Navigation
Last updated February 5, 2013
Lessen Plan Title: Navigation
Trainer Name:
Training Time: 30 minutes
Prerequisites:
 Reading: Chapter 3
 Modules: Nautical terms (?)
Audience: West African fisheries observers
Equipment: (include associated file names (e.g. ppt))
 AV: LCD projector, computer, laser pointer,
 Software: MS Powerpoint, MS Word,
 Files: v1.2_LP_navigation.doc, v1.2_navigation.ppt
 Gear & other props: pencil, calculator; blow up globe, charts, radio microphones, GPS
 Activity: Charts; Homework: Conversations & distances
Detailed text associated with ppt presentation) Note: any text in italics is additional information for the
trainer and is not intended to be part of the lesson plan. Answers to the questions asked are in orange
text.
Slide 1 - Introduction
Navigation is the act of determining a vessel’s position, ascertaining speed and directing the course of a ship
by using charts and electronic aids. While the observer not responsible for navigation, there are some terms
and basic equipment you need to be familiar with in order to complete your duties as an observer.
Slide 2 - Objectives: By the end of this module, you will be able to
 Define navigation
 Discuss the differences between latitude and longitude
 Convert latitude & longitude from one format to another
 List 3 navigation aids and explain their functions
 Choose the appropriate radio for various situations
 Identify 4 important features on a chart
Slide 3 – using blow-up globe as teaching aid
The earth is a sphere that rotates around an imaginary line running through the north & south poles.
*The equator is a circle around the earth that is perpendicular to this rotational axis and splits the earth
into a northern and southern section. Running parallel to the equator are additional circles around the
earth that get smaller as you go north & south. Parallels or lines of latitude are measured in units of
degrees. How many degrees are between the equator and the north pole? [90°] Does anyone know how
degrees are determined?
Slide 4 – latitude is a measure of the angle between the plane of the equator and lines projected from the
center of the Earth to a point on the earth’s surface. In the orange section of this cutout diagram, the angle to
the point on the earth’s surface is 30 degrees north of the equator which is 0 degrees.
Page 1 of 7
Navigation
Last updated February 5, 2013
Does anyone know the latitude of Monrovia? [6° 18’48” N ] Libreville [0° 23’24” N ] Other training
location..
Slide 5 – Lines of longitude, or meridians, circle the globe intersecting each pole. The longitudinal
equivalent of the equator is called the prime meridian (0°) which splits the globe into east and west sections.
There are 180º of longitude in each direction.
Slide 6 – The degrees of longitude are determined in a similar manner as latitude. In the yellow section of the
cutout diagram, the angle to the point on the earth’s surface is 90 degrees to the west of the prime meridian.
Does anyone know the longitude of Libreville? [09° 27’ 0” E ] Monrovia? [10° 48’5” W ]
When the two systems are combined, you get coordinates that define a specific point on the planet.
Slide 7 – Degrees can be split into smaller units called minutes of arc (these minutes are somewhat
analogous to time). Each degree consists of 60 minutes of arc. Each minute of arc consists of 60 seconds (60
seconds =1 minute).
*In terms of distance, 1 nautical mile equals 1,852 meters or slightly more than one statutory mile on land
(1.15 miles).
*Mariners measure speed in a unit called knots. One knot equals about 1 nmi per hour.
Slide 8 – There are a few navigational terms that may be useful.
A chart is the nautical term for a map. A chart is a projection of the earth’s sphere from three
dimensions (like the globe) onto a flat surface ( 2 dimensions). Traditionally vessels carry a set of paper
charts (as shown) but in recent history electronic charts are the primary chart used and the paper charts
are used if the electronics fail.
Slide 9 – CHART ACTIVITY. Teresa will work with instructors prior to presentation to set up.
Slides 10- 14 – currently hidden. If activity in slide 9 not possible, familiarize observers with terms on
these slides
Slide 15– Bearing is the direction (measured in degrees) of an object expressed either as a true bearing or
as a bearing relative to the heading of the boat
Course – direction vessel is being steered
Current is the horizontal movement of water and can have an effect on a vessels course or on the
effectiveness of the fishing gear.
