China Eastern Airline Flight 583 Accident

On 6^th April 1993, McDonnell Douglas MD-11 of China Eastern Airline flight 583 made an emergency landing on Shemya Air Force Base in Alaska, US. The aircraft was operating on the Pacific Ocean at Mach 0.84 when the crew member accidentally operated slats. The deployment of slats causes severe pitch oscillation therefore pilot had no other choice than to land.

Aircraft Information

Flight information

China Easter Airline Aircraft MD-11 with registration number B-2171 was en route to Los Angeles International Airport from Hongqiao International Airport Shanghai. The total number of people in the plane was 255 of which 20 were crew members.

Captain Corrective Actions During Accident

The extension of leading edge flaps results in the pitching-up movement in the aircraft during autopilot. The pilot took corrective action and replaced the flap/slat handle in the UP/RET position. The pilot disengaged the autopilot and exert forward control column force. This resulted in an abrupt nose-down elevator command. The captain subsequently commanded elevator movement to correct the pitch attitude. During these several violent pitches, oscillations were induced that ended up

Causes of Accident

Someone in the cockpit inadvertently deploys the leading edge slats in a cruise flight. The autopilot was disconnected and the captain was manually controlling the aircraft. The deployment of slats causes violent pitch oscillation in the aircraft. Although the pilot was successful in stabilizing it he lost 5,000 feet of altitude. The captain then declared an emergency because the passengers and the crew members were injured.

Injuries Details

Two passengers were seriously injured and then later died rest of them got injuries. 60 passengers were taken to hospitals which include cockpit crew and flight attendants too. Three from the cockpit crew and 4 from the cabin crew received serious injuries. On the passenger side, 96 minors were injured and 53 were serious. On 24 April 1993, the surviving passenger was discharged from the hospital. The aircraft was in a good shape externally and did receive any damage but the passenger cabin was substantial damage. The Douglas Company reported that the cost of repairing the aircraft would be approx. $1.500.000 (1993).

Crew Details

The total number of crew was 20. The cockpit crew included a first officer, a flight engineer, and a radio operator. There were also four international flight relief cockpit crew members and 12 flight attendants.

NTSB Findings

The national transportation safety board the Douglas aircraft company’s inadequate design of flap/slat actuation handle was the cause of the accident. The UP/RET position of the handle can quickly and inadvertently deploy the slats during the cruise flight. The pilot tries to stabilize the aircraft but the associated light control force characteristic of MD-11 in cruise flight makes several violent pitch oscillations.

The lack of specific MD-11 pilot recovery training from high altitudes was also a contributing factor to the violence of pitch oscillation. For the injuries, the lack of seat restraints by the passenger and crew was the main contributing factor. (NTSB Report flight 583)

Conclusion

All the cockpit and Cabin crew were qualified for the flight even though the pilot had recently completed recurrent training.  He was fully aware of the available information regarding the inadvertent slat extensions. The aircraft was in airworthiness condition. There was also no sign was turbulence or engine deficiency that would cause the accident. Only the flap/slat handle design and operation were considered to be impropriated. The captain affords to stabilize the aircraft and ends up losing 5,000 feet of altitude. The severe pitch oscillation in the aircraft causes injuries to the passengers and the cabin crew. The pilot makes an emergency landing on US Air force Base, Shemya Alaska. The captain successfully landed the plane. (Planespotters.net photo)

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