United Airlines Flight 859 - Final Moments

Final Moments

The aircraft suffered a hydraulic failure while en-route. Preparation was made for what was expected to be a routine landing, after the crew followed the checklist for hydraulic failure. The plane touched down normally, but when the engines thrust levers were moved to the engines reverse position, the reverser buckets for the engines on the left failed to rotate to the closed position. The buckets must be closed, to direct the engine thrust to a forward direction.

That failure caused those two left-side engines to generate forward thrust, while the right-side engines generated reverse thrust. The plane immediately began to veer to the right, as a result of that asymmetrical thrust. All the tires blew out on the right main gear, after the plane left the runway and hit a new taxiway, still under construction. The nose gear collapsed, and the fuel tank on the right wing was ruptured, starting the fatal fire. The Civil Aeronautics Board (CAB) report also stated that a contributing factor was the failure of the first officer to monitor the reverse thrust indicator lights, when he applied reverse thrust.

Carbon monoxide poisoning was the cause of death for 16 of the passengers, who were not able to evacuate quickly enough. One elderly woman broke both ankles during the evacuation, and later died from shock.