A/C 8475 MEDA analysis
波音上海质量安全部 Boeing shanghai quality Safety department Date 2010.05
• Around 2010/05/12 AM 07:00,the PVG
mechanics gather in ramp scheduled to tow the airplane to hangar, but due to some reasons they decided to did the job of windshield replacement on ramp because they want to begin the work ASAP.
• When they replaced the new windshield they found
some different configuration between the New/Old windshield, and the new windshield has an additional wire jumper, they seek for instruction but there is noting in AMM and IPC and the tap attached in the new windshield. So they decided that let the wire jumper alone and continue the installation of windshield. During the installation they focus on the requirements of windows torque in the AMM. When they finish the installation on PM 8:00 they forgot to aware the loose cable and potential risk.
Description of AMM
• There is no other descriptions or pictures to determine the type “triplex” of the windshield in the AMM.
Description of IPC
• The IPC also haven’t other useful
descriptions about the windshield type “triplex”.
• So the mechanics think they can keep the question after install the bolt of windshields, and when they finish the work, they forgot to confirm the installation of jumper wire.
Inspection and TEST • When they completed the installation and call
the authorized signatory to do the operational test. The signatory has discover there was an additional wire jumper but he think this was an normally configuration for any special windshield configuration and he think the mechanics has completed the work entirely according AMM. unfortunately the result of test pass had increased his misconception that the installation was correct and no other problem.
Root cause and prevention measures • Perform work not according Manual and not read the •
Manual carefully. When there is something uncertainly they don’t get to the bottom of the problem, and working time is too long to let the mechanics would rather has fluke mind than to further confirm the truth of wires.
• Don’t report concerned department to get more support •
and confirm the feedback and message is suitable when there is something uncertainly. Improve the safety awareness in operation department and promote the skill of communication.