World Air Ops | NAT | Doc 007 MNPS Guidance

Guidance concerning Air Navigation in and above the NAT MNPSA CHAPTER 15preferably plotted approximately 10 minutes after passing each waypoint, and, ifcircumstances dictate, midway between waypoints. e.g. if one system has failed.e) Check the present, next and next+1 waypoint co-ordinates as shown on the Master Documentagainst those in the steering CDU before transmitting position reports (in performing thesechecks review the LRNS stored co-ordinates in expanded Lat/Long format (not abbreviatedARINC 424 format).f) Check the LRNS indicated magnetic heading and distance to the next waypoint against thoselisted on the Master Document.15.2.3 The procedures outlined in this Section will detect any incipient gross errors, providing thatthe recorded/plotted cleared route is the same as that provided by the controlling ATS authority. If there hasbeen a misunderstanding between the pilot and controller over the actual route to be flown (i.e. an ATC looperror has occurred), then the last drill above, together with the subsequent passing of the position report, willallow the ATS authority the opportunity to correct such misunderstanding before a hazardous track deviationcan develop. The vast majority of instances of waypoint insertion errors occur when the ATC clearedoceanic route segment differs (partly or wholly) from that included in the filed flight plan or that requestedby the pilot. Thorough and diligent checking and cross-checking, by more than one crew member, of thewaypoints entered into the navigation computer, against the received Oceanic Clearance would eliminatemost of these unnecessary and avoidable errors.NAT Doc 007 90 Edition 2010