China Airlines Flight 006
Encyclopedia
China Airlines
Flight 006 (callsign "Dynasty 006") was a daily non-stop flight departing from Taipei
at 16:15 and scheduled to arrive at Los Angeles International Airport
at 07:00 local time. On February 19, 1985, it was involved in an aircraft upset accident after the No. 4 engine flamed out
. The plane rolled over and plunged 30000 ft (9,144 m), experiencing high speeds and g-force
s (approaching 5g) before the captain was finally able to recover from the rapid dive, and then to divert to San Francisco International Airport
.
was 350 miles (550 km) northwest of San Francisco, cruising at an altitude of 41000 ft (12,496.8 m). The flight crew consisted of captain Min-Yuan Ho, first officer Ju Yu Chang, flight engineer Kuo-Win Pei, relief captain Chien-Yuan Liao, and relief flight engineer Shih Lung Suwere. The sequence began when the No. 4 starboard outermost engine stalled at a low thrust setting and flamed out. That engine had failed twice during previous flights (both while cruising at FL
410 & 430, respectively). In each of those cases, the engine was restarted, after descending to a lower altitude. The maintenance response to the logbook entries that noted the problems were: engine inspection; fuel filter drainage and replacement; vane controller inspection and replacement; water drainage from Mach probes; insufficient modules; and other filter replacements. None of those acts fixed the recurrent stalling and flameout problem of the No. 4 engine.
After the flameout, the captain instructed the flight engineer to attempt to restart the engine, while the plane remained at FL
410 (nominally 41,000 feet at a standard altimeter setting which does not reflect actual pressure, and is used by all aircraft above 18,000 feet), with the autopilot still engaged. That was contrary to the flight manual procedure, which required the plane to be below 30000 feet (9,144 m), before attempting to restart a flamed out engine. The restart attempt failed.
The airspeed continued to decrease, while the autopilot rolled the control wheel to the maximum left limit of 23 degrees. As the speed decreased even further, the plane began to roll to the right, even though the AP was maintaining the maximum left roll limit of 23 degrees. By the time the captain disconnected the autopilot, the plane had rolled over 60 degrees to the right and the nose began to drop. Aileron
control was the only means available to the autopilot to keep the wings level as the autopilot does not connect to the rudder during normal cruise flight. To counteract the asymmetrical forces created by the loss of thrust from the No. 4 engine, it was essential for the pilot to manually push on the left rudder. However, the captain failed to use any rudder inputs at all, before or after disconnecting the AP. The resulting uncontrolled flight path is depicted in the diagram to the left.
As the plane descended through clouds, the Captain's attention was drawn to the artificial horizon
which displayed excessive bank and pitch. Because such an attitude is highly irregular, the crew incorrectly assumed the indicators to be faulty. Without any visuals references (due to the clouds around the aircraft) and having discarded the information from the ATIs, the crew became spatially disoriented
. The plane entered a steep dive at a high bank angle. Altitude decreased 10000 ft (3,048 m) within only 20 seconds, a vertical descent averaging 340.9 mph. The crew and passengers experienced g-forces
reaching as much as 5g.
Only after breaking through the bottom of the clouds at 11000 feet (3,352.8 m) could the captain orient himself and bring the plane under control, leveling out at 9600 feet (2,926.1 m). They had descended 30000 ft (9,144 m) in under two and a half minutes. The flight crew were under the impression that all four engines had flamed out, but the National Transportation Safety Board
believes only engine No. 4 had failed. After leveling out, it was found that the three remaining engines (1, 2 & 3 as numbered from left to right looking forward from the cockpit) were supplying normal thrust. A restart attempt brought No. 4 back into use. They began climbing and reported to air traffic control
"condition normal now" and they were continuing on to Los Angeles. They then noticed that the inboard main landing gear were down and one of the plane's hydraulic systems was empty. Because they didn't have sufficient fuel to reach Los Angeles with the drag added by the landing gear, they diverted to San Francisco. Learning there were injured people on board, an emergency was declared and they flew straight in to the airport and landed without further incident.
There were two serious injuries on board: a fracture and laceration of a foot; and an acute back strain requiring two days of hospitalization. The aircraft was significantly damaged by the aerodynamic forces. The wings were permanently bent upwards by two inches, the inboard main landing gear lost two actuator doors, and the two inboard main gear struts were left dangling. Most affected was the tail, where large outer parts of both horizontal stabilizers had been ripped off. The entire left outboard elevator
had been lost along with its actuator
, which had been powered by the hydraulic system that ruptured and drained.
