Elevator control concerns spark Boeing safety checks
Aviation authorities have ordered safety checks on 160 Boeing 737 airliners flying on the mainland because of potential problems with their elevator controls.
The General Administration of Civil Aviation said on its website yesterday that some 737 models needed to have their tail's elevator control mechanisms examined.
Liu Jiangtao, an aircraft maintenance technician with China Southern Airlines, said that if the bearing under the elevator control mechanism loosened, unexpected vibration could make it hard to control the aircraft and affect its structural integrity.
The administration statement clarified a media report earlier yesterday that said safety hazards had been identified in 400 Boeing 737s on the mainland following the discovery by the US Federal Aviation Administration of extensive damage in the left elevator of a B737-800 operated by Irish budget airline Ryanair on March 2. The FAA ordered inspections for 600 B737 aircraft in the United States last Friday.
Boeing China's communications director, Wang Yukui, said Boeing issued an all-operator message last Wednesday advising operators to inspect the elevator tab control mechanism on 'next-generation' 737s.
The civil aviation administration said yesterday that it issued the same directive on Monday.
According to baidu.com, there are more than 600 Boeing 737s in operation on the mainland, so the administration's examination order covers roughly a quarter of the them.
Air China said it fixed a mechanical problem on one of its 737s after receiving the emergency airworthiness directive from the regulator and the aircraft now complied with airworthiness requirements.
Wu Yunzeng, a ground crew member at Shenzhen Airlines, said: 'We have received the directive and have started the examination. The work is almost done now.'
He said the planes would continue to fly as scheduled.
Wu said Shenzhen Airlines had eight 737s, and they accounted for a seventh of its fleet.
The 737 is used for short- and medium-haul flights. Nearly every major airline in China operates them, including Air China, China Southern Airlines, China Eastern Airlines, Hainan Airlines and Shanghai Airlines.
In June last year, 736 Boeing planes were flying on the mainland, accounting for 53 per cent of all civil aircraft in use.
In Hong Kong, eight Boeing 737-300 and Boeing 737-800 aircraft operated by Hong Kong Airlines and Hong Kong Express Airways will require inspection before March 24 to ensure that their horizontal tails are mechanically sound, a spokesman for the Hong Kong Civil Aviation Department said.
It also said that 33 Boeing 777s operated by Cathay Pacific Airways needed the software that controls the auto-pilot during take-off replaced by the end of next month.
In the meantime, the affected aircraft could continue in service because the auto-pilot function was seldom used when an aircraft was taking off.