Navigation is a field of study that focuses on the process of
monitoring and controlling the movement of a craft or vehicle from one
place to another. The field of navigation includes four general
categories: land navigation, marine navigation, aeronautic navigation,
and space navigation.
It is also the term of art used for the specialized knowledge used by
navigators to perform navigation tasks. All navigational techniques
involve locating the navigator's position compared to known locations
Navigation, in a broader sense, can refer to any skill or study that
involves the determination of position and direction. In this
sense, navigation includes orienteering and pedestrian navigation.
3 Basic concepts
4 Modern technique
4.1 Mental navigation checks
4.3 Celestial navigation
4.3.1 Marine chronometer
4.3.2 The marine sextant
4.4 Inertial navigation
4.5 Electronic navigation
4.5.2 Radar navigation
4.5.3 Smartphone navigation
5.1 Ships and similar vessels
5.1.1 Day's work in navigation
5.1.2 Passage planning
5.2 Land navigation
6 Integrated bridge systems
7 See also
10 External links
This section needs expansion. You can help by adding to it. (August
Further information: History of navigation
See also: History of geodesy
In the European medieval period, navigation was considered part of the
set of seven mechanical arts, none of which were used for long voyages
across open ocean.
Polynesian navigation is probably the earliest form
of open ocean navigation, it was based on memory and observation
recorded on scientific instruments like the Marshall Islands Stick
Charts of Ocean Swells. Early
Pacific Polynesians used the motion of
stars, weather, the position of certain wildlife species, or the size
of waves to find the path from one island to another.
Maritime navigation using scientific instruments such as the mariner's
astrolabe first occurred in the Mediterranean during the Middle Ages.
Although land astrolabes were invented in the
Hellenistic period and
existed in classical antiquity and the Islamic Golden Age, the oldest
record of a sea astrolabe is that of Majorcan astronomer Ramon Llull
dating from 1295. The perfecting of this navigation instrument is
attributed to Portuguese navigators during early Portuguese
discoveries in the Age of Discovery. The earliest known
description of how to make and use a sea astrolabe comes from Spanish
cosmographer Martín Cortés de Albacar's Arte de Navegar (The Art of
Navigation) published in 1551, based on the principle of the
archipendulum used in constructing the Egyptian pyramids.
Open-seas navigation using the astrolabe and the compass started
Age of Discovery
Age of Discovery in the 15th century. The Portuguese began
systematically exploring the
Atlantic coast of
Africa from 1418, under
the sponsorship of Prince Henry. In 1488
Bartolomeu Dias reached the
Indian Ocean by this route. In 1492 the Spanish monarchs funded
Christopher Columbus's expedition to sail west to reach the
crossing the Atlantic, which resulted in the Discovery of America. In
1498, a Portuguese expedition commanded by
Vasco da Gama
Vasco da Gama reached India
by sailing around Africa, opening up direct trade with Asia. Soon, the
Portuguese sailed further eastward, to the Spice Islands in 1512,
China one year later.
The first circumnavigation of the earth was completed in 1522 with the
Magellan-Elcano expedition, a Spanish voyage of discovery led by
Ferdinand Magellan and completed by Spanish
Juan Sebastián Elcano
Juan Sebastián Elcano after the former's death in the
Philippines in 1521. The fleet of seven ships sailed from Sanlúcar de
Barrameda in Southern
Spain in 1519, crossed the
Atlantic Ocean and
after several stopovers rounded the southern tip of South America.
Some ships were lost, but the remaining fleet continued across the
Pacific making a number of discoveries including
Guam and the
Philippines. By then, only two galleons were left from the original
seven. The Victoria led by Elcano sailed across the
Indian Ocean and
north along the coast of Africa, to finally arrive in
Spain in 1522,
three years after its departure. The Trinidad sailed east from the
Philippines, trying to find a maritime path back to the Americas, but
was unsuccessful. The eastward route across the Pacific, also known as
the tornaviaje (return trip) was only discovered forty years later,
when Spanish cosmographer
Andrés de Urdaneta
Andrés de Urdaneta sailed from the
Philippines, north to parallel 39°, and hit the eastward Kuroshio
Current which took its galleon across the Pacific. He arrived in
Acapulco on October 8, 1565.