After substantial investigation, this accident brought to international attention the problem of jet lag
as a contributing factor to pilot error
s. The captain was considered to be highly experienced and had flown six international flights in the previous two weeks. Though he testified that he did not believe he was tired, NTSB investigators suggest that his inability to sleep during his rest period and the fact that the accident took place at 2 am Taipei time contributed to his inability to focus on and process important details about the aircraft's behavior that could have averted the accident.
After repairs were made to correct the significant damage to the plane, it returned to service on April 25, 1985. It continued in service for nearly 12 years until it was leased to China Airlines' sister company, Mandarin Airlines
, on January 1, 1997. Later, it was owned and operated by a religious organization known as Gospel to the Unreached Millions or GUM headed by K. A. Paul and christened 'Global Peace One'. On July 17, 2005 the FAA suspended its operating certificate due to insufficient maintenance. It was then due major maintenance work, but was never completed. , the aircraft is kept in a large hangar at General Abelardo L. Rodríguez International Airport
, in Tijuana
, Baja California
and it is possible that the aircraft will be scrapped as it is reported to be in very poor condition. The aircraft can be seen using Google Earth
at the coordinates 32°32'38.42"N 116°57'56.10"W.
The flight was documented on the television program Mayday
(otherwise known as Air Emergency or Air Crash Investigation).
China Airlines continues to operate Flight 6 from Taipei to Los Angeles.
China Airlines
China Airlines is both the flag carrier and the largest airline of Republic of China . Although not directly state-owned, the airline is owned by China Airlines Group, which is owned by the China Aviation Development Foundation...
Flight 006 (callsign "Dynasty 006") was a daily non-stop flight departing from Taipei
Taipei
Taipei City is the capital of the Republic of China and the central city of the largest metropolitan area of Taiwan. Situated at the northern tip of the island, Taipei is located on the Tamsui River, and is about 25 km southwest of Keelung, its port on the Pacific Ocean...
at 16:15 and scheduled to arrive at Los Angeles International Airport
Los Angeles International Airport
Los Angeles International Airport is the primary airport serving the Greater Los Angeles Area, the second-most populated metropolitan area in the United States. It is most often referred to by its IATA airport code LAX, with the letters pronounced individually...
at 07:00 local time. On February 19, 1985, it was involved in an aircraft upset accident after the No. 4 engine flamed out
Flameout
A flameout refers to the failure of a jet engine caused by the extinction of the flame in the combustion chamber. It can be caused by a number of factors, including fuel exhaustion; compressor stall; insufficient oxygen supply; foreign object damage ; severe inclement weather; and mechanical...
. The plane rolled over and plunged 30000 ft (9,144 m), experiencing high speeds and g-force
G-force
The g-force associated with an object is its acceleration relative to free-fall. This acceleration experienced by an object is due to the vector sum of non-gravitational forces acting on an object free to move. The accelerations that are not produced by gravity are termed proper accelerations, and...
s (approaching 5g) before the captain was finally able to recover from the rapid dive, and then to divert to San Francisco International Airport
San Francisco International Airport
San Francisco International Airport is a major international airport located south of downtown San Francisco, California, United States, near the cities of Millbrae and San Bruno in unincorporated San Mateo County. It is often referred to as SFO...
.
Accident
The accident occurred ten hours into the regular service between Taipei and Los Angeles. The Boeing 747SP-09Boeing 747SP
The Boeing 747SP is a modified version of the Boeing 747 jet airliner which was designed for ultra-long-range flights. The SP stands for "Special Performance". Compared with its predecessor, the 747-100, the 747SP retains its wide-body, four-engine layout, along with its double-deck design, but...
was 350 miles (550 km) northwest of San Francisco, cruising at an altitude of 41000 ft (12,496.8 m). The flight crew consisted of captain Min-Yuan Ho, first officer Ju Yu Chang, flight engineer Kuo-Win Pei, relief captain Chien-Yuan Liao, and relief flight engineer Shih Lung Suwere. The sequence began when the No. 4 starboard outermost engine stalled at a low thrust setting and flamed out. That engine had failed twice during previous flights (both while cruising at FL
Flight level
A Flight Level is a standard nominal altitude of an aircraft, in hundreds of feet. This altitude is calculated from the International standard pressure datum of 1013.25 hPa , the average sea-level pressure, and therefore is not necessarily the same as the aircraft's true altitude either...
