Take this only for what you consider it to be worth, after all this is only a rumour network , but I do seem to remember a China Airlines pilot receiving a memo from CAL Chief Pilot Office near the turn of the century : “Maintenance is out of control! Be careful”. As some people say “ The more things change the more they stay the same”
How to “be careful” ?
http://www.yomiuri.co.jp/dy/national...23TDY01003.htm
Maintenance error cited in jet blaze
The Yomiuri Shimbun
Joints of a fuel pipe inside the pylon holding the engine under the right wing of the China Airlines airplane that burst into flames Monday at Naha Airport were not properly secured, according to investigators.
Accident investigators believe the joints were knocked out of position when the plane landed, causing a large amount of fuel to leak and trigger an explosion.
The Construction and Transport Ministry's Aircraft and Railway Accidents Investigation Commission suspects a mistake was made during maintenance or other work on the Boeing 737-800, which underwent a regular inspection in July, and is looking into whether appropriate maintenance was carried out.
The investigators believe fuel that leaked from the pylon under the right wing was heated by the second engine causing the fuel to vaporize and ignite.
It is not thought that fuel leaked during flight, but a ground mechanic confirmed that a large volume of fuel had leaked at the aircraft parking apron, leading the investigators to believe the leak started while the airplane was moving between the runway and the taxiway.
The fuel pipes are made of metal and have a diameter of about three centimeters. They are strong enough not to rupture under high pressure and curved sections are connected using joints.
The Boeing 737-800 had such joints in several locations, held in place by metal bolts passed through rubber O-rings to prevent fuel leaking through gaps.
The thickness, material and replacement date of O-rings are clearly determined so that fuel, lubricating oil, water or other fluids does not wear away the components they protect. The component may deteriorate if the wrong type of O-ring is fitted, and it may not be possible to hold it securely in place when a thicker ring is used, since the metal bolt length becomes too short.
Aircraft always undergo a heavy impact during landing. A great deal of force is exerted on the pylons, which shake violently when planes decelerate to land.
These vibrations also affect the fuel pipes.
The accident investigators believe that before the accident, the joints on pipes that pass through the inside of the pylon came loose, making it likely the joints were jerked far out of position when the plane landed at the airport.
A China Airlines spokesman said the airline had carried out a regular inspection on the aircraft's engine in July--including an endoscopy of the inside of the combustion chamber and turbine.
The airline made another inspection--as it does every 500 flight hours--in August, but said it did not find anything wrong with the fuel pipes.
(Aug. 23, 2007)