(June 2011) The captain had completed an entry of the navigation log after passing the previous oceanic waypoint. The FMS, utilizing a series of inertial navigation systems along with two GPS receivers, was tracking the assigned course to an accuracy that was no wider than the cockpit of the 777. The digital display of the altitude pointer indicated that the airplane had fluctuated no more than five feet. The ATC page of the comm screen verified that Shanwick Oceanic had automatically received the position report. No voice calls were required. Life was good.
Well … right up until the moment that the EICAS (engine instrument and crew alerting system) screen annunciated an amber message: “fuel imbalance.”
