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involved significant track deviations as a result of flight crews failing to detect instances where the autopilot had been switched from the INS navigation mode to that required for the maintenance of a constant magnetic heading. While the majority of these errors amounted to less than 60 NM off the intended track, one occurred in May 1983 in which the aircraft reached 250 NM off track. In the latter case the autopilot was in a heading mode, and complacency, boredom and fatigue on all-night, over water flights were cited by the crew as probable factors for their failing to detect the deviation from track through two waypoint passages.
1.16.3.2 An incident in September 1983 involved a B-747 that was rerouted. The captain altered the heading using the autopilot. Following this adjustment he did not reselect INS mode on the navigation mode selector and thus the autopilot did not lock onto the INS track. Neither pilot on the flight deck subsequently checked the mode indicators and thus the absence of a NAV armed and NAV captured indication was overlooked. The crew made no reference to other navigational facilities to monitor the progress of the flight until the flight engineer queried the aircraft's position some two hours later when the aircraft had diverged some 60 NM from track. All of the aircraft's navigation equipment was serviceable. Subsequent information suggested that despite high standards of crew discipline, long flights over the ocean or featureless terrain, at night, in a confined sleep inducing atmosphere have a significant adverse effect on the crew's state of arousal.
1.16.3.3
Several similar cases of an excessive time being taken by crews in such circumstances, to discover errors in INS navigation, were recorded. Not all of the incidents resulted from the flight crew forgetting they had switched the autopilot to heading mode. In some cases it was believed that the autopilot had disengaged without attracting their attention.
2.
2.1
2.1.1
ANALYSIS
Operational flight plan
In 1983 the Korean Air Lines operational flight plans were provided by a contracting company. A copy of the operational flight plan, purported to have been annotated by the pilot and taken on the flight by the crew of KE 007, had been given to the ICAO investigation team by the Korean Air Lines Anchorage office in 1983. In 1993 Korean Air provided another copy of the same flight plan with the same annotations but the fuel table was not crossed out.
2.1.2
In January 1993 representatives of the United States provided another copy of the operational flight plan. This copy was annotated differently from the other two copies and had "ATD 1259" written near the top and waypoint numbering from 1 to 17. This numbering system would not have been used by a flight crew since numbers above 9 would not correspond to waypoints in the INS.
2.1.3
An annotation concerning the equal time point appeared on KE 007's flight plan as well as on the one used by the crew of KE 015 on 31 August 1983 and provided by Korean Air in February 1993. A statement dated 31 July 1985 by the flight dispatcher in the Korean Air Lines' Anchorage office in August 1983 confirmed that he had made these notes on the flight plans for both flights.
2.1.4
Statements by Korean Air personnel in February 1993 established the significance of two groups of numbers and letters written at the top of the flight plan for KE 007, "JCA9" and "GXXO".