Incident
The aircraft, a DC-8, departed Shanghai-Hongqiao Airport at 1357LT on a flight to Tokyo, Japan. On board were 113 passengers and 11 crew members, totaling 124 occupants. Nine minutes after takeoff, the crew heard a strange noise from the lower middle part of the aircraft. This was immediately followed by a series of warnings: a hydraulic low level warning, a hydraulic reservoir air low pressure warning, a complete loss of hydraulic system pressure, abnormal flap position indications, and a complete loss of air brake pressure.
Emergency Landing
Faced with the hydraulic system failure, the crew decided to return to Shanghai for an emergency landing. The aircraft touched down fast on runway 36. It overran the runway and came to rest in a drainage ditch adjacent to the runway.
Evacuation and Injuries
All 124 occupants were evacuated from the aircraft. Twenty-three of them sustained injuries during the incident.
Probable Cause
The official investigation determined the probable cause: the explosion of the air brake bottle damaged 13 hydraulic system tubes and 2 emergency air brake system tubes. Some of these damages resulted in the failure of extension of flaps and a loss of normal as well as emergency wheel braking. This increased the roll after touchdown distance to a value greater than the available runway and stop way length. These factors prevented the captain from stopping the aircraft within the runway and stop way confines.