Significant navigation errors jeopardising traffic separation in North Atlantic airspace are uncomfortably commonplace, says the International Federation of Airline Pilots Associations (IFALPA), writes David Learmount.
The International Civil Aviation Organisation North Atlantic working group has issued an oceanic errors safety bulletin (OESB) listing gross navigation errors of 25nm (46km) or more, large height deviations of 300ft (100m) or more) and erosion of longitudinal separation, says IFALPA.
Most navigational errors occur after a flight has been given a track re-clearance and the crew either copy it incorrectly or fail to reprogram and execute the flight management system (FMS) or long range navigation system or update the master computer flight plan and plotting chart, says IFALPA. The FMS crosschecks should include distance and track checks between the new waypoints. In an augmented crew, the captain should ensure that non-flying crew are aware of the reclearance details, says IFALPA, adding that none of these procedures is new or unpublished.
IFALPA also says some crews appear to need reminding that a flight-level change filed in the crew’s flight plan does not constitute a clearance to change level without confirmation and, in the event of a loss of communication, the drill in the North Atlantic is to maintain the last assigned flight level, not to change level at an assigned point unless able to get positive clearance. Likewise advice to “expect” a different flight level on reaching a certain point is not a clearance to change level without voice or controller/pilot datalink communications confirmation before executing the change, says IFALPA.
Source: Flight International
