dial is broken
down to as little as two degrees of azimuth (directional angle) in small tick marks and marked in 10
degree numerical values from 0/360 to 90 to 180 to 270 to 0/360. Think of if you will that you are
standing in a circle and a compass gives you 360 possible paths. Each path with a different result.
Unlike the GPS the compass does not normally work on batteries and should be your mainstay as it will
die when the batteries are gone.
Compasses as I said come in a host of sizes and types. For instance a land surveyor or builder may use a
compass that is broken into quads where divisions are in 90 degree increments but the translation of the
bearings are in the four cardinal quadrants N degrees E , S degrees E , S degrees W, N degrees W. I
mention this only in passing.
Most modern day compasses are designed on a standard platform of 360 degrees. Specialty compasses
such as those for Orienteering, Use on Boats, Each with a defined use, but in essence still a compass. A
brief description is included here in imagery.
Top left Deck Mount Compass, Top Right Hand Bearing Compass, below left typical Handheld Compasses
The compass parts are as follows:
The base , the manner in which the device is attached, Military type compasses have a fixed base and
the dial turns on a pivot on the base, to which the Bezel (degrees and mils ) is affixed.
Bezel which is the usually moveable ring with degrees so marked
Direction of Travel or Lubing Line: Both indicate the sight taken when the compass is read.
The NEEDLE this is the little jewel that points to Magnetic North, usually pained RED.
The base of a compass can be very simple or very, very elaborate with scales and rulers. The most
important part is the Needle ACCURATELY pointing NORTH. I fit doesn’t then all those little frills are
WORTHLESS. Compasses mounted in things like hunting knives, walking staffs should always be
considered suspect. Think about this a knife is usually made out of steel, steel is magnetic. By the way
Rambo’s trail was marked.
As well things like Cell phones, flashlights or any metal object should never be near or under a compass
when you are using it. (Yes you can use a flashlight to read a compass at night but a luminous dial works
a lot better.)(Luminous means it glows in the dark). Anything with a battery emits an EMF (electro -
magnetic field).
Common Compass Terms (or how to impress your friends with a few words)
Azimuth: means nothing more than direction
Bearing: The read degree range of the number appearing on the compass ring (bezel)
Line of Travel line: It’s the line indicated under the ring that points in the direction you are heading.
Back Azimuth/Back Bearing: Simply put you are traveling in reverse by 180 degrees, as opposed to
reorienting your compass you are simply turning your compass base to where North Indicating Arrow is
now at the base of the North Arrow Alignment Gauge outline on the base of your compass.
Formula for a back bearing:
If the direction of travel bearing (read degrees) is Less than 180 degrees ADD 180 degrees to that
bearing to obtain you’re back bearing. Example: Bearing of 70 degrees original course, add 180 degrees
to obtain the back bearing of 250 degrees, the exact reverse of your original course direction.
70+180=250
Now if the reading ( degrees indicated in your original direction of travel is Greater than 180 degrees,
then you SUBTRACT 180 degrees from that number, Conversely it will be the exact reverse of your
original direction. Example bearing of 233 degrees original course, minus (subtracting) 180 degrees gives
a bearing of 53 degrees as your new heading.
233-180=53
Its simple there is no complex formula here
Using a compass, as I said a compass gives you 360 possible paths to travel barring obstructions,
mountains or oceans. So that you will understand when you look at a map and read degrees. A compass
like a clock is broken down in increments, Four Cardinal Points, North, East, South and West. These can
be divided between any two points and you get North East, South East, South West, North West, These
points can be broken down as well further, North North East, East North East, East South East, South
South East, South South West, West South West , West North West, North, North West. For use with a
compass an understanding of the cardinal points of a compass are very relevant. The same as bearings
some people travel by what is termed “Ded Reckoning” also known as Deductive Reckoning. So an
understanding of bearing as opposed to a good guess as to direction is very relevant. Orienteering which
was and is still quite popular in Europe is based on the combining of both of these forms of compass
travel. With that said we will move on.
Using a compass alone:
Compass navigation is a very rewarding experience, one that builds confidence. In the days of the
ancients, compasses were truly the only reliable indicator position, until reaching a known point.
