World Air Ops | NAT | Doc 007 MNPS Guidance

Guidance concerning Air Navigation in and above the NAT MNPSA CHAPTER 8e) preparing a new plotting chart.8.4.7 When reviewing the causes of navigation errors the NAT CMA has noted that numerousoperator reports make reference to crew breaks in their explanation of the circumstances of the error. In alldimensions, errors are more likely to occur where a clearance or re-route, speed or level change has beencommunicated to a crew and either not been actioned completely, or has been incorrectly or incompletelyprocessed before a relief crew member has started duty. Operators’ SOPs are generally consistent in regardto the importance of properly handing over, and taking control, and if adopted with due diligence, wouldforestall the development of an error. However, human factors often confound the best laid SOPs, anddistraction or human failings can contribute to the omission of all, or a part of, the process handed over bythe departed crew member for subsequent action. Flights requiring crew augmentation, particularly, ultralong-haulflights present specific issues as regards to crew relief. With the requirement to have the aircraftcommander and the designated co-pilot on duty for critical stages of the flight i.e.: take off and landing,sometimes crew changes then occur during times when critical information is being received such as oceanicclearances or conditional clearances and/or company communications such as re-dispatch etc. It isimperative that during these crew changes, a thorough turnover briefing takes place so that the incomingcrew is aware of all clearances and requirements for the segment of the flight, especially those involvingconditional re-clearances such as a change of level at specific points or times.8.4.8 Strict adherence to all the above procedures should minimise the risk of error. However,flight deck management should be such that one pilot is designated to be responsible for flying the aircraftwhilst the other pilot carries out any required amendments to documentation and reprogramming of thenavigation systems - appropriately monitored by the pilot flying the aircraft, as and when necessary.Approaching the Ocean8.4.9 Prior to entering MNPS Airspace, the accuracy of the LRNSs should be thoroughly checked,if necessary by using independent navigation aids. For example, INS position can be checked by referenceto en route or proximate VOR/DMEs, etc. However, with a modern FMS, the system decides which LRNSis to be used, and indeed, the FMS may be taking information from DMEs (and possibly VORs) as well asthe LRNS carried. Nevertheless, in spite of all this modern technology and even if the FMS is using GPS, itis still worthwhile to carry out a 'reasonableness' check of the FMS/GPS position, using (for example)DME/VOR distance and bearing.8.4.10 When appropriate and possible, the navigation system which, in the opinion of the pilot, hasperformed most accurately since departure should be selected for automatic navigation steering.8.4.11 In view of the importance of following the correct track in oceanic airspace, it is advisable atthis stage of flight that, if carried, a third pilot or equivalent crew member should check the clearancewaypoints which have been inserted into the navigation system, using source information such as the trackmessage or data link clearance if applicable.Entering the MNPS Airspace and Reaching an Oceanic Waypoint8.4.12 When passing waypoints, the following checks should be carried out:a) just prior to the waypoint, check the present position co-ordinates of each navigation systemagainst the cleared route in the Master Document, andb) check the next two waypoints in each navigation system against the Master Document.c) at the waypoint, check the distance to the next waypoint, confirm that the aircraft turns in thecorrect direction and takes up a new heading and track appropriate to the leg to the nextwaypoint.NAT Doc 007 54 Edition 2010