410 & 430, respectively). In each of those cases, the engine was restarted, after descending to a lower altitude. The maintenance response to the logbook entries that noted the problems were: engine inspection; fuel filter drainage and replacement; vane controller inspection and replacement; water drainage from Mach probes; insufficient modules; and other filter replacements. None of those acts fixed the recurrent stalling and flameout problem of the No. 4 engine.
Flight level
A Flight Level is a standard nominal altitude of an aircraft, in hundreds of feet. This altitude is calculated from the International standard pressure datum of 1013.25 hPa , the average sea-level pressure, and therefore is not necessarily the same as the aircraft's true altitude either...
410 (nominally 41,000 feet at a standard altimeter setting which does not reflect actual pressure, and is used by all aircraft above 18,000 feet), with the autopilot still engaged. That was contrary to the flight manual procedure, which required the plane to be below 30000 feet (9,144 m), before attempting to restart a flamed out engine. The restart attempt failed.
The airspeed continued to decrease, while the autopilot rolled the control wheel to the maximum left limit of 23 degrees. As the speed decreased even further, the plane began to roll to the right, even though the AP was maintaining the maximum left roll limit of 23 degrees. By the time the captain disconnected the autopilot, the plane had rolled over 60 degrees to the right and the nose began to drop. Aileron
Aileron
Ailerons are hinged flight control surfaces attached to the trailing edge of the wing of a fixed-wing aircraft. The ailerons are used to control the aircraft in roll, which results in a change in heading due to the tilting of the lift vector...
control was the only means available to the autopilot to keep the wings level as the autopilot does not connect to the rudder during normal cruise flight. To counteract the asymmetrical forces created by the loss of thrust from the No. 4 engine, it was essential for the pilot to manually push on the left rudder. However, the captain failed to use any rudder inputs at all, before or after disconnecting the AP. The resulting uncontrolled flight path is depicted in the diagram to the left.
As the plane descended through clouds, the Captain's attention was drawn to the artificial horizon
Attitude indicator
An attitude indicator , also known as gyro horizon or artificial horizon, is an instrument used in an aircraft to inform the pilot of the orientation of the aircraft relative to earth. It indicates pitch and bank or roll and is a primary instrument for flight in instrument meteorological conditions...
which displayed excessive bank and pitch. Because such an attitude is highly irregular, the crew incorrectly assumed the indicators to be faulty. Without any visuals references (due to the clouds around the aircraft) and having discarded the information from the ATIs, the crew became spatially disoriented
Spatial disorientation
Spatial disorientation is the inability to correctly interpret aircraft attitude, altitude or airspeed, in relation to the Earth or point of reference. Spatial disorientation is a condition in which an aircraft pilot's perception of direction does not agree with reality...
. The plane entered a steep dive at a high bank angle. Altitude decreased 10000 ft (3,048 m) within only 20 seconds, a vertical descent averaging 340.9 mph. The crew and passengers experienced g-forces
G-force
The g-force associated with an object is its acceleration relative to free-fall. This acceleration experienced by an object is due to the vector sum of non-gravitational forces acting on an object free to move. The accelerations that are not produced by gravity are termed proper accelerations, and...
reaching as much as 5g.
Only after breaking through the bottom of the clouds at 11000 feet (3,352.8 m) could the captain orient himself and bring the plane under control, leveling out at 9600 feet (2,926.1 m). They had descended 30000 ft (9,144 m) in under two and a half minutes. The flight crew were under the impression that all four engines had flamed out, but the National Transportation Safety Board
National Transportation Safety Board
The National Transportation Safety Board is an independent U.S. government investigative agency responsible for civil transportation accident investigation. In this role, the NTSB investigates and reports on aviation accidents and incidents, certain types of highway crashes, ship and marine...
believes only engine No. 4 had failed. After leveling out, it was found that the three remaining engines (1, 2 & 3 as numbered from left to right looking forward from the cockpit) were supplying normal thrust. A restart attempt brought No. 4 back into use. They began climbing and reported to air traffic control
Air traffic control
Air traffic control is a service provided by ground-based controllers who direct aircraft on the ground and in the air. The primary purpose of ATC systems worldwide is to separate aircraft to prevent collisions, to organize and expedite the flow of traffic, and to provide information and other...
