GNSSlähestymisjärjestelmien

GNSSlähestymis (GNSS Approach) refers to the use of Global Navigation Satellite Systems, such as GPS, GLONASS, Galileo, and BeiDou, to guide aircraft during the final stages of flight towards landing. This technology allows for precise navigation down to the runway, even in low visibility conditions where traditional ground-based navigation aids may be unavailable or insufficient.

GNSS approaches are categorized based on their accuracy and integrity levels, often denoted by Performance-Based Navigation (PBN) specifications. These include approaches like LNAV (Lateral Navigation), which provides lateral guidance, and LNAV/VNAV (Lateral Navigation/Vertical Navigation), which adds vertical guidance. More advanced approaches, such as LPV (Localizer Performance with Vertical Guidance), can achieve precision approach levels, mimicking the performance of Instrument Landing Systems (ILS).

The implementation of GNSS approaches enhances airspace capacity and efficiency by enabling more direct routes and reducing reliance on fixed ground infrastructure. It also provides access to airports that may not be equipped with traditional landing systems. However, GNSS approaches require certified avionics and trained flight crews, along with robust procedures to ensure safety, especially in the event of GNSS signal degradation or failure. The integrity of the GNSS signal is continuously monitored to provide warnings to pilots if the system is not to be trusted for navigation.