Page:NTSB Southern Airways Flight 932 report.pdf/15

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power, and attempts mechanically to impede or accelerate foil travel all failed to provide a satisfactory explanation for the aberrations. It was determined that the 0.009-inch skip was caused by a shock of unknown magnitude or origin. Also, though some scribe marks during the 0.035-inch travel were normal in appearance, there was no correlation between the recorded parameters, except that the downward excursions appeared to have been caused by a heavy shock in excess of 30g's

The flight data recorder static pressure source is the aircraft alternative static system. This system is completely separate from the captain's and first officer's normal static pressure systems, except that it is available as a backup source for their instruments, if selected by them. The alternate static ports are located on either side of the aircraft centerline approximately 10 feet forward, and slightly below, the normal static port panels.

The aircraft was also equipped with a Collins cockpit voice recorder (CVR), Model 642-C-1, S/N 508. The unit has sustained considerable impact damage to the electronics package, but there was no damage within the stainless steel case of the tape magazine. There was considerabl "wow and flutter" on the tape, indicating a mechanical distress condition within the recorder. There was also marked interference from background noise and the cockpit speakers. A partial transcript of the readout is attached as Appendix D.

1.12 Wreckage

The aircraft initially struck trees on a hill 5,542 feet west of the runway threshold, and cut a swath 95 feet wide and 279 feet long through the trees on a bearing of 110°, 122 feet right of the Runway 11 centerline extended. Several sections of wing leading edge, one trailing edge flap moveable vane, and a flap track, all from the right wing, and three large sections of radome were located near the swath cut.

The main wreckage site was located 4,219 feet from the threshold of Runway 11, and approximately 225 feet south of the middle marker. The aircraft cut a swath 39° below the horizontal through the trees at the wreckage site and came to rest in an inverted attitude.

The ground elevation at the initial tree impact was 860 feet m.s.l., and the elevation at the break of the tree at this location was 916 feet 2

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