Travelling by bearings, in other words compass alone is a lost art. With the advent of charts, maps and
GPS in a matter of minutes we can plot a route and follow it to a point on the map, or for that matter a
satellite reference point.
Knowing the approximate of a place, the length of your step, or the amounts of time it takes to walk or
paddle a distance can very well determine a destination arrival. Knowing how to operate your compass
when traversing obstructions and recovering your bearing is essential to navigation by compass or map
and compass. Hence we will discuss how to navigate around obstructions using the rules of 90 in field
practices.
Setting a bearing, most compasses have a “Bearing Set” in other words you line up the compass over the
direction of travel line at the mark and that bearing will be the one you follow. “Survival” compasses do
not usually have the luxury of a base. They usually point basic directions and never really well. Hence for
land navigation a good compass should have a good base plate, a freely moving needle, but as well
should be dampened at Manufacture so that it does not swing wildly. The bearing set should be easily
moved but not as well rotate so loosely that it cannot be set in one bearing line and hold same. And the
direction of travel indicator that at a glance you can determine if you are on or off course. In our
discussion of travel by sea kayak we will discuss the values of aiming off using a lubing line set. Cross
country travel by compass makes this an imperative.
Once you have determined the direction you need to go by bearing. Line up the North Indicating arrow
with the indicator guide, the outlined arrow inside the compass face. Hold the Compass at waist level
look down and then sight up across some distance to a landmark easily recognized as you travel. Once
you reach this point, look at your compass and repeat the process .It’s that simple. Following the bearing
you have set you can easily return to the point from which you started by simply holding the compass in
reverse or using the “Back Azimuth/Bearing Method”. If you changed direction during the course of your
traverse across country make a note to yourself as to how long ago the change was made or at some
really distinguishable reference point. The important thing to remember is to always line up the north
indicating arrow within the guide; this has to become second nature. A compass error of a few degrees
from failing to do this can equate to as much as 1000 yards at one mile, so always check the guide and
arrow alignment.
In the field we will discuss and practice the rules of 90, and 120.
Map and Compass:
Okay once you learn to shoot bearings, walk a course it’s time to put it in practice. You can align any
topo map with magnetic north and go from there. Remember what I said earlier about the declination
diagram. 3 North’s, you can plot most of your routes and by compass headings using the alignment
method at home. Place your map on a flat level surface such as a kitchen table, Orient the map by
turning your compass with the North Indicating arrow and the North South Arrow on the map; you can
do this in the field as well on flat ground. Now using a ruler plot your course, and then move your
compass next to the ruler and turn the bezel till the North south indicator is realigned and the bearing is
revealed over the direction of travel line. This is called rough plotting. Write the information down on a
piece of paper or in a notebook, now move on to your next point aligning the ruler with the two points,
again move your compass alongside of the ruler and realign the North indicating arrow and North guide
on the compass face. That is your second bearing once you have read the bearing indicated on the face
of the compass.
Once you reach your destination regardless of changes you will be able to find your way back to your
starting point. To some this may sound complex at first but it is very easy and simple and works
extremely well. But you ,must keep your map stationary when doing the plots, as chances are you will
reorient the map and in so doing change the values of the bearing. Commonly called plot error.
Compass and Map or Chart with a kayak:
In our research we travel primarily by sea kayak, there are a number of variables that exist in water
travel that do not exist on dry land. In areas where there is a strong current or for that matter a weak
one we employ a method called aiming off. Aiming off is simply plot an original course line and then aim
off an extra 15-30 degrees (30 in the case of an extreme current); other considerations are winds and
tides. Over water distance perception is deceptive, on a clear day a point of land can look only to be
about a mile away when in fact it can be six miles (6) miles away
as illustrated here. Sea conditions, tides and currents all play a role in navigation as well as following the
bearing taken from a chart or map. This can become especially true when navigation is practiced on the
Chesapeake Bay. Currents on the Chesapeake as well as the mouth of the Chesapeake can be
treacherous. The worst current on the Chesapeake is at Annapolis Maryland near the narrows of the
Route 50 Bridge. When Navigating, if you have a choice, avoid paddling narrows across to the other side
it’s here, where you will learn very quickly the value of “Aiming Off”.
