United Airlines Flight 389 crash remembered six decades after Lake Michigan tragedy

"Last radio communications with the flight were at 21:19 when the crew were told to maintain 6000 feet and that ILS approaches were in progress on runway 14R. Shortly after this the aircraft crashed into Lake Michigan in 250 feet of water, 30 miles ENE of O'Hare Airport."

Investigators did not reach a conclusive cause for the crash. The NTSB stated it was "unable to determine the reason for the aircraft not being leveled off at its assigned altitude of 6,000 feet." Although part of the aircraft's flight data recorder was found, its contents could not be recovered.

Investigators suggested that pilot misreading of the three-pointer altimeter may have contributed to the accident. Radar data indicated that Flight 389 was already between 1,000 and 2,500 feet when instructed to descend to 6,000 feet. Three-pointer altimeters were known for being difficult to read accurately; pilots may have believed they were flying at an altitude much higher than their actual position.

This type of instrument had been implicated in other fatal accidents and was later replaced by more reliable counter-pointer and drum-pointer designs before glass cockpit technology became standard.

Flight 389 marked the first hull loss involving a Boeing 727 aircraft. The model had entered commercial service only eighteen months earlier and would go on to become one of Boeing’s most successful jetliners with over a thousand units sold. According to Aviation Safety Network data, there were a total of 120 Boeing 727 hull losses out of nearly two thousand built.

At the time of this crash, United Airlines operated around forty Boeing 727s and experienced another fatal accident involving a similar aircraft later that year.

United Airlines continues as a major full-service carrier with hubs across several U.S. airports including Chicago O'Hare International Airport.