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China Airlines Flight 006 (callsign "Dynasty 006") is a daily non-stop flight from Taipei to Los Angeles International Airport. On February 19, 1985, the Boeing 747SP operating the flight was involved in an aircraft upset accident after the No. 4 engine flamed out. The plane rolled over and plunged , experiencing high speeds and g-forces (approaching 5g) before the captain was able to recover from the rapid dive, and then to divert to San Francisco International Airport.〔 ==Incident== The accident occurred ten hours into the service that departed Taipei at 16:15. The Boeing 747SP-09 was 350 miles (550 km) northwest of San Francisco, cruising at an altitude of . The flight was in the hands of a seasoned crew, consisting of Captain Min-Yuan Ho (55), First Officer Ju Yu Chang (53), Flight Engineer Kuo-Win Pei (55), Relief Captain Chien-Yuan Liao (53), and Relief Flight Engineer Po-Chae Su Shih Lung (41).〔 Captain Ho was a highly experienced pilot with approximately 15,500 flight hours. The first officer was also experienced, with more than 7,700 hours to his credit, and the flight engineer, like the captain, had approximately 15,500 hours of flight time.〔http://www.airdisaster.com/reports/ntsb/AAR86-03.pdf〕 The incident occurred while the main crew was on duty. 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 (while cruising at FL 410 and 430). 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 included 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.〔(NTSB ) report courtesy of University of Bielefeld - Faculty of technology html version by Hiroshi Sogame Safety Promotion Comt. All Nippon Airways〕〔(【引用サイトリンク】title=Production List )〕 After the flameout, the captain instructed the flight engineer to attempt to restart the engine, while the plane remained at FL 410 (41,000 feet) with the autopilot still engaged and the bleed air on. This was contrary to the flight manual procedure, which required the plane to be below before any attempt to restart a flamed-out engine. The 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 autopilot was maintaining the maximum left roll limit. By the time the captain disconnected the autopilot, the plane had rolled over 60 degrees to the right and the nose had begun 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 autopilot. The resulting uncontrolled flight path is depicted in the diagram. 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 visual references (due to the clouds) and having rejected the information from the ADIs, the crew became spatially disoriented. The plane entered a steep dive at a high bank angle. Altitude decreased within only 20 seconds, a vertical descent averaging . The crew and passengers experienced g-forces reaching as much as 5g.〔 Only after breaking through the bottom of the clouds at did the captain orient himself and bring the plane under control, leveling out at . They had descended 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 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 was down〔 and one of the plane's hydraulic systems was empty. Because they did not 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. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「China Airlines Flight 006」の詳細全文を読む スポンサード リンク
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