To make a long story short, I was with a group of friends and we decided to paddle from Cape Henry to
Cape Charles. It’s a hefty paddle we plotted our course set for corrections and as well carried a GPS. We
knew two key factors were going to come into play, one the changing of the tide as we would be
paddling well over six hours, and the other is the outfall current of the Chesapeake . We made jokes as
the day wore on and an unpredicted thunderstorm came up, suddenly made our jokes not so funny
anymore. We raged against the storm for about 30 minutes as it passed and found ourselves over a half
mile off course. Had we assumed our course was still on track we would have found ourselves heading
to the Gulf Stream? Made the landing at Cape Charles two and half hours late but still had we not had
the opportunity to field check after the storm our next stop after the Gulf Stream could have easily been
Scotland 3000 miles away. Our saving grace was we decided to “aim off “into the Chesapeake as the tide
was running out we needed to insure we were not heading out to sea in the Atlantic. I personally use a
Nexus 85 deck compass mounted on neoprene to my life lines, now my deck bag. Two of the other boats
lost their compasses when overspray washed their decks. Even though we had planned everything down
the wire, the winds of the thunder storm took us towards the Atlantic. Our return trip was a little saner
as we tracked the Bay Bridge till we got back.
Sea Kayak navigation whether it be across a river, such as the Potomac at Colonial beach or Annapolis,
or Cape Henry to Cape Charles requires practice, developing skill sets and coping mechanisms that
convince you to ALWAYS TRUST YOUR COMPASS. A paddler’s logic sometimes is to debate the accuracy
but in traversing from one beach to a distant shore out of sight of land to another the compass is the
governor of the day. The GPS we used that day was a Magellan Pioneer Vintage 1998 with two screens
one for position and the other that gave us speed, bearing, distance, and heading. By locating our
position we were able with the aid of the GPS to make the course correction to the waypoint we had
established from obtaining latitude/longitude from the charts. Hence when we made landfall at Cape
Charles we joked about everything from wondering what time it was as to whether or not the whiskey
would be that much different (which it is) as opposed to who would have the funniest kneecaps in a kilt.
The object here is that we lived to joke about a turn in the weather and as well make safe landfall before
dark. It was in part to a good GPS and as well trusting the equipment we were using as an aid to
navigation.
The GPS
There are many types of GPS devices on the market, some old established and some Johnny come lately.
A GPS works on the theory of location by triangulation. Depending on the type of device, the altitude of
the satellites, the availability of a clear sky, the battery condition these devices work well. Simple GPS
systems have limited capability. Some offer only two screens Position and movement and others offer
everything down to the kitchen sink.
Over the years I have used a host of these devices, for a lot of tasks from marking the position of a
shipwreck I was surveying to a fun day in the woods, hunting or hiking. Travel by GPS is more or less a
given these days as we use them in our day to day commutes. As well some GPS units are called cross
over GPS as they go from vehicle to trail and usually have a built in battery with no ability to interchange
batteries.
For most travel off route a good GPS should have the following features, it should be lightweight have a
replacement power source (batteries) carry spares. It should be rated as a WAAS or better system,
waterproof (IPX 7 means submersible to 1 meter 39.37 inches for one half hour)
Start Up:
Most GPS units are pre-programmed to locate a specific point, as well make sure your GPS is set for your
time zone. The base map in several units is basically a highway map of the US or area of use design. Note
make sure your unit is setup for the United States/North America.
Screens:
With each unit available today it’s impossible to say that all are the same. For example a simple setup
like my old reliable Magellan Pioneer had two screens; the Magellan Triton 500 that I am testing has a
host of screens in addition resources within those that make this a sweet little unit. I often use another
manufacturer Garmin and have one of the Garmin GPS III Plus models with basic base map, or as I
sometimes call it the Guess map. It still gives accurate location lat/long and does a lot of things the older
unit I have do not. Until its demise I often carried a little Etrex GPS which was a basic unit that offered
position and tracking screen.
To say the least there have been three really reliable manufacturers that I trust these being Garmin,
Lowrance, and Magellan. There are others out there and I have to say they may or may not be equal to
these three. GPS devices are like compasses, kayaks or for those matter flavors of coffee. Much a matter
of personal preference and taste as to use and functionality. So that is a debate I am going to forego.