Slide 16 – A variety of equipment is used for navigation.
A compass is an instrument for determining directions by means of a freely rotating magnetized needle that
indicates magnetic north.
Page 2 of 7
Navigation
Last updated February 5, 2013
Slide 17 – GPS, or Global Positioning System, plotters or more elaborate interactive nautical charts are the
norm in industrial fisheries today.
Slide 18 – GPS readings can be output in multiple formats. You should be aware of the format when
recording position data from the vessel’s GPS unit. The three formats are: degrees, minutes, seconds;
degrees, decimal minutes; and decimal degrees. [point out the symbols used for degrees, minute & seconds]
If you need to convert Degrees, minutes, seconds to degrees, decimal minutes, divide seconds by 60 and add
to minutes. In the example, 30/60 = .5 which is added to minutes to get 25.5 minutes
If you need to convert Degrees, decimal minutes to decimal degrees, divide the fraction of minutes by 60 and
add onto the degrees.
If you need to convert Decimal degrees to degrees, decimal minutes, you would multiply the decimal value
by 60. In the example above you would multiply 0.425 by 60 to get 25.5 minutes.
Does this make sense? If not, work thru a few more examples on the board.
Slide 19 – Radar uses an electromagnetic wave to detect solid objects day or night. They may also be used to
help find gear by detecting radar deflectors attached to the gear. The radar can estimate distance to a given
object and determine the speed an object is moving.
Slide 20 – The vessel shown here has a radar deflector on its main mast and also on the fishing gear.
Slide 21 – Sonars & echosounders both use sound waves to determine bottom depth and objects in the water
column.
Slide 22 – Communicating by phone is not as common at sea but there are a couple of options. There will be
times when vessels will be operating close enough to land to access cellular phone service. Some of your
ships will also have satellite service for a phone or email system which is very expensive. You will likely
not be able to use this unless there is an emergency.
Slide 23– The most common form of communication will be by radio. There are two types of radios used by
fishing vessels - VHF and SSB.
Slide 24 – VHF stands for Very High Frequency. Channel 16 is the International Distress Safety and Calling
Channel. The transmission distance of VHF is a function of antennae heights and in general, is slightly more
than the distance one can see.
Slide 25 – Radio communications over distances beyond twenty miles (35 km), will require you to use a high
frequency radio referred to as Single Side Band or SSB. Signal quality is inferior to VHF and susceptible to
slight atmospheric shifts but the SSB is more reliable for medium and long distances. All ship SSB radios
must be capable of operating on 2182 KHz (the International Distress Safety and Calling Frequency) and at
least two other frequencies.
Slide 26 – Radios are different from telephones in that they cannot transmit and receive simultaneously.
Keep in mind that people on other ships can also hear your conversations. Speak directly into the
Page 3 of 7
Navigation
Last updated February 5, 2013
microphone; speaking loudly, slowly, and distinctly. Upon completing a transmission you must sign off by
identifying the vessel and using the words "clear" or "out."
When hailing another station on an emergency channel, you must switch to a working channel after initial
contact is established. Finally, keep transmissions short and concise.
Slide 27 – General calling procedures
1. Make sure radio is on and appropriate channel is selected. Listen momentarily to make sure the channel is
not in use.
2. Background static from the radio speaker can be reduced with the squelch control. However, too much
squelch can drown out incoming transmissions. Adjust the squelch so that a small amount of static is barely
audible or to the point where the static first stops. The captain will likely give you specific instructions for
the radio on board.
3. If there is no one talking on that channel, begin by depressing the button on the microphone and calling the
name of the vessel or other station you are trying to contact three times, followed by your vessel name and
call sign and the channel you are broadcasting on since most ships and stations listen simultaneously to
several channels.
Examples:
“DG Péche, DG Péche, DG Péche. this is the Happy Fisher TJAE (tango, Juliet, alpha, echo) on
channel 16 over."
“FMC, FMC, FMC. this is the Happy Fisher TJAE(tango, Juliet, alpha, echo) on channel 16 over."
