Instrument Rating Exam · Mock exam

ABAS (Aircraft-Based Augmentation System) improves GNSS integrity by using:

• A.Baro-aiding or additional onboard sensors combined with RAIM or FDE algorithms
• B.Ground-based differential correction signals from GBAS stations near the airport
• C.Multiple GNSS constellations (e.g. GPS combined with GLONASS) simultaneously
• D.Geostationary satellite correction signals received onboard