As a result of this occurrence, the operator raised an
Engineering Instruction (EI), EI-767-032-0102 Rev 0, to immediately
inspect all B767 MLG shock strut doors and check the torque values
of the door attaching hardware. All of the operator's B767 aircraft
were subsequently checked between 23 November 2001 and 8 December
2001. The inspection revealed that a number of MLG shock strut door
mounting bolts were found to be below the required Aircraft
Maintenance Manual (AMM) torque value and were retorqued to the
correct value. As a result of the EI inspection, the operator
subsequently issued a revised EI (EI-767-032-0102 Rev 1) requiring
that the inspection be conducted on a regular basis; every 3
months.
As a result of reports of loose or fractured MLG shock strut
door attach bolts, the aircraft manufacturer developed an
engineering change to prevent the MLG shock strut door attach bolts
from loosening and indicated that a Service Bulletin to incorporate
those changes would be released in the second quarter of 2002.
As there have been two similar events on Australian registered
aircraft, The Australian Transport Safety Bureau will continue to
monitor actions relating to B767 MLG shock strut door separation
occurrences pending the release of the Service Bulletin.