Source: The Standard Author: Timothy Chui 07/31/2008
Subject Concerned: Aircraft Opinion Airlines
Maintenance lapses or management oversights are likely to be behind a string of incidents involving Boeing passenger planes over the past six days, according to an aeronautics expert.
In the latest Hong Kong-related incident, bits fell off a Cathay Pacific jetliner as it approached Vancouver. No one was hurt.
Associate professor Huang Lixi, who heads the aeronautics stream of Hong Kong University's department of mechanical engineering, said: "The 747s and 737s have been flying for decades, which suggests the faults are partly related to maintenance rather than a design or construction issues."
A Boeing spokesman said mechanical failures were not unusual as parts invariably wear out.
On July 30, the engine of a Boeing 777 operated by Vietnam Airlines out of Ho Chi Minh City caught fire after landing at Tokyo's Narita International Airport. Its 277 passengers and crew had already disembarked.
In the Cathay incident, a Boeing 747-400 from New York to Hong Kong with 380 passengers on board landed safely in Vancouver on July 29 after a mid-air incident.
Cathay said the crew heard a noise at 20,000 feet after leaving New York and later discovered that an air-conditioning access panel had detached from the aircraft causing minor damage to other parts of the fuselage.
"The fiber-glass skin panel is a secondary structure which has nothing to do with structural integrity. The event had no impact on the operation of the aircraft," Cathay said.
The regional manager of Canada's Transport Safety Board, Bill Yearwood, said a panel covering the plane's air-conditioning units had become detached and is missing.
A Cathay spokeswoman said the 16-year-old jumbo jet had last completed comprehensive mechanical reviews in March and this month.
Alternative flights had been arranged for passengers, she said.
Hong Kong's Civil Aviation Department has been notified and an investigation has been launched.
The plane is grounded pending the arrival of spare parts.
Within 24 hours of the Cathay incident in Vancouver, a Delta Air Lines' Boeing 737-800 carrying 167 people made an emergency landing at John F Kennedy International Airport in New York hours after it had blown a tire on take-off.
Three Australian passenger jets have also been involved in emergency landings over the last few days.
A Boeing 737 operated by Qantas was forced to return on July 28 when landing gear doors in the nose failed to retract.
On July 25, a Qantas Boeing 747-400 from Hong Kong with 365 passengers and crew made an emergency landing in Manila after an explosion ripped a three-meter hole in the fuselage. On July 30, investigators confirmed an oxygen cylinder exploded in the hold.
On July 27, another Qantas flight involving a Boeing 737 had to be towed from the runway after touchdown at Sydney due to a hydraulics failure.