The Inner World of Aeronautical Maps: How Airlines Use Them for Travel
When we think of maps, we often picture them as static representations of the Earth's surface. However, in the aviation world, these maps are dynamic and updated regularly to ensure safe and efficient travel. Airline pilots and aviation professionals rely on a variety of aeronautical charts to navigate their routes. These charts range from detailed approach charts to broader sectional maps. This article delves into the intricacies of these maps and explains their significance in modern aviation.
Understanding Aeronautical Charts
One of the most prominent providers of aeronautical charts is Jeppesen. These charts are essential tools that help pilots navigate their flights, ensuring they are up-to-date with the latest flight information and safe from potential hazards. However, not all maps serve the same purpose, and some are more critical than others.
Sectional Charts: The Foundation of VFR Flying
The first type of chart that new pilots learn to use is the sectional chart. These charts are designed for VFR (Visual Flight Rules) flying and provide a comprehensive view of the airspace around an airport. They are invaluable for pilots who are just starting out, as they are the basis for understanding the layout of airspace and terrain. Sectional charts typically include features such as roads, airports, and other important elements.
Approach Charts: The Most Critical Maps
One of the most detailed and critical maps used by pilots is the approach chart. These charts guide pilots through the final stages of a flight, allowing them to land securely. Approach charts show the airport, runway, and various navigation aids, such as VORs (Very High Frequency Omnidirectional Range) and NDBs (Non-Directional Beacons). Understanding these charts is crucial for ensuring a safe and smooth landing.
The Evolution of Sectional Charts
Sectional charts have undergone significant changes since their inception. The National Oceanic and Atmospheric Administration (NOAA) takes care of updating these charts, working closely with the Federal Aviation Administration (FAA) and other agencies. The process of updating a sectional chart is complex, requiring up to 1800 hours of manual labor. This involves mapping terrain, adding cultural features, and overlaying airspace information.
How Sectional Charts Are Produced
The process of producing a sectional chart involves several stages. First, a topographical base is created using quadrangle maps produced by the U.S. Geological Survey. These maps are reduced 20 times to reach the sectional scale. Each quadrangle map is then reduced to a postage-stamp-sized image on the sectional chart. To this base, man-made features such as roads, airports, and towns are added. Finally, airspace information is overlayed to create the final product.
Updating the Charts
Updating a sectional chart is a meticulous process that requires careful attention to detail. Changes in the landscape, such as new buildings or removed features, are detected through aerial surveys. Additionally, changes in regulations and new airspace features are documented by the FAA and provided to NOAA. The charting process is complex, with up to 40 separate sheets of acetate used to print the sectional, each representing a different type of information.
Ensuring Accurate Charts
To maintain accuracy, NOAA assigns a significant number of personnel to the charting process. About 70 technical staff are dedicated to producing sectional charts, with 62 of them being cartographers. This ensures that the charts are up-to-date and reliable. However, the work is not without its challenges. Legal issues can arise when structures are built in proximity to airports without proper clearance. This highlights the importance of accurate and timely updates to the charts.
Conclusion
Aeronautical charts are the backbone of modern aviation. From sectional charts to approach maps, these tools help pilots navigate their flights with precision and safety. The detailed and complex process of updating these charts ensures that pilots have access to the most accurate information, enhancing the safety of air travel.