1. Classification of errors (NAT SPG/27, paragraph 1.2.4, revised NAT SPG/33) CLASS CAUSE A Aircraft not certified for operation in MNPS Airspace B ATC system loop error C Equipment control error encompassing incorrect operation of fully functional FMS or navigation system C Incorrect transcription of ATC clearance or re-clearance into the FMS C Wrong information faithfully transcribed into the FMS e.g. flight plan followed rather than ATC clearance or original clearance followed instead of re-clearance D Other navigation errors, including equipment failure notified to ATC in time for action E Other navigation errors, including equipment failure notified to ATC too late for action F Other navigation errors, including equipment failure of which notification was not received by ATC 2.
