Aviation Navigation

Reading a Sectional Chart

Sectional Charts are meant to only show a section of a flight region. These charts emphasize only landmarks and features that would be important to a pilot for navigation during flight. Tall, man-made structures and natural landmarks are indicated along with roadways, rivers and railroad tracks, as these are easily seen and recognized by pilots from the air. Topography is referenced by a special color code with lightness or darkness of the color indicating a lower or higher in elevation of the land.

Take a look at the Sectional Chart below and notice how much information it communicates to the pilot. We'll break this Sectional Chart down into layers, so you can easily see how the many important features are noted on the chart. Check the button for any given layer to view that layer; uncheck it to hide the layer. Select any combination of layers to place them together, so you can view the sectional chart in different ways.



There are a number of important components to this chart. Let's examine them in detail.

 

Elevation

Notice the use of color to show elevation. The color code is given in the box next to the chart. Remember, the darker the shade, the higher the elevation. The lighter the shade, the lower the elevation. Bright yellow indicates a city

elevation

Topography

This layer shows the man-made and natural features that would be easily visible to a pilot during flight. The man-made features include tall towers, roads, railroad tracks, dams, outdoor theaters, race tracks, bridges, lookout towers, power transmission lines, aerial cables, and coast guard stations. The natural features include lakes, rivers and mountain passes. Click the image of the key to topographic symbols at right for a closer view.

obstruction layer

Obstructions
These man-made structures are usually tall radio towers, simply tall towers or they are very tall structures that are not specifically identified on the map. See the key to the right.

airport info

Airport Information

An airport is indicated by the type and length of runway it has. There are also special symbols to indicate if the airport is restricted in any way, if it is a military airport, if it has been abandoned and if it provides services such as fuel. Airports having control towers are shown in blue. Additional data about the airport is given in a blue-lined box. All other airports are shown in magenta. For specific details about an airport, the pilot needs to consult the Airport Facility Directory. Click the key to the right for a closer view.

airport data

Airport Data

The blue-lined box gives details about the airport indicated in blue. (Remember blue airports have control towers!) This data can be lengthy or brief and usually includes radio frequencies, elevation, runway length and lighting availability. Click the key to the right for a closer view.

radio aids

Radio Aids

The symbols listed in the box below inform pilots as to what radio aids are available for their navigation. Click the box for a closer view.

airspace information

Airspace Information

The type of aircraft being flown will determine the airspace in which it should be flown. The floor and/or ceiling for each different airspace designation is sometimes indicated on the chart. Airways, departure and arrival routes are also drawn on the map. Restricted areas and military operation areas are boxed in blue or magenta. Click the box to the right for details.


Miscellaneous symbols

Miscellaneous

These symbols show special activity that can occur in a certain area such as ultralight flying, hang gliding, parachuting and glider operations. If an airport has a flashing beacon, it is also indicated. See the key at right for these symbols.

 

Text

All names are printed in black, blue or magenta and can indicate cities, mountains, rivers and regions.

Compass
Throughout a sectional chart a compass rose is placed to identify to the pilot the orientation to the cardinal points (north, south, east and west).