Page:CAB Accident Report, Eastern Air Lines Flight 663.pdf/17

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Other reasoning which forces a conclusion that the computed flightpath is not entirely compatible with a probable flightpath is that the crew of EAL 663 acknowledged the turn instructions and "signed off" with the salutation "Good night" some 50 seconds prior to passing abeam PAA 212. Under normal circumstances the EAL DC-7 would have to be at least 3 to 3-1/2 miles from the point of passage at this time. Attachment #3, however, shows a distance of only 1-1/2 miles. Since the crew did not indicate any difficulties with the aircraft it can be presumed that the operation was normal or near normal at the time EAL 663 started the turn to the 170-degree heading. Also, passage would have occurred prior to the "Yeoh" transmission at 1826:19.

A number of calculated flightpaths of EAL 663 were developed by the Board staff taking into account the testimony of the AR-3, DR-1, and DRHO controllers concerning the relative position of the two airplanes at the time EAL was turned to the 170-degree heading, as well as its location at the time the AR-3 controller pointed out the target to the Approach Sequence Controller. The following factors were utilized for one projected flightpath:

(a) EAL 663 precisely at the handoff point described, i.e., three miles from the DPK 228-degree radial and at the time of the handoff (1824:20).

(b) EAL 663 was heading 150 degrees at handoff.

(c) EAL 663 turned to 090 degrees at 1824:30.

(d) EAL 663 turning immediately to 170 degrees upon receiving the turn instructions at 1825:21. (This is despite the fact that the DR-l controller reported that 663 did not turn immediately. However, the immediate turn is used to keep the flightpath as short as possible.)

In order to arrive at the average position as reported by the aforementioned controllers it would be necessary for EAL 663 to have proceeded on a track of approximately 042 degrees instead of the 090 degree heading assigned. In 51 seconds it would have to travel approximately six miles or more at an average groundspeed of 423 knots. Thereafter, the aircraft would have to turn to a heading of approximately 236 degrees and travel the seven miles to the crash site at an average groundspeed of 365 knots. That an aircraft would proceed on a track 50 degrees displaced from the assigned heading without causing some concern and query on the part of the controller is difficult to accept.

Additionally, not only would such a flightpath be necessary, but in order to pass PAA 212 in close proximity in a 90-degree banked turn to the right, it would be necessary for EAL 663 to cross PAA 212's flightpath several times.

Since the above circumstances are completely beyond the capability of the aircraft it must be concluded that the JFK Tower controllers' statements concerning the location of EAL 663 at the time of the turn to 170 degrees and/or the location at the time of handoff are in error.

The locations of EAL 663 reported by the DR-l, DRHO, Approach Sequence and AR-3 controllers could be as much as a mile further west than they indicated. However; the DR-1 controller testified that EAL 663 had already crossed the projected flightpath of PAA 212 when he issued the turn instructions and that PAA 212