4. If there is no initial response to your call, wait a couple minutes before repeating the call. If there is no
reply, repeat at two-minute intervals up to three times, after which you should sign off and wait at least 15
minutes before making another attempt.
5. If contact is established, you must switch to a working channel to continue your transmission.
6. When you have temporarily finished talking and are ready to listen, say "over," and release the button on
the microphone. When the other party is ready to listen they will also say "over."
7. After you have completed your conversation, end with the vessel name, call sign, and the word "out" to
signal the end of your transmission. Example: ".... This is the Happy Fisher TJAE out."
We will discuss distress calls in much more detail during the safety module.
Slide 28 – Summary or summary questions: Review the main objectives
 How is navigation defined?
a) The act of determining a vessel’s position
b) Ascertaining speed
c) Directing the course of a ship by using charts and electronic aids
d) None of the above
e) All of the above
Slide 29 – Summary
 If a vessel has an 8 foot draft, could it be fishing in the vicinity of (A)? [no] what about (B) and
(C)? [yes, yes]
Page 4 of 7
Navigation
Last updated February 5, 2013
Slide 30 – Summary
 Describe latitude and longitude?
 How many minutes are in a degree of latitude? [60] How about longitude? [60]
 List 3 navigation aids and explain their functions [charts, GPS, radar, depth sounder, compass,
etc..)
 Which radio would you use to call a vessel that you can see? [VHF]
 Which radio would you use to call the observer program 100 nmi away? [SSB or HF]
 Homework – conversion practice
Page 5 of 7
Navigation
Last updated February 5, 2013
Navigation – Homework
Name:
Complete the problems/conversions below given the following:
1 degree = 60 minutes (‘)
1 minute = 60 seconds (“)
1 nmi = 1.15 miles = 1,852 meters
1 knot = 1 nmi / hour
1 degree of latitude ≈ 60 nautical miles
1. Convert N 06°49’23” to degrees, decimal minutes ___________________
2. Convert S 01.293° to degrees, decimal minutes ___________________
3. Convert E 24°17’01” to decimal degrees ______________________________
4. How many meters are in 268 nmi? _______________________
5. What is the approximate distance (nmi) between the following latitudes: N 06°49’43” and N
06°29’13”?
_______________________
6. How long would it take a vessel traveling 7.5 knots to travel 35 nmi? _____________________
Page 6 of 7
Navigation
Last updated February 5, 2013
Navigation – Homework [ANSWERS]
Name:
Complete the problems/conversions below given the following:
1 degree = 60 minutes (‘)
1 minute = 60 seconds (“)
1 nmi = 1.15 miles = 1,852 meters
1 knot = 1 nmi / hour
1 degree of latitude ≈ 60 nautical miles
1. Convert N 06°49’23” to degrees, decimal minutes ___ N 06°49.3833’__________
23 seconds ÷ 60 seconds/minute = 0.383333 minutes
2. Convert S 01.293° to degrees, decimal minutes ____ S 01° 17.58’ _______
0.293° * 60 minutes / degree = 17.58 minutes
3. Convert E 24°17’01” to decimal degrees _________ E 24.2836°________________
Step 1: 1 second ÷ 60 seconds/minute = 0.0167 minutes
Step 2: 17.0167 minutes ÷ 60 minutes / degree = 0.2836 degrees
4. How many meters are in 268 nmi? _____496,336 meters _______
1,852 meters = X meters
1 nmi
268 nmi
X = 1,852 * 268 = 496,336 meters
5. What is the approximate distance (nmi) between the following latitudes: N 06°49’43” and N
06°29’13”?
N 06°49’43”
- N 06°29’13”
20’30” or 20.5 minutes which equals 20.5 nmi
6. How long would it take a vessel traveling 7.5 knots to travel 35 nmi (round to nearest hundredth
hour)? [hint: speed = distance/time ; V=d/t]
7.5 knots = 7.5 nmi/hr
1 hour
7.5 nmi
=
Page 7 of 7
X hours
35 nmi
X = 35 nmi ÷ 7.5 nmi/hr = 4.666667 hrs or 4.67
hrs ( 4 hrs, 40 min )