Page:CAB Aircraft Accident Report, American Airlines Flight 320.pdf/3

 reported over the La Guardia range which is 2.8 from the threshold of runway 22, and 4.8 nautical miles from New Rochelle. At 2354:40 it was cleared to continue its approach to runway 22, and was requested to stand by for further clearance. At 2355:20, Flight 320 was cleared to land straight in on runway 22, wind south-southwest 8 knots. At 2355:27, the flight acknowledged by saying "320." There was no further message from the flight.

The crash occurred approximately seven seconds following the final message. Most of the wreckage was found submerged within a 200-foot radius circle, the center of which was located approximately 4,891 feet short of the threshold and 610 feet to the right of the extended centerline of runway 22.

According to the testimony of the crew, the takeoff and climb from Chicago was routine. The autopilot was initially engaged sometime during climb-out in the manual mode position. Since it did not operate correctly in this position it was switched to heading mode which operated satisfactorily and was used throughout the entire trip. The flight was on and off instruments at a cruising altitude of 21,000 feet. The pilot heaters were on during the entire flight.

Some ice was encountered during descent approaching the New York area. However, it was of short duration, so the captain elected not to use the wing heaters. After passing Newark Intersection, a thirty-degree error was reported by the first officer on his RMDI (radio magnetic direction indicator). However, radar vectoring and magnetic compass indications revealed the captain's RMDI was operating satisfactorily.

The aircraft was flown in the New York area at an airspeed of 175 knots or less with approach flaps. The "before landing" checklist was accomplished prior to intercepting the localiser course inbound except for landing flaps, heaters, landing lights, and autopilot which are accomplished later in the landing approach. The landing gear was extended at New Rochelle and the airspeed from New Rochelle inbound was approximately 140 knots.

The first officer stated that during the approach to La Guardia, the ILS switch was in the back course position; sensitivity switch "not desensitized," and a reciprocal heading of the front course localizer of 44 degrees was set up in the course deviation indicator window. The ADF selectors were in ADF position, the autopilot was in the heading mode, steering needle mode selector knob was in the deviation position, both VHF navigational receivers were on the La Guardia ILS, the captain's ADF was tuned to the compass locator at the middle marker (La Guardia), the first officer's to New Rochelle compass locator and, after passing that point, retuned to the La Guardia range.

The surviving flight crew members testified that during the approach, the captain was flying the aircraft by the autopilot; the first officer was handling the communications and assisted the captain; the flight engineer was handling the throttles and maintaining approximately 140 knots on the captain's airspeed indicator.