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Aviation Sri Lanka 

Air Traffic Engineering
Air Traffic Control
Aircraft Procedure
Next Generation
Aviation Acronyms
Radar Simulator

Learn before fly 

This page and its sub pages are specially devoted to explain all the theoretical background and engineering aspects of air navigation. We are trying to explain all the ATC and Pilot procedures from the Airport terminal to flight's destination. In order for easy navigation of the site for beginners, the content page has been divided into 4 categories.

Following animations are real time explanations for air navigation. They are explained in  Air Traffic Engineering Page.  


Localizer View

Glide Path View


Finding the way from one place to another is called NAVIGATION. Moving of an aircraft from one point to another is the most important part for any kind of mission. Plotting on the paper or on the map a course towards a specific area of the earth , in the passed, used to be a task assigned to a specialized member of the aircraft's crew such a navigator. Such a task was quite complicated and not always accurate. Since it depended on the observation , using simple maps and geometrical instruments for calculations. Today, aerial navigation has become an art which nears to perfection. Both external Navaids (Navigational Aids) and on-board systems help navigate any aircraft over thousand of miles with such accuracy that could only be imagined a few decades ago.  

The Method of Navigation

There are three main methods of air navigation. There are:

1. Pilotage 

2. Dead Reckoning  

3. Radio.

Pilotage or Piloting is the most common method of air navigation. This method, the pilot keeps on course by following a series of landmarks on the ground. Usually before take-off, pilot will making pre-flight planning , the pilot will draws a line on the aeronautical map to indicate the desired course. Pilot will notes various landmarks , such as highways , railroad tracks, rivers , bridges . As the pilot flies over each of landmark , pilot will checks it off on the chart or map. If the plane does not pass directly over the landmark , the pilot will know that he has to correct the course.

Dead Reckoning is the primary navigation method used in the early days of flying. It is the method on which Lindberg relied on his first trans-Atlantic flight. A pilot used this method when flying over large bodies of water, forest, deserts. It demands more skill and experience than pilotage does. It is based on time, distance, and direction only. The pilot must know the distance from one point to the next, the magnetic heading to be flown. Pilot works on the pre-flight plan chart , pilot plan a route in advance. Pilot calculate the time to know exactly to reach the destination while flying at constant speed. In the air, the pilot uses compass to keep the plane heading in the right direction. Dead reckoning is not always a successful method of navigation because of changing wind direction. It is the fundamental of VFR (Visual Flight Rule) flight.

Radio Navigation is used by almost all pilots. Pilots can find out from an aeronautical chart what radio station they should tune to in a particular area. They can then tune their radio navigation equipment to a signal from this station. A needle or LCD on the navigation equipment tells the pilot where they are flying to or from station, on course or not .

Pilots have various navigation aids that help them takeoff, fly, and land safely. One of the most important aids is a series of air route traffic control , operated throughout the world. Most of the traffic control uses a radar screen to make sure all the planes in its vicinity are flying in their assigned airways. Airliners carry a special type of radar receiver and transmitter called a transponder. It receives a radar signal from control center and immediately processes it back to the center with some movement information of the aircraft. When the signal got to the ground, it makes the plane show up on the radar screen.

Pilots have special methods for navigating across oceans. Three commonly used methods are:

1. Inertial Guidance

    This system has computer and other special devices that tell pilots where are the plane located.

2.LORAN Long Range Navigation 

    The plane has equipment for receiving special radio signals sent out continuous from transmitter stations.      

    The signals will indicate the plane location

3.GPS (Global Positioning System). 

GPS is the only system today able to show your exact position on the earth any time, anywhere, and any weather. The system receiver on the aircraft will receives the signals from satellites around the globe.