Which system aids in navigation for aircraft?

The Global Positioning System (GPS) is integral to modern aviation as it enables pilots to determine their precise location in real-time, greatly enhancing navigation capabilities. This satellite-based navigation system uses a network of satellites that transmit signals to GPS receivers in aircraft, allowing for accurate positioning anywhere on Earth. By providing information on speed, direction, and altitude, GPS supports both en-route navigation and approaches to airports, significantly improving safety and efficiency in flight operations. The reliance on GPS has become standard in both commercial and general aviation, making it a vital tool for pilots in navigating complex airspace and guiding aircraft accurately to their destinations.

In comparison, while the other systems mentioned may support various functions in aviation, they do not specifically serve the core purpose of navigation in the same comprehensive and globally standardized way that GPS does.