Maintenance Powerplant; Maintenance Airframe
Maintenance Technician 15
Situational Awareness
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy
Human Factors
I was asked to supervise and show two mechanics how to properly install a number 8 main landing gear tire on a Boeing 767-300 aircraft. I showed the [mechanics] how to properly look up in the aircraft maintenance manual (AMM) the procedures and tooling required and read through the AMM with them while a tire was being procured by our lead. I assisted the two [mechanics] in the process of removing and replacing the wheel assembly but failed to check the part number of the tire being installed. Having worked international line maintenance before; I am aware of the part number differences between the B767-300 and the B767-300ER tires. I feel that the distraction of training the two students; and assuming the lead AMT was providing me with the proper effective tire for the aircraft; distracted me from checking the part effectivity for myself. Then when entering the information into the log I again overlooked the fact that the wrong Part Number (PN) had been installed onto the aircraft. Though the incorrect tire was provided for me; ultimately I am responsible for the equipment that is being installed and signed for. I supervised and help[ed] perform the maintenance task; and signed off the aircraft maintenance log. I was unaware of my mistake until [about a month later] I was made aware of the discrepancy by the hangar shift manager and my lead; and was informed that the tracking system had logged the error in part effectivity and that I needed to sit and make a statement for the internal investigation into the matter. I brought my error to the attention of the two [mechanics] that I was training and emphasized the importance of checking PN effectivity with the aircraft that is being worked; regardless of who provides the part for them. I also explained that ultimately regardless of the situation; the mechanic performing and signing for the work is responsible for insuring the airworthiness and effectivity of the part being installed on the aircraft.
During a B767-300ER Service Check an incorrect wheel assembly was installed on the Main Landing Gear. A wheel assembly for a B767-300 non-ER was used.