The term stems from the 1530s, from
Latin navigationem (nom.
navigatio), from navigatus, pp. of navigare "to sail, sail over, go by
sea, steer a ship," from navis "ship" and the root of agere "to
Map of Earth
Lines of longitude appear vertical with varying curvature in this
projection, but are actually halves of great ellipses, with identical
radii at a given latitude.
Lines of latitude appear horizontal with varying curvature in this
projection; but are actually circular with different radii. All
locations with a given latitude are collectively referred to as a
circle of latitude.
The equator divides the planet into a
Northern Hemisphere and a
Southern Hemisphere, and has a latitude of 0°.
Further information: Latitude
Roughly, the latitude of a place on
Earth is its angular distance
north or south of the equator.
Latitude is usually expressed in
degrees (marked with °) ranging from 0° at the
Equator to 90° at
the North and South poles. The latitude of the
North Pole is 90°
N, and the latitude of the
South Pole is 90° S. Mariners
calculated latitude in the
Northern Hemisphere by sighting the North
Polaris with a sextant and using sight reduction tables to
correct for height of eye and atmospheric refraction. The height of
Polaris in degrees above the horizon is the latitude of the observer,
within a degree or so.
Further information: Longitude
Similar to latitude, the longitude of a place on
Earth is the angular
distance east or west of the prime meridian or Greenwich meridian.
Longitude is usually expressed in degrees (marked with °) ranging
from 0° at the
Greenwich meridian to 180° east and west. Sydney, for
example, has a longitude of about 151° east.
New York City
New York City has a
longitude of 74° west. For most of history, mariners struggled to
Longitude can be calculated if the precise time
of a sighting is known. Lacking that, one can use a sextant to take a
lunar distance (also called the lunar observation, or "lunar" for
short) that, with a nautical almanac, can be used to calculate the
time at zero longitude (see Greenwich Mean Time). Reliable marine
chronometers were unavailable until the late 18th century and not
affordable until the 19th century. For about a hundred
years, from about 1767 until about 1850, mariners lacking a
chronometer used the method of lunar distances to determine Greenwich
time to find their longitude. A mariner with a chronometer could check
its reading using a lunar determination of Greenwich time.
Further information: Rhumb Line
In navigation, a rhumb line (or loxodrome) is a line crossing all
meridians of longitude at the same angle, i.e. a path derived from a
defined initial bearing. That is, upon taking an initial bearing, one
proceeds along the same bearing, without changing the direction as
measured relative to true or magnetic north.
Most modern navigation relies primarily on positions determined
electronically by receivers collecting information from satellites.
Most other modern techniques rely on crossing lines of position or
LOP. A line of position can refer to two different things, either
a line on a chart or a line between the observer and an object in real
life. A bearing is a measure of the direction to an object. If
the navigator measures the direction in real life, the angle can then
be drawn on a nautical chart and the navigator will be on that line on
In addition to bearings, navigators also often measure distances to
objects. On the chart, a distance produces a circle or arc of
position. Circles, arcs, and hyperbolae of positions are often
referred to as lines of position.
If the navigator draws two lines of position, and they intersect he
must be at that position. A fix is the intersection of two or more
If only one line of position is available, this may be evaluated
Dead reckoning position to establish an estimated
Lines (or circles) of position can be derived from a variety of
celestial observation (a short segment of the circle of equal
altitude, but generally represented as a line),
terrestrial range (natural or man made) when two charted points are
observed to be in line with each other,
compass bearing to a charted object,
radar range to a charted object,
on certain coastlines, a depth sounding from echo sounder or hand lead
There are some methods seldom used today such as "dipping a light" to
calculate the geographic range from observer to lighthouse
Methods of navigation have changed through history. Each new
method has enhanced the mariner's ability to complete his voyage.
One of the most important judgments the navigator must make is the
best method to use. Some types of navigation are depicted in the
Modern navigation methods
Dead reckoning or DR, in which one advances a prior position using the
ship's course and speed. The new position is called a DR position. It
is generally accepted that only course and speed determine the DR
position. Correcting the DR position for leeway, current effects, and
steering error result in an estimated position or EP. An inertial
navigator develops an extremely accurate EP.
Used at all times.
Pilotage involves navigating in restricted waters with frequent
determination of position relative to geographic and hydrographic
When within sight of land.
Celestial navigation involves reducing celestial measurements to lines
of position using tables, spherical trigonometry, and almanacs.
Used primarily as a backup to satellite and other electronic systems
in the open ocean.
