Portal:Civil Aeronautics Board

“ On January 12, 1960, the Board recommended to the Administrator, Federal Aviation Agency, that flight recorders be installed in all new transport-type airplanes and presently operating turbine-powered transport-type airplanes. Subsequent to that date and as a result of the information gained from the flight recorder in this accident, the Board has expressed the opinion to the Administrator, Federal Aviation Agency, that recorders should also be installed and operating during the training, test, and ferry-flight operations of these air carrier airplanes. ”

“ An experimental pilot for Boeing Airplane Company testified that should all control pressure be relaxed during an approach maneuver while simulating failure of 50 percent of the power units concentrated on the right side with landing gear extended and flaps 30 degrees extended, the Boeing 707 would yaw and roll to the right. Approximately five to seven seconds would be required to stop the roll before the aircraft reached a 90-degree bank. Recovery could be accomplished by applying full opposite aileron and rudder and reducing power on all engines. ”

“ First, it is believed that a prudent instructor would keep ahead of the maneuver, especially in jet transition training and particularly in the type maneuver being conducted, and prevent the development of a critically unsafe condition. Secondly, the testimony given by a Boeing test pilot attested that evasive maneuvers could be accomplished successfully even though the aircraft was in an asymmetrical power condition. ”

“ As the aircraft passed the inverted position the yaw angle was reduced considerably, indicating that some corrective action had been taken in the form of advancing the thrust levers on Nos. 3 and 4 engines and applying full left rudder and aileron. Positive acceleration was held at 1—1/2 to 1-3/4 g.
As the aircraft passed the 270-degree roll position it was in a zero yaw condition. Acceleration was held at approximately 2 g, which is in the buffet range and is the tightest pullout that the aircraft could make. The power was then nearly symmetrical. ”

“ Flight Engineer Edgar Allen Freeman, age 36, was employed by American Airlines on April 11, 1949, as a flight engineer. He held a valid FAA commercial pilot certificate with instrument rating, and a flight engineer certificate with ratings in DC-6 and DC-7 aircraft. He had over 10,200 flying hours as of May 29, 1959. His second-class physical examination was completed on May 29, 1959. He had completed the special Boeing 707 ground training course, had performed two periods of Boeing 707 training, and had accumulated a total of 7.30 hours of Boeing 707 aircraft time. ”

“ This apparent conflict of factual evidence would be logical if, at the start of loss of control, while operating with Nos. 3 and 4 engines reduced to idle thrust their power levers were advanced, quickly to the full-thrust position. The higher power established by advancing the thrust levers would not be reflected on the oil temperature gages during the elapsed time to ground contact. In view of the relatively low altitude as which control was lost, it is concluded that this sequence of events occurred. ”

“ The crew reported on left base leg for runway 23, was given clearance to land, and was informed that the wind was from 230 degrees at 10 to 15 knots. The last communication from the crew was the acknowledgement of landing clearance and wind information, at which time nothing of an unusual nature was reported. ”

“ The yaw and nearly stalled condition indicated on the flight recorder trace were verified by the ground impact marks at the crash site.
There was no control or actuator position by which power being produced at impact could be determined. The energy expended in halting rotation of the engines, as evidenced by the extent of damage from rotational interference, was the primary means of determining the approximate power at impact. Rotational damage indicated all engines were producing appreciable power at impact. Unstacking of the N1 compressors of Nos. ”

“ The operational phase of the investigation was held at the Henry Perkins Hotel, Riverhead, Long Island, New York, on August 27, 1959. The technical phase of the investigation was held at the Forest Hills Inn, Forest Hills, Long Island, New York, October 7, 1959. ”