What is the primary function of the Global Positioning System (GPS)?

The primary function of the Global Positioning System (GPS) is to provide accurate location and time information globally, regardless of weather conditions. GPS operates through a constellation of satellites that transmit signals to GPS receivers, allowing users to determine their precise position anywhere on Earth. This capability makes it a vital tool for aviation navigation, as it helps pilots and air traffic control maintain accurate flight paths, enhance safety, and improve overall navigation efficiency. The reliability and global coverage of GPS is critical for modern aviation, supporting not only navigation but also various applications that rely on timing and location data.

In contrast, the other options do not accurately describe the core function of GPS. Ground-based systems and manual navigation methods are typically supplementary or alternative approaches, rather than the primary means of navigation offered by GPS. Additionally, a visual chart system, while useful during certain phases of flight, does not provide the automated and continuous positioning that GPS delivers.