Electronic navigation covers any method of position fixing using
electronic means, including:
Radio navigation uses radio waves to determine position by either
radio direction finding systems or hyperbolic systems, such as Decca,
Omega and LORAN-C.
Losing ground to GPS.
Radar navigation uses radar to determine the distance from or bearing
of objects whose position is known. This process is separate from
radar's use as a collision avoidance system.
Primarily when within radar range of land.
Satellite navigation uses artificial earth satellite systems, such as
GPS, to determine position.
Used in all situations.
The practice of navigation usually involves a combination of these
Mental navigation checks
By mental navigation checks, a pilot or a navigator estimates tracks,
distances, and altitudes which will then help the pilot avoid gross
Further information: Pilotage
Manual navigation through Dutch airspace
Piloting (also called pilotage) involves navigating an aircraft by
visual reference to landmarks, or a water vessel in restricted
waters and fixing its position as precisely as possible at frequent
intervals. More so than in other phases of navigation, proper
preparation and attention to detail are important. Procedures vary
from vessel to vessel, and between military, commercial, and private
A military navigation team will nearly always consist of several
people. A military navigator might have bearing takers stationed
at the gyro repeaters on the bridge wings for taking simultaneous
bearings, while the civilian navigator must often take and plot them
himself. While the military navigator will have a bearing book and
someone to record entries for each fix, the civilian navigator will
simply pilot the bearings on the chart as they are taken and not
record them at all.
If the ship is equipped with an ECDIS, it is reasonable for the
navigator to simply monitor the progress of the ship along the chosen
track, visually ensuring that the ship is proceeding as desired,
checking the compass, sounder and other indicators only
occasionally. If a pilot is aboard, as is often the case in the
most restricted of waters, his judgement can generally be relied upon,
further easing the workload. But should the ECDIS fail, the
navigator will have to rely on his skill in the manual and time-tested
Main article: Celestial navigation
A celestial fix will be at the intersection of two or more circles.
Celestial navigation systems are based on observation of the positions
of the Sun, Moon, Planets and navigational stars. Such systems are in
use as well for terrestrial navigating as for interstellar navigating.
By knowing which point on the rotating earth a celestial object is
above and measuring its height above the observer's horizon, the
navigator can determine his distance from that subpoint. A nautical
almanac and a marine chronometer are used to compute the subpoint on
earth a celestial body is over, and a sextant is used to measure the
body's angular height above the horizon. That height can then be used
to compute distance from the subpoint to create a circular line of
position. A navigator shoots a number of stars in succession to give a
series of overlapping lines of position. Where they intersect is the
celestial fix. The moon and sun may also be used. The sun can also be
used by itself to shoot a succession of lines of position (best done
around local noon) to determine a position.
Main article: Marine chronometer
In order to accurately measure longitude, the precise time of a
sextant sighting (down to the second, if possible) must be recorded.
Each second of error is equivalent to 15 seconds of longitude error,
which at the equator is a position error of .25 of a nautical mile,
about the accuracy limit of manual celestial navigation.
The spring-driven marine chronometer is a precision timepiece used
aboard ship to provide accurate time for celestial observations. A
chronometer differs from a spring-driven watch principally in that it
contains a variable lever device to maintain even pressure on the
mainspring, and a special balance designed to compensate for
A spring-driven chronometer is set approximately to Greenwich mean
time (GMT) and is not reset until the instrument is overhauled and
cleaned, usually at three-year intervals. The difference between
GMT and chronometer time is carefully determined and applied as a
correction to all chronometer readings. Spring-driven chronometers
must be wound at about the same time each day.
Quartz crystal marine chronometers have replaced spring-driven
chronometers aboard many ships because of their greater accuracy.
They are maintained on GMT directly from radio time signals. This
eliminates chronometer error and watch error corrections. Should
the second hand be in error by a readable amount, it can be reset
The basic element for time generation is a quartz crystal
oscillator. The quartz crystal is temperature compensated and is
hermetically sealed in an evacuated envelope. A calibrated
adjustment capability is provided to adjust for the aging of the
The chronometer is designed to operate for a minimum of 1 year on a
single set of batteries. Observations may be timed and ship's
clocks set with a comparing watch, which is set to chronometer time
and taken to the bridge wing for recording sight times. In
practice, a wrist watch coordinated to the nearest second with the
chronometer will be adequate.
A stop watch, either spring wound or digital, may also be used for
celestial observations. In this case, the watch is started at a
known GMT by chronometer, and the elapsed time of each sight added to
this to obtain GMT of the sight.
