Learning Resources
Lesson
Navigation is a purposeful activity with the express intent of getting safely and efficiently from one location to another.
Land-based Navigation
On land, road or rail routes are fixed, with a visual reference systems of signs, lights and rules. Navigation involves selecting routes, calculating travel times, and observing rules and regulations. Maps are a primary visual reference system. Transportation maps include roads, rail lines, physical features, and distances. They also use the latitude and longitude grid.
- The Atlas of Canada includes many types of maps.
- Typical of general road maps, the Newfoundland and Labrador Scenic Routes site provides road information and travel information.
- Maps use a variety of symbols to illustrate natural and human-made features.
- Tunnels and bridges in Canada, for example, are shown with these symbols. This site has a comprehensive listing of map symbols used in Canada.
- This Salford/Manchester (UK) map provides excellent detail for roads and railways, including road and rail transportation services. The page is a pdf file, and can be zoomed in and out (magnified) up to 1600%. Check out the legend in the upper left.
While maps provide information to get you started on a journey, signs and lights give specific directions about how to use roadways. Railways, because of their nature, require different signs and signals than roads. However, they do have similar requirements for lights that indicate that the train should stop, proceed with caution, or proceed normally.
Land-based navigation relies on visual references beside the road and railways. they take the form of signs, signals, and lights. When combined with maps, people can plan and execute trips with relative ease
Water-based Navigation
Water based transportation also has 'fixed' routes, called shipping lanes, complete with rules and regulations. The major differences relate to how the vessel operators know where they are when there are no visible reference points, and when water and weather conditions can easily move the vessel off course. Water-based navigation can be divided into two distinct groupings—coastal, and ocean.
Coastal navigation usually occurs within sight of land, or some physical marker such as buoys and lights. It has a complex set of visual aids including lighthouses, buoys, and reference points. Charts are a primary visual reference system. They include coastlines, obstructions to shipping, water depths, shipping lanes and channels, locations and reference information for all coastal navigation aids, reference information for Loran C, and a Latitude and Longitude grid. The latter is a critical part of navigation at sea. Knowing your exact position is the basis for navigation.
Ocean navigation occurs out of sight of land. The only visual references are the stars and the sun. Navigation has traditionally relied on the magnetic compass, star and sun readings using navigation instruments, and careful record keeping of time, heading, speed, and distance travelled. All this was compared periodically to position fixes (readings taken of sun and star positions at precise times of the day) with instruments. Early instruments such as those used by the Vikings were very crude. Into the latter part of the 19th century, instruments had improved dramatically. Many of these instruments are still available and in everyday use. Modern instruments include GPS, short-wave radio, satellite radio.
Ocean navigation is complicated by the fact that the earth is round. On land, and in coastal regions, that can be mostly ignored because of the visual references that are usually available. Courses on the ocean follow curved paths. The compass heading needs to be modified periodically to keep the ship on the correct course.
- SailingIssues has a free online introductory navigation course. Although more detailed than you need for this course, it has excellent information in an easy to read layout. Look particularly for information on
- positions, great circles, time zones
- Mercator charts, how charts are organized, coordinates (lat-long), distances, and symbols
- compasses and magnetic courses, magnetic north and true north
- plotting and piloting, ranges, line of position, position fix, estimated position, dead reckoning, and notation
- navigation aids, lights, buoys,
- The Canadian Coast Guard has excellent materials about all aspects of aids to navigation, including lighthouses, electronic aids, and buoys at its Aids to Navigation site. Navigate through the site using the list of titles on the left side of the page.
Air-based Navigation
Air navigation falls into two general categories—visual flight rules (VFR), and instrument flight rules (IFR). You may wish to explore Emerald Air, a virtual airline with excellent information on flying topics. Look particularly at the training topics, and if you are a Flight Simulator player, at the Flight Simulator add-ons.
With VFR, the pilot follows visual references on the ground, including roads, rivers, landmarks such as mountains and buildings, towns and so on and compares them to charts. Charts show typical map information, plus heights (altitudes) of specific features. The plane's onboard altimeter is used with reference to the chart information to ensure the plane and a topographical feature or building do not try to share the same space. Charts also show magnetic bearings and are used with the plane's compass to determine if the pilot is on course, or to plot a course. As you might expect, VFR flights tend to be at lower altitudes. As well, VFR flying requires a radio and at least these 4 instruments — airspeed, altimeter, attitude indicator, and turn and slip indicator.
With IFR, the pilot uses instruments to navigate. IFR is required for all commercial planes and for higher altitudes, flying in inclement weather, and landing when visibility is poor. In addition to the VFR instruments, IFR requires VOR (VHF Omnidirectional Range navigation system), ILS (Instrument Landing System), ADF (), and DME (Distance Measuring Equipment).
Air-based transportation also uses 'fixed' routes, with the added dimension of altitude. Routes in one direction (for example, west) operate in one altitude, while flights in the other direction operate 10,000 feet higher. Air navigation uses radio beacons and navigation radios, air traffic controllers, radar and GPS. NavCanada is responsible for air traffic in Canada. They provide online flight planning weather information. Select from a variety of types of information useful to pilots and get visual charts and weather images. Flight communications begins with flight planning. The Isle of Man Airport in the UK provides a tutorial on flight planning. The site is mainly useful to show the types of information required in a flight plan.
Activity
Assigned activities
Investigate available commercial navigation technologies related to positioning, weather, voice and data communications. Compile a list, complete with features and pricing info.
Test Yourself
There is no self test for this lesson.