Page:NTSB Southern Airways Flight 932 report.pdf/14

 m. s. l. The only runway was Runway 11-29. It was 5, 281 feet long and 150 feet wide, and was of concrete construction. Runway 11 was equipped with high-intensity runway lights, approach lights, and sequence flashers. All lighting was operating satisfactorily. There was no visual approach slope indicator (VASI) system installed.

There was very little level land extending beyond either end of the runway; however, there were other hills of similar size and elevation surrounding the airport. The highest obstacle in the area underlying the localizer was a tree 6,700 feet east of the outer marker, at an elevation of 990 feet m.s.l. By contrast, the Ohio River and Big Sandy River passed within a few miles of the airport at elevations of approximately 500 feet m.s.l. in the north, west, and south quadrants. An area of bright lights surrounding a refinery was located on the west bank of the Big Sandy River just south of the localizer course, about 2 miles west of the runway threshold.

1.11 Flight Recorders The aircraft was equipped with a Sundstrand flight data recorder, Model F-542, S/N 1047. The recorder unit had been exposed to extreme heat in the fire after the impact, but the recording medium magazine was easily removed and the recorded foil surface was virtually undamaged. A readout of the last 10 minutes of normally recorded traces were prepared. The altitude trace was adjusted for an altimeter setting of 29.67 to indicate m.s.l. altitudes, but no other corrections were made to the data. Additional checks of the altitude trace were made as follows:

The last 0.036-inch of foil travel contained sudden deviations in all recorded traces. The aberrant area, equivalent to 21.6 seconds of elapsed time during normal operation, included a 0.009-inch segment without the recording of any parameter trace. With the assistance of the manufacturer, various tests were conducted to duplicate the indications on the flight data recorder foil. Mechanical and electrical checks, g-loading on all three axes with indiscriminate interruptions of electrical