All chronometers and watches should be checked regularly with a radio
time signal. Times and frequencies of radio time signals are
listed in publications such as
Radio Navigational Aids.
The marine sextant
The marine sextant is used to measure the elevation of celestial
bodies above the horizon.
Further information: Sextant
The second critical component of celestial navigation is to measure
the angle formed at the observer's eye between the celestial body and
the sensible horizon. The sextant, an optical instrument, is used to
perform this function. The sextant consists of two primary assemblies.
The frame is a rigid triangular structure with a pivot at the top and
a graduated segment of a circle, referred to as the "arc", at the
bottom. The second component is the index arm, which is attached to
the pivot at the top of the frame. At the bottom is an endless vernier
which clamps into teeth on the bottom of the "arc". The optical system
consists of two mirrors and, generally, a low power telescope. One
mirror, referred to as the "index mirror" is fixed to the top of the
index arm, over the pivot. As the index arm is moved, this mirror
rotates, and the graduated scale on the arc indicates the measured
The second mirror, referred to as the "horizon glass", is fixed to the
front of the frame. One half of the horizon glass is silvered and the
other half is clear. Light from the celestial body strikes the index
mirror and is reflected to the silvered portion of the horizon glass,
then back to the observer's eye through the telescope. The observer
manipulates the index arm so the reflected image of the body in the
horizon glass is just resting on the visual horizon, seen through the
clear side of the horizon glass.
Adjustment of the sextant consists of checking and aligning all the
optical elements to eliminate "index correction". Index correction
should be checked, using the horizon or more preferably a star, each
time the sextant is used. The practice of taking celestial
observations from the deck of a rolling ship, often through cloud
cover and with a hazy horizon, is by far the most challenging part of
celestial navigation.
Further information: Inertial navigation system
Inertial navigation system
Inertial navigation system is a dead reckoning type of navigation
system that computes its position based on motion sensors. Once the
initial latitude and longitude is established, the system receives
impulses from motion detectors that measure the acceleration along
three or more axes enabling it to continually and accurately calculate
the current latitude and longitude. Its advantages over other
navigation systems are that, once the starting position is set, it
does not require outside information, it is not affected by adverse
weather conditions and it cannot be detected or jammed. Its
disadvantage is that since the current position is calculated solely
from previous positions, its errors are cumulative, increasing at a
rate roughly proportional to the time since the initial position was
input. Inertial navigation systems must therefore be frequently
corrected with a location 'fix' from some other type of navigation
system. The US Navy developed a Ships Inertial
(SINS) during the
Polaris missile program to ensure a safe, reliable
and accurate navigation system for its missile submarines. Inertial
navigation systems were in wide use until satellite navigation systems
(GPS) became available. Inertial
Navigation Systems are still in
common use on submarines, since
GPS reception or other fix sources are
not possible while submerged.
Radio navigation and
Radio direction finder
A radio direction finder or RDF is a device for finding the direction
to a radio source. Due to radio's ability to travel very long
distances "over the horizon", it makes a particularly good navigation
system for ships and aircraft that might be flying at a distance from
RDFs works by rotating a directional antenna and listening for the
direction in which the signal from a known station comes through most
strongly. This sort of system was widely used in the 1930s and 1940s.
RDF antennas are easy to spot on German
World War II
World War II aircraft, as
loops under the rear section of the fuselage, whereas most US aircraft
enclosed the antenna in a small teardrop-shaped fairing.
In navigational applications, RDF signals are provided in the form of
radio beacons, the radio version of a lighthouse. The signal is
typically a simple AM broadcast of a morse code series of letters,
which the RDF can tune in to see if the beacon is "on the air". Most
modern detectors can also tune in any commercial radio stations, which
is particularly useful due to their high power and location near major
Decca, OMEGA, and
LORAN-C are three similar hyperbolic navigation
systems. Decca was a hyperbolic low frequency radio navigation system
(also known as multilateration) that was first deployed during World
War II when the Allied forces needed a system which could be used to
achieve accurate landings. As was the case with Loran C, its primary
use was for ship navigation in coastal waters. Fishing vessels were
major post-war users, but it was also used on aircraft, including a
very early (1949) application of moving-map displays. The system was
deployed in the North Sea and was used by helicopters operating to oil
OMEGA Navigation System
OMEGA Navigation System was the first truly global radio
navigation system for aircraft, operated by the
United States in
cooperation with six partner nations. OMEGA was developed by the
United States Navy for military aviation users. It was approved for
development in 1968 and promised a true worldwide oceanic coverage
capability with only eight transmitters and the ability to achieve a
four-mile (6 km) accuracy when fixing a position. Initially, the
system was to be used for navigating nuclear bombers across the North
Pole to Russia. Later, it was found useful for submarines. Due to
the success of the
Global Positioning System
Global Positioning System the use of Omega declined
during the 1990s, to a point where the cost of operating Omega could
no longer be justified. Omega was terminated on September 30, 1997 and
all stations ceased operation.