One of the odds and ends devices I have is what I call a spotting GPS that allows me to connect to my
computer it’s a Pharos GPS500 and as well another device that connects to my handheld Dell Axim50 its
one of those C card things. Still in all they perform a function. As does a mobile GPS point A to point B.
A good GPS now incorporates a SD Card where you can download maps from many commercial sites, I
primarily use Topo Explorer for my personal navigation and on the boat I use the system incorporated
with my sonar unit.
Using a GPS is like having a personal tour guide in some respects, the function I like best within two
systems the Magellan Triton Series 400 and 500 is the electronic mapping capability . It’s nice to have a
map immediately at hand. Garmin in its GPS units such as the Garmin Map60 and GPS 76 also have the
same capability. Both of these units perform well. I think I would shy away from the one device does all,
by that meaning radio/gps. If I need a radio I think my preference there would be a standalone radio.
Besides GMRS and FMRS are devices not supposed to be used on water, and as well my handheld
marine band 5 watt set fulfills my needs there. The GMRS/FMRS systems boast a 5 mile mile range; my
portables however range out to 12 miles further on GMRS. The point being I am not interested in device
that will consume batteries that I need for navigation. As well there are marine band radios that also
give a fix for location.
The integral use of a GPS for Route planning is undeniable you can preprogram the device with
established waypoints and alarms to let you know when you reach a way point thus eliminating doubt.
Navigating with GPS by kayak is feasible provided it can be either deck mounted or carried on a lanyard
to eliminate loss (hmmm maybe center mounted on a paddle, nah that is extreme).
Position finding can be set in UTM, Degrees Minutes Seconds , Decimal Degrees, Degrees Decimal
Minutes Seconds, as well as the base can be NAD27, 83, or WGS84. Distances on a GPS can be in meters,
miles, statute or nautical ( hikers, backpackers, motorist usually use Statute Miles where Sailors use
nautical miles, kayakers on the other hand use both, depending on locale). Inland it’s better to use
statute miles than nautical miles especially in times of emergency and reporting same via cell phone to
local law enforcement or rescue agencies. There is a substantial difference in Statute vs. Nautical miles
and can mean a significant difference in rescue when reported as most Police , Fire, Rescue
organizations ask what is a location close to and if you measure the distance in Nautical miles inland
rescue may not show up at all
Paths or trails can be recorded and will appear as overlays; as well Points can be later recovered.
Combined with mapping features the GPS is both map and compass that is very battery dependent so
the user should always carry two extra sets of batteries in a watertight container. (Ziploc bag,
Waterproof Box)
In our field exercise we will practice using the GPS as a means of finding position, and routes to and from
other positions.
Since most of this orientation is aimed at land navigation I am going to include three good reference
books on the subject.
These are :
Be Expert With Map and Compass
Kayak Navigation by David Burch
Chapman’s Piloting
GPS for Dummies
These manuals will aid in your furthering your knowledge of this skill set.
Recommended for general knowledge development:
Sea Kayaking by Derek Hutchinson
Survival with Style by Bradford Angier
The Wilderness Outdoorsman Emergency Handbook
Practical Exercise:
Locating certain landmarks by examination, identifying Grid Coordinates using UTM
Map Orientation by compass
Compass Exercise:
Rules of 90
Rules of 120
Compass Mini Course
Cross Country Compass course
GPS Navigation
Geocache (land based)
Geocache (water based)
During the practical exercise we will combine map, compass, GPS uses to be coherent and cohesive.
Other Devices:
Often when I trek I am asked what if your cell phone does not work, there are several different types of
devices that can be used but these are active devices that will send a signal to an emergency service. A
device that I carry is called “SPOT”
Satellite Personal Tracker.