"condition normal now" and they were continuing on to Los Angeles. They then noticed that the inboard main landing gear were down and one of the plane's hydraulic systems was empty. Because they didn't have sufficient fuel to reach Los Angeles with the drag added by the landing gear, they diverted to San Francisco. Learning there were injured people on board, an emergency was declared and they flew straight in to the airport and landed without further incident.
Aftermath
Elevator (aircraft)
Elevators are flight control surfaces, usually at the rear of an aircraft, which control the aircraft's orientation by changing the pitch of the aircraft, and so also the angle of attack of the wing. In simplified terms, they make the aircraft nose-up or nose-down...
had been lost along with its actuator
Actuator
An actuator is a type of motor for moving or controlling a mechanism or system. It is operated by a source of energy, usually in the form of an electric current, hydraulic fluid pressure or pneumatic pressure, and converts that energy into some kind of motion. An actuator is the mechanism by which...
, which had been powered by the hydraulic system that ruptured and drained.
After substantial investigation, this accident brought to international attention the problem of jet lag
Jet lag
Jet lag, medically referred to as desynchronosis, is a physiological condition which results from alterations to the body's circadian rhythms; it is classified as one of the circadian rhythm sleep disorders...
as a contributing factor to pilot error
Pilot error
Pilot error is a term used to describe the cause of an accident involving an airworthy aircraft where the pilot is considered to be principally or partially responsible...
s. The captain was considered to be highly experienced and had flown six international flights in the previous two weeks. Though he testified that he did not believe he was tired, NTSB investigators suggest that his inability to sleep during his rest period and the fact that the accident took place at 2 am Taipei time contributed to his inability to focus on and process important details about the aircraft's behavior that could have averted the accident.
After repairs were made to correct the significant damage to the plane, it returned to service on April 25, 1985. It continued in service for nearly 12 years until it was leased to China Airlines' sister company, Mandarin Airlines
Mandarin Airlines
Mandarin Airlines, Limited is an airline based in Songshan District, Taipei, Taiwan. The Republic of China-based airline is China Airlines' regional and domestic subsidiary. It also operates charter services...
, on January 1, 1997. Later, it was owned and operated by a religious organization known as Gospel to the Unreached Millions or GUM headed by K. A. Paul and christened 'Global Peace One'. On July 17, 2005 the FAA suspended its operating certificate due to insufficient maintenance. It was then due major maintenance work, but was never completed. , the aircraft is kept in a large hangar at General Abelardo L. Rodríguez International Airport
General Abelardo L. Rodríguez International Airport
Tijuana International Airport , sometimes referred to as General Abelardo L. Rodríguez International Airport, in Tijuana, Baja California, Mexico, is Mexico's second northernmost airport after Mexicali International Airport...
, in Tijuana
Tijuana
Tijuana is the largest city on the Baja California Peninsula and center of the Tijuana metropolitan area, part of the international San Diego–Tijuana metropolitan area. An industrial and financial center of Mexico, Tijuana exerts a strong influence on economics, education, culture, art, and politics...
, Baja California
Baja California
Baja California officially Estado Libre y Soberano de Baja California is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is both the northernmost and westernmost state of Mexico. Before becoming a state in 1953, the area was known as the North...
and it is possible that the aircraft will be scrapped as it is reported to be in very poor condition. The aircraft can be seen using Google Earth
Google Earth
Google Earth is a virtual globe, map and geographical information program that was originally called EarthViewer 3D, and was created by Keyhole, Inc, a Central Intelligence Agency funded company acquired by Google in 2004 . It maps the Earth by the superimposition of images obtained from satellite...
at the coordinates 32°32'38.42"N 116°57'56.10"W.
The flight was documented on the television program Mayday
Mayday (TV series)
Mayday, also known as Air Crash Investigation in the United Kingdom, Australia and Asia and Air Emergency and Air Disasters in the United States, is a Canadian documentary television programme produced by Cineflix investigating air crashes, near-crashes and other disasters...
(otherwise known as Air Emergency or Air Crash Investigation).
China Airlines continues to operate Flight 6 from Taipei to Los Angeles.
External links
- Accident Brief by the U.S. National Transportation Safety Board.
- Full Accident Report by the U.S. National Transportation Safety Board.
- Summary and comments in Risks Digest.
- Time Magazine story
- German article with pictures of the damaged airplane after landing in Der Spiegel.