Narrative:

A B767-300 aircraft arrived at an international gate around xa:40am. It was scheduled to depart to ZZZZ at xb:45pm. In addition to the required checks; it had a corrective action required for a left nose tire being worn to limits. There was also an in-flight shutdown and chip detector inspection due on the number two engine. Myself and another amt (aviation maintenance technician) were assigned to work the aircraft. Upon arrival at the aircraft; I found the right nose tire was also worn to limits. We also found the crew O2 oxygen below allowable limits during the check. We worked the required daily check and pre-departure check before starting the tire replacement. By this time; we had another amt (aviation maintenance technician) on site. He had brought another tire over to save us time for returning to the line to get another tire. I had the maintenance manual for the removal and installation of the nose tire in hand. All three amts were aware of the importance of the nose wheel spacer installation. We were well aware that there were several recent occurrences where the spacer was left off the tire. We began to replace both nose tires. I proceeded to remove the lockbolts and loosen the axle nut of the right nose tire. In order to expedite the removal and installation of two tires; I proceeded to remove the bolts and axle nut of the left tire while the other two amts proceeded to remove and install the right tire. I had thought that the other amts had checked for the installation of the spacer after installing the tire and axle nut. When I had finished with the removal of the axle nut on the left tire; we switched off; and I proceeded to torque the axle nut of the right tire while the left tire was being installed. After torquing the axle nut; I checked to make sure that not more than one thread was showing [on the axle]; and there was not more than one thread showing. I thought checking the number of threads showing was a good double checking procedure to make certain that the spacer was installed. If the spacer was not installed; I thought there would be 3-4 axle threads showing after proper torquing. Then I shook the tire to make sure that it did not wobble. It did not wobble. I proceeded to the left tire to torque the axle nut repeating the same procedure as before. We then proceeded to work the other time items. Somehow even with the training and awareness of the necessity of the nose tire spacer; all three amts missed installation of the nose wheel spacer (axle nut washer) called out by the maintenance manual. Apparently the other amts had checked for the presence of the inner spacer but not the outer spacer (washer). I assumed they knew to check for the outer spacer (washer) and in the end I failed to check for it [also]. At approximately xc:00pm I was made aware of the subsequent finding of the wheel spacers (washers) being found missing; it was not until this time that I was aware of any issues. The wheel shop had discovered the spacers (washers) on the old wheels; and they notified the appropriate people. The nose wheels were replaced with no effect to aircraft safety. I believe that if the nose wheel spacer was painted or somehow marked with a highly visible color such as red; orange; or yellow; that it would prevent this occurrence from happening again.

Related reports:

Google
 

Original NASA ASRS Text

Title: A Line Mechanic reports he and two other AMTs (Aviation Maintenance Technicians) failed to reinstall the axle nut washer on both nose tires of a B767-300 aircraft. Their Wheel Shop mechanics noticed the washers stuck to the old removed wheel halves.

Narrative: A B767-300 aircraft arrived at an international gate around XA:40am. It was scheduled to depart to ZZZZ at XB:45pm. In addition to the required checks; it had a corrective action required for a left nose tire being worn to limits. There was also an in-flight shutdown and chip detector inspection due on the Number two engine. Myself and another AMT (Aviation Maintenance Technician) were assigned to work the aircraft. Upon arrival at the aircraft; I found the right nose tire was also worn to limits. We also found the crew O2 oxygen below allowable limits during the Check. We worked the required daily Check and pre-departure Check before starting the tire replacement. By this time; we had another AMT (Aviation Maintenance Technician) on site. He had brought another tire over to save us time for returning to the line to get another tire. I had the Maintenance Manual for the removal and installation of the nose tire in hand. All three AMTs