What is a key feature of IFR approved GPS?

A key feature of IFR approved GPS is its requirement for RAIM (Receiver Autonomous Integrity Monitoring) capability. RAIM is crucial because it ensures the integrity and reliability of the GPS signals being used for navigation under Instrument Flight Rules (IFR). Specifically, RAIM checks the accuracy of the GPS data and ensures that the information provided to the pilot is reliable enough for safe navigation, particularly in critical phases of flight.

IFR operations can have significant safety implications, including flying into cloud cover or on routes where visual references are not available. Therefore, the capability to monitor and confirm the integrity of the GPS signals is vital. Without RAIM, a GPS could potentially provide inaccurate location data, which could lead to navigation errors.

While other features, like backup batteries and synthetic vision, can enhance the functionality and reliability of GPS systems, they are not specifically required for IFR approval. Additionally, synchronization with ATC is important for overall flight management but does not pertain directly to the core functionality and approval criteria of the GPS as it relates to IFR navigation.