LORAN is a terrestrial navigation system using low frequency radio
transmitters that use the time interval between radio signals received
from three or more stations to determine the position of a ship or
aircraft. The current version of LORAN in common use is LORAN-C, which
operates in the low frequency portion of the EM spectrum from 90 to
110 kHz. Many nations are users of the system, including the United
States, Japan, and several European countries.
Russia uses a nearly
exact system in the same frequency range, called CHAYKA. LORAN use is
in steep decline, with
GPS being the primary replacement. However,
there are attempts to enhance and re-popularize LORAN. LORAN signals
are less susceptible to interference and can penetrate better into
foliage and buildings than
Radar navigation and Doppler radar
Radar ranges and bearings can be very useful navigation.
When a vessel is within radar range of land or special radar aids to
navigation, the navigator can take distances and angular bearings to
charted objects and use these to establish arcs of position and lines
of position on a chart. A fix consisting of only radar information
is called a radar fix.
Types of radar fixes include "range and bearing to a single
object," "two or more bearings," "tangent bearings," and
"two or more ranges."
Parallel indexing is a technique defined by William Burger in the 1957
book The Radar Observer's Handbook. This technique involves
creating a line on the screen that is parallel to the ship's course,
but offset to the left or right by some distance. This parallel
line allows the navigator to maintain a given distance away from
Some techniques have been developed for special situations. One, known
as the "contour method," involves marking a transparent plastic
template on the radar screen and moving it to the chart to fix a
Another special technique, known as the Franklin Continuous Radar Plot
Technique, involves drawing the path a radar object should follow on
the radar display if the ship stays on its planned course. During
the transit, the navigator can check that the ship is on track by
checking that the pip lies on the drawn line.
In the modern era, smartphones act as personal
GPS navigators for any
Satellite System or GNSS is the term for satellite
navigation systems that provide positioning with global coverage. A
GNSS allow small electronic receivers to determine their location
(longitude, latitude, and altitude) to within a few metres using time
signals transmitted along a line of sight by radio from satellites.
Receivers on the ground with a fixed position can also be used to
calculate the precise time as a reference for scientific experiments.
As of October 2011, only the
United States NAVSTAR Global Positioning
System (GPS) and the Russian
GLONASS are fully globally operational
GNSSs. The European Union's
Galileo positioning system
Galileo positioning system is a next
generation GNSS in the initial deployment phase, scheduled to be
operational by 2013.
China has indicated it may expand its regional
Beidou navigation system
Beidou navigation system into a global system.
More than two dozen
GPS satellites are in medium
transmitting signals allowing
GPS receivers to determine the
receiver's location, speed and direction.
Since the first experimental satellite was launched in 1978,
become an indispensable aid to navigation around the world, and an
important tool for map-making and land surveying.
GPS also provides a
precise time reference used in many applications including scientific
study of earthquakes, and synchronization of telecommunications
Developed by the
United States Department of Defense,
officially named NAVSTAR
Satellite Timing And Ranging
Global Positioning System). The satellite constellation is managed by
United States Air Force 50th Space Wing. The cost of maintaining
the system is approximately US$750 million per year, including the
replacement of aging satellites, and research and development. Despite
GPS is free for civilian use as a public good.
Ships and similar vessels
Day's work in navigation
The Day's work in navigation is a minimal set of tasks consistent with
prudent navigation. The definition will vary on military and civilian
vessels, and from ship to ship, but takes a form resembling:
Maintain a continuous dead reckoning plot.
Take two or more star observations at morning twilight for a celestial
fix (prudent to observe 6 stars).
Morning sun observation. Can be taken on or near prime vertical for
longitude, or at any time for a line of position.
Determine compass error by azimuth observation of the sun.
Computation of the interval to noon, watch time of local apparent
noon, and constants for meridian or ex-meridian sights.
