some idiot chinese was smuggling something like a bulgogi gas bottle onto the plane, like the sausages and bats ears shark fins and unpasteurised hoof and mouth disease offal and duck feet and rhino pizzles and all the other stuff they always trying to smuggle in.
A bomb ? No . Would have worked better.
Rust ? No. Aluminimum does not rust.
Bad maintainence ? No. Aircraft structural components require inspection but not maintenance. 747 does not have a record of structural failure. These planes are not really "old".
