American Flight 157 from New York-LaGuardia to Washington, Dallas and Mexico City was carried out by DC-6 N90728, named “Flagship South Carolina”. The flight to and departure from Washington were uneventful. At 02:54 a descent was started to 6,000 feet. When approaching Nashville the no. 1 engine had started backfiring at intervals of about 20 seconds. Various corrective measures, including the application of alcohol and carburetor heat, and the richening of fuel mixture, were applied but were not successful and the backfiring continued. The no. 1 engine was then feathered at a point about 25 miles southwest of Nashville at approximately 03:00. When 15 miles northeast of Dallas, at 05:36, the flight was given permission to enter the traffic pattern at Love Field, Dallas, with a right-hand turn and instructed to land on runway 36. Weather was fine as the flight turned to final approach. The turn to final placed the aircraft to the left of the runway. Accordingly an “S” turn was made to correct the misalignment. During this “S” turn, the flight engineer noted that the fuel flow meter of no. 4 engine was reading zero and put the booster pump to it. Full throttle was then quickly applied to engines nos. 2, 3 and 4. The no. 4 engine came in with a surge of power (overspeeding), the left wing dropped and the aircraft started to turn to the left. He then retarded throttles nos. 3 and 4 in an attempt to raise the left wing with no. 2 engine. When the wing was partially up he opened throttles Nos. 3 and 4 and called for gear and flaps up. The first officer raised the gear but did not raise the flaps. He then observed that no. 4 tachometer indicated only 1200 rpm, noted that the fuel pressure to that engine was zero, and immediately feathered no. 4 propeller The flight engineer turned on the cross-feed fuel valves. The DC-6 was now flying in a generally northwest direction, across the airport on a heading about 40 degrees to the left of runway 36, in a tail low attitude. The airspeed continued to fall, and the attitude became increasingly nose-high. A stall developed and the left wing struck the wall of hangar no. 7. At about the same time, the left stabilizer struck two crated aircraft engines that were standing in front of the hangar. The aircraft continued ahead swerving to its left. The no. 1 engine struck the ground and tore loose and the aircraft passed through telephone and power lines as it crossed Love Field Drive, bordering the airport. Just beyond Love Field Drive the aircraft struck the ground while approximately level laterally and nose-down about 23 degrees. This contact broke off the entire cockpit and no. 2 engine The remaining portion of the aircraft slid with its right wing tip foremost until the fuselage struck the side of another building. This final impact partially tore off nos. 3 and 4 engines and the entire tail assembly. PROBABLE CAUSE: “The faulty execution of an engine-out approach.”