Noontime meridian or ex-meridian observation of the sun for noon
Running fix or cross with Venus line for noon fix.
Noontime determination the day's run and day's set and drift.
At least one afternoon sun line, in case the stars are not visible at
Determine compass error by azimuth observation of the sun.
Take two or more star observations at evening twilight for a celestial
fix (prudent to observe 6 stars).
Main article: Passage planning
Poor passage planning and deviation from the plan can lead to
groundings, ship damage and cargo loss.
Passage planning or voyage planning is a procedure to develop a
complete description of vessel's voyage from start to finish. The plan
includes leaving the dock and harbor area, the en route portion of a
voyage, approaching the destination, and mooring. According to
international law, a vessel's captain is legally responsible for
passage planning, however on larger vessels, the task will be
delegated to the ship's navigator.
Studies show that human error is a factor in 80 percent of
navigational accidents and that in many cases the human making the
error had access to information that could have prevented the
accident. The practice of voyage planning has evolved from
penciling lines on nautical charts to a process of risk
Passage planning consists of four stages: appraisal, planning,
execution, and monitoring, which are specified in International
Maritime Organization Resolution A.893(21), Guidelines For Voyage
Planning, and these guidelines are reflected in the local laws of
IMO signatory countries (for example, Title 33 of the U.S. Code of
Federal Regulations), and a number of professional books or
publications. There are some fifty elements of a comprehensive passage
plan depending on the size and type of vessel.
The appraisal stage deals with the collection of information relevant
to the proposed voyage as well as ascertaining risks and assessing the
key features of the voyage. This will involve considering the type of
navigation required e.g. Ice navigation, the region the ship will be
passing through and the hydrographic information on the route. In the
next stage, the written plan is created. The third stage is the
execution of the finalised voyage plan, taking into account any
special circumstances which may arise such as changes in the weather,
which may require the plan to be reviewed or altered. The final stage
of passage planning consists of monitoring the vessel's progress in
relation to the plan and responding to deviations and unforeseen
Navigation for cars and other land-based travel typically uses maps,
landmarks, and in recent times computer navigation ("satnav", short
for satellite navigation), as well as any means available on water.
Computerized navigation commonly relies on
GPS for current location
information, a navigational map database of roads and navigable
routes, and uses algorithms related to the shortest path problem to
identify optimal routes.
Integrated bridge systems
Electronic integrated bridge concepts are driving future navigation
system planning. Integrated systems take inputs from various ship
sensors, electronically display positioning information, and provide
control signals required to maintain a vessel on a preset course.
The navigator becomes a system manager, choosing system presets,
interpreting system output, and monitoring vessel response.
Integrated Bridge System, integrated on an Offshore Service Ship
Bowditch's American Practical Navigator
^ Bowditch, 2003:799.
^ a b c Rell Pros-Wellenhof, Bernhard (2007). Navigation: Principles
of Positioning and Guidances. Springer. pp. 5–6.
^ The Ty Pros Companion to Ships and the Sea, Peter Kemp ed., 1976
^ Comandante Estácio dos Reis (2002). Astrolábios Náuticos. INAPA.
^ "Archived copy". Archived from the original on 2012-11-22. Retrieved
^ Swanick, Lois Ann. An Analysis Of Navigational Instruments In The
Age Of Exploration: 15th Century To Mid-17th century, MA Thesis, Texas
A&M University, December 2005
^ Online Etymology Dictionary
^ a b c d Bowditch, 2003:4.
^ Norie, J. W. (1828). New and Complete Epitome of Practical
Navigation. London. p. 222. Archived from the original on
2007-09-27. Retrieved 2007-08-02.
^ a b Norie, J. W. (1828). New and Complete Epitome of Practical
Navigation. London. p. 221. Archived from the original on
2007-09-27. Retrieved 2007-08-02.
^ Taylor, Janet (1851). An Epitome of
Navigation and Nautical
Astronomy (Ninth ed.). p. 295f. Retrieved 2007-08-02.
^ Britten, Frederick James (1894). Former Clock & Watchmakers and
Their Work. New York: Spon & Chamberlain. p. 230. Retrieved
2007-08-08. Chronometers were not regularly supplied to the Royal Navy
until about 1825
^ Lecky, Squire, Wrinkles in Practical Navigation
^ Roberts, Edmund (1837). "Chapter XXIV―departure from Mozambique".
