American Airlines Flight 327

American Airlines Flight 327 was a scheduled flight between T. F. Green Airport near Providence, Rhode Island and Tulsa Municipal Airport in Tulsa, Oklahoma, with ten intermediate stops. On January 6, 1957, the Convair CV-240-0 performing the flight crashed while performing an instrument approach to Tulsa Municipal Airport, killing one of the occupants and injuring seven. Weather conditions in the area were poor, and the aircraft descended through dense clouds and fog. As it approached the runway, it flew lower than the intended path and crashed into the ground 3.6 mi north of the approach end of the runway. The probable cause of the crash was determined to be the captain's lack of alertness in allowing the first officer to continue an instrument descent to an altitude too low to permit terrain clearance.

Background

Flight 327 was a regularly scheduled flight between T. F. Green Airport near Providence, Rhode Island and Tulsa Municipal Airport with intermediate stops at Logan Airport in Boston; LaGuardia Airport in New York City; Hancock Airport in Syracuse, New York; Rochester Municipal Airport in Rochester, New York; Willow Run Airport near Detroit; Midway Airport in Chicago; Lambert Municipal Airport near St. Louis; Springfield Municipal Airport in Springfield, Missouri; and Joplin Municipal Airport near Joplin, Missouri. It was operated by American Airlines using one of the company's 40-passenger Convair CV-240 twin radial engine aircraft. The airline operated this type of aircraft on its short-haul routes between 1948 and 1964.

On January 5, 1957, the scheduled flight's first legs between Providence and Chicago were uneventful, but its departure from Chicago was delayed as maintenance technicians in Chicago worked on a problem with the plane's fire alarm warning system. The problem caused warning flights to flash and a warning bell to ring. Technicians repaired the problem, and the outbound flight to St. Louis left one hour and forty minutes late. The problem with the fire alarm warning system did not occur again after the repairs. The aircraft left Joplin at 11:23 p.m. Central Standard Time, en route to Tulsa, with seven passengers, two pilots, and one flight attendant.

Accident

At 11:47 p.m., as the flight approached Tulsa, the crew contacted the Tulsa approach controller, who relayed the current weather report. That weather report included a ceiling of 600 ft, a visibility of 2.5 mi, very light drizzle and fog, and calm winds. As the aircraft approached the airport, the crew asked the controller if they should expect any delays due to other aircraft taking off or landing, and were told that the only other traffic in the area was then making an ILS approach. Shortly after that, the controller advised the flight that the visibility had dropped to 1.75 mi and that the United States Weather Bureau was checking the ceiling. He asked if the pilots would prefer the Owasso straight-in approach from the north, or if they would prefer an ILS approach, and the pilots responded that they would make the Owasso approach. At midnight, the flight was cleared to land on runway 17L. Two minutes later, the controller gave a weather update to the flight, which included a measured ceiling of only 200 ft, visibility 1.75 mi and very light drizzle and fog. This transmission was not acknowledged by the pilots and all other attempts by the controller to contact the pilots were unsuccessful. At one minute after midnight on January 6, the aircraft crashed into a hillside west of Owasso, Oklahoma, 3.6 mi north of the approach end of the runway.

The plane first hit the top of a tree, then struck the ground, leaving deep tire imprints and gouges from the propellers in the ground. The landing gear collapsed and the aircraft slid along the ground, then became airborne again as it glided over a ravine, and finally came to rest 540 ft from the initial point of impact. The aircraft stopped under a high voltage power line, leaking aviation fuel, but there was no fire. The wings were separated from the aircraft, and the engines were torn off and found near the main wreckage. The nose section of the fuselage was crushed, and both pilot seats in the cockpit were torn from their sliding tracks. There was substantial damage to the rest of the fuselage, including a buckling of the structure in the cabin area, which distorted the cabin floor, causing seats to detach.

The accident was the first fatal accident that American Airlines had experienced since the crash of Flight 476 in August 1955.