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2.12
Position reporting
2.12.1
Position reports were made in accordance with the operational flight plan, though with some difficulty in the communications. These position reports were commensurate with a functioning INS from which to take navigational information at least so far as waypoint passage was concerned together with forward time estimates and spot winds. In the off-track situation, waypoint passage would have been indicated when the aircraft reached the perpendicular from the waypoint on the desired track. This would have applied regardless of the extent of the cross-track error. Reasonable forward time estimates were possible in the off-track condition because the INS calculated time to go along the desired track and not from the actual position to the position of the next waypoint. The time would therefore run towards zero as the next fictitious waypoint was approached. Conversely the distance to go shown on the INS CDU was the distance from the actual position to that of the next actual waypoint. The indicated distance to the next actual waypoint could not reduce to less than the cross-track error.
Such an indication would have been readily apparent when the CDU alert light came on prior to waypoint passage, if any significant cross-track error was present.
2.12.2
The CDU display showed distance and time on the same selection. However, immediately following waypoint passage an inconsistency between distance and time would not have been readily apparent until the cross-track error became large. On a 300 NM leg, a 50 NM cross-track error would have given a distance error of 4 NM whilst a 100 NM error gave a distance error of 16 NM. As this error became larger it would have become readily apparent when compared with the track distance on the flight plan.
2.12.3
The long range navigation manuals previously mentioned specifically covered actions that should be taken at oceanic waypoints. In particular these included, when the CDU alert light illuminated, a check of each INS position's co-ordinates against the current ATC clearance, the observation of any turn associated with the track-change, the verification of the next waypoint co-ordinates against the flight plan and, after the waypoint passage, plotting the present position on a chart as a further tracking check.
2.13
RC-135 northeast of Kamchatka
2.13.1
In 1983 the USSR stated that at the time that KE 007 was now known to have been flying towards Kamchatka a United States RC-135 was operating in the area to the northwest of NEEVA. This was confirmed by the United States. In 1993, representatives of the Russian Federation provided a track plotted from radar observations, which was allocated a track number 6065 and which indicated some manoeuvring, of an aircraft through this area. The United States provided position information, derived from monitored USSR communications, for KE 007 and for the RC-135, the area of operations of which was centred on 58°00'N, 160°00'E. The proximity of the RC-135 and KE 007 resulted in 1983 in confusion and the plotting of the track of only one aircraft. The United States stated that the closest distance between the two aircraft was 75 NM, based on monitored USSR information; this distance was confirmed by representatives of the Russian Federation in 1993.
2.13.2
The United States, whilst it provided information derived from monitored USSR communications, stated that it was not in possession of first-hand information on the track of KE 007.