Embassy to the Eastern courts of Cochin-China, Siam, and Muscat :
in the U. S. sloop-of-war Peacock ... during the years 1832-3-4
(Digital ed.). Harper & brothers. p. 373. Retrieved April 25,
2012. ...what I have stated, will serve to show the absolute necessity
of having firstrate chronometers, or the lunar observations carefully
attended to; and never omitted to be taken when practicable.
^ a b c d e Maloney, 2003:615.
^ a b c Maloney, 2003:614
^ Maloney, 2003:618.
^ Maloney, 2003:622.
^ a b c d e f g h i j k l Bowditch, 2002:1.
^ Federal Aviation Regulations Part 1 §1.1
^ a b c d e f g h i Bowditch, 2002:105.
^ a b c d e f g h i j k l m n o p q r s t Bowditch, 2002:269.
^ Maloney, 2003:744.
^ Bowditch, 2002:816.
^ a b c d National Imagery and Mapping Agency, 2001:163.
^ a b c National Imagery and Mapping Agency, 2001:169.
^ National Imagery and Mapping Agency, 2001:164.
^ a b National Imagery and Mapping Agency, 2001:182.
GPS Overview from the NAVSTAR Joint Program Office Archived
2006-09-28 at the Wayback Machine.. Accessed December 15, 2006.
^ Turpin and McEwen, 1980:6-18.
^ "Regulation 34 - Safe Navigation". IMO RESOLUTION A.893(21) adopted
on 25 November 1999. Retrieved March 26, 2007.
^ a b c d "ANNEX 24 – MCA Guidance Notes for Voyage Planning". IMO
RESOLUTION A.893(21) adopted on 25 November 1999. Retrieved March 26,
^ "ANNEX 25 – MCA Guidance Notes for Voyage Planning". IMO
RESOLUTION A.893(21) adopted on 25 November 1999. Retrieved January
Cutler, Thomas J. (December 2003). Dutton's Nautical
ed.). Annapolis, MD: Naval Institute Press.
Department of the Air Force (March 2001). Air
Department of the Air Force. Archived from the original (PDF) on
2007-03-25. Retrieved 2007-04-17.
Great Britain Ministry of Defence (Navy) (1995). Admiralty Manual of
Seamanship. The Stationery Office. ISBN 0-11-772696-6.
Bernhard Hofmann-Wellenhof; K. Legat; M. Wieser (2003). Navigation:
principles of positioning and guidance. Springer.
ISBN 978-3-211-00828-7. Retrieved 7 February 2012.
Maloney, Elbert S. (December 2003). Chapman Piloting and Seamanship
(64th ed.). New York, NY: Hearst Communications Inc.
National Imagery and Mapping Agency
National Imagery and Mapping Agency (2001). Publication 1310: Radar
Navigation and Maneuvering Board Manual (7th ed.). Bethesda, MD: U.S.
Government Printing Office. Archived from the original (PDF) on
Turpin, Edward A.; McEwen, William A. (1980). Merchant Marine
Officers' Handbook (4th ed.). Centreville, MD: Cornell Maritime Press.
Encyclopædia Britannica (1911). "Navigation". In Chisholm, Hugh.
Encyclopædia Britannica. 19 (11th ed.). Retrieved 2007-04-17.
Encyclopædia Britannica (1911). "Pytheas". In Chisholm, Hugh.
Encyclopædia Britannica. 22 (11th ed.). Retrieved 2007-04-17.
Raol, Jitendra; Gopal, Ajith (2013), Mobile Intelligent Autonomous
Systems, CRC Press Taylor and Francis Group 6000 Broken Sound Parkway
NW Suite 300, Boca Raton, FL 33487-2742, USA
Wikiquote has quotations related to: Navigation
Wikimedia Commons has media related to Navigation.
Wikisource has original text related to this article:
Wikivoyage has a travel guide for Navigation.
General Concepts about Marine Navigation
Navigation by Ernest Gallaudet Draper
How to navigate with less than a compass or GPS
History of orienteering
List of orienteering events
Mountain bike orienteering
Amateur radio direction finding
Orienteering in a Compact Area
Organisations / lists
List of clubs
List of orienteers
List of events
Jan Kjellström Festival
Satellite navigation systems
BDS / BeiDou-2 / COMPASS
GPS / NavStar
IRNSS / NAVIC
BDS / BeiDou-1
QZSS / Michibiki