What happened
On March 18, 1989, a McDonnell Douglas DC-9 aircraft registered as N310EG was operating a cargo mission for the Air Force Logair program. The flight, designated as Evergreen International Airlines Flight 17 (4U17/EIA17), departed from Kelly Air Force Base with an intermediate stop planned at Carswell Air Force Base in Fort Worth, Texas, before proceeding to Tinker Air Force Base.
The aircraft carried only two crew members: the captain and the first officer. Shortly after departing from its stop at Carswell AFB, the main cargo door unexpectedly opened during flight. This sudden event caused a rapid decompression and loss of control over the aircraft's pitch and stability. Despite the crew's efforts to manage the emergency and attempt a landing, the situation became unmanageable, leading to the crash of the aircraft.
Investigation
The investigation into the accident focused on the mechanical failure of the cargo door mechanism. It was determined that the door opened in flight due to a defect in the locking system, which failed to secure the door properly despite being closed. The crew's inability to regain control stemmed from the aerodynamic instability caused by the open door.
Findings
The primary contributing factor to the accident was the failure of the main cargo door to remain locked during flight. This mechanical defect led directly to the loss of aircraft control and the subsequent crash. Both pilots were killed in the incident, with no survivors among the occupants.