5.2 Monitoring Navigation Capability Monitoring by the Operators 5.2.1 Decisions regarding the monitoring of aircraft navigation performance are largely the prerogative of individual Operators. In deciding what records should be kept, Operators should take into account the stringent requirements associated with the MNPS. Operators are required to investigate all occurrences of GNEs (errors of 25 NM or greater, and it is imperative, whether these are observed on ground radar or by the flight crew, that the causes) of track deviations be established and eliminated.
