Practical information: why aviation displays distances in nautical miles

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L’aviation use the nautical miles as distance measurement unit due to their precision and practicality for aerial navigation. Here are some main reasons:

  1. Correspondence with Earth: One nautical mile corresponds to one minute of latitude on the Earth’s surface. This means that lines of latitude are circles that extend around the Earth, and each circle has 60 minutes of latitude. This correspondence makes distance calculations easier for pilots when planning flights.

  2. Map Accuracy: Aeronautical charts used in aviation are based on the Mercator projection, which is designed to minimize distortions in the shape of the land. This means that the latitude lines are straight lines on the map. The distances in nautical miles measured along these lines are therefore more precise.

  3. Compliance with International Rules: Aviation is an international business and nautical miles are a standardized unit of measurement used around the world. This facilitates communication and coordination between pilots, air traffic controllers and other aviation stakeholders globally.

  4. Navigation Calculations: Air navigation systems, such as GPS, provide coordinates in degrees of latitude and longitude. Using nautical miles for distances helps simplify calculations for pilots when planning their routes.

  5. History and Tradition: The use of nautical miles in aviation dates back to when air navigation was closely linked to maritime navigation. Nautical miles were already a well-established unit of measurement in the maritime domain, and this tradition continued in aviation.

In summary, the use of nautical miles in aviation arises from their accuracy, compliance with international standards, ease of use on aeronautical charts, and correspondence to lines of latitude on the Earth’s surface.

John Walker Avatar