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.

[3]: 1 [6] Technicians repaired the problem, and the outbound flight to St. Louis left one hour and forty minutes late.

[6] 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.

That weather report included a ceiling of 600 feet (180 m), a visibility of 2.5 miles (4 km), very light drizzle and fog, and calm winds.

Shortly after that, the controller advised the flight that the visibility had dropped to 1.75 miles (2.8 km) and that the United States Weather Bureau was checking the ceiling.

Two minutes later, the controller gave a weather update to the flight, which included a measured ceiling of only 200 feet (61 m), visibility 1.75 miles (2.8 km) and very light drizzle and fog.

[3]: 2  At one minute after midnight on January 6, the aircraft crashed into a hillside west of Owasso, Oklahoma, 3.6 miles (5.8 km) north of the approach end of the runway.

[3]: 2  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 feet (160 m) from the initial point of impact.

[9] Meanwhile, the air traffic controller, having lost contact with the aircraft, notified the Oklahoma Highway Patrol that the plane was missing and asked them to check out the area near the Owasso checkpoint.

[10] After dismissing the possibility of structural failure as a cause of the crash, the fuselage of the aircraft was cut up and sold for scrap metal and American Airlines officials estimated that the wreckage would be cleared from the site by January 11.

[3]: 9  With a capacity of 40 passengers, American Airlines's Convair CV-240 fleet was used on short-haul flights, and the company placed an initial order for 100 of the aircraft in 1946, later reduced to 75.

[14] After receiving approach clearance, he said he extended the landing gear and instructed Johnson to descend at a rate of 1,000 feet (300 m) per minute.

[3]: 6  The investigation revealed that the crew had originally reported to work at Tulsa at 8:50 A.M. on January 5, and that they had been on duty for fifteen hours on the day of the crash.

[6][14] On March 7, 1957, the CAB suspended the flying permit of Captain Mims for six months, stating that even though First Officer Johnson had been flying the aircraft at the time of the crash, it was the Captain's responsibility to supervise the flight, and said that Mims had been careless in monitoring the first officer as he conducted the landing approach.

The investigators faulted the captain for his failure to notice that the aircraft had descended below the minimum safe altitude in time to prevent the crash.