This device offers some unique capabilities, it can be used to send an email that says you are ok, as well
it can also notify for both nonemergency help as well as emergency services. Too it can be used to send
a signal to a special website where friends and family can track your progress as you move down a trail
or waterway. Lightweight, waterproof and it floats powered by two “AA” lithium batteries it’s a sound
investment when traveling in the backcountry or on water areas remote from home or near shore. As an
emergency beacon the device transmits your location on the 911 feature. Devices that were of use were
the old 121.5 EPIRB ( Electronic Position Indicating Radio Beacon) these were replaced with a satellite
capable beacon simply known as the ELT ( Electronic Locator Transmitter) these operate in the 462 band
and transmit to the National Rescue Coordination Center, which dispatches a message to the regional or
local rescue coordination center. Once activated this device is assumed to be in a transmit mode of life
threatening emergency and services will be dispatched. False calls can result in fines, cost of the
apparatus or agency responding and their costs. The advantage of the “SPOT” over this is that it can
send a signal where people can see where you are, and as well let them know you are okay, send a
signal for non emergency help, like flat and no jack, or send help with the 911 feature. SPOT has been
attributed for sending help in some pretty harried events including airplane crash, Avalanche, and ship
sinking. Paddling locally or on open water it gives me a somewhat comfort level I have not had before.
EPIRBS, I will say that the old 121.5 Epirbs required up to 6 full hours before it was considered an
emergency due to false signals. Which is why the 121.5 devices were phased out this year.
SPOT puts a rescue service at your fingertips and as well lets those you know you are safe when used for
email or tracking. The unit costs about 150 and the service fee is another annual 150 well worth the
peace of mind. (Before you ask, no I do not sell them they are available at sporting goods dealers).
The best locating device you can have is the knowledge to use the equipment and the applications it was
designed for, practice both in the field and at home. Keep the equipment in a good state of repair and
condition.
No Batteries Required……………………………..
GEOCACHING
Geocaching is a relatively young event that hones skills to use GPS; it’s more like an Orienteering turned
treasure hunt. A Cache is hidden and the locations are given in latitude longitude coordinates, places like
public parks, state forests, national forests and parks recreational areas. Often GPS is the only device
needed for finding the cache marking it on the GPS and moving on to the next cache site.
Other sites may require the ability to use a compass if the GPS is not so equipped for descriptions and
directions are left in one cache box that lead to another.
Tools for Geocaching: Compass GPS, Listing of sites and topo map
Geocaching is one of those sports (for lack of a better word) that in addition to the obvious benefit of
fresh air skills for navigation by both device and compass can be honed.
Geocache methods usually involve locating the listing, whether it be a cache or benchmark and
navigating from a point of beginning to the site and return or to other sites. The advantage is learning
skills in not only navigation but in observation, cross country travel.
Equipment for this even can be as simple as a handheld GPS a pair of comfortable shoes and appropriate
clothing for the weather, a notebook for recording site information, a walking stick as opposed to
rummaging through a bush or under a log.
Recommended but not required but handy, Walking stick, a day pack with water, raingear (poncho)
camera just in case you want to document the site with an image. A snack and a flashlight.
Arriving at the starting point, turn it on, its here that you make your first waypoint on your GPS, that
way you can reverse your route and return safely to your car. (Most sites are located in Parks or state
lands or national parks or forests.)
You enter if you have not already the coordinates of the cache site, and in to the woods you go. You can
conserve your batteries by entering the site in and taking a compass bearing read off the gps and
continue cross country by compass checking your GPS as you go. Or by GPS alone.
You get close to the site as identified by the GPS, here you pay less attention to the GPS and use your
skills of observation, looking for the cache. Most Cache containers have been painted to camo so as to
make them appear less likely to be found by a casual passerby. They are never buried, can be put under
leaves, a log or hidden in a hollow of tree, get creative.
You find the cache, sign the log, and if you take one of the treasures meant to be taken, you must leave
something of equal or better value. A sideline to this if you are hiking through carry a trash bag and
consider picking up any trash around the site and packing it out. Cache in Trash out.
At this point if it’s a multiple site you move to the next site, sign the log and move on or return to your
vehicle. It’s that simple and you have had the fun of maybe exploring some site you never would have
thought about.
Some cache sites are historic in other words you sign a log, observe the marker or historical references
around you, a great way to learn history. Others will sometimes have hints placed in one cache box with
a compass bearing and number of steps to go to reach the site.
There are many organizations that promote this however geocaching.com is one site where you can get
information for sites without actually being a paid member as a basic membership is free. Not
promoting an organization just the information on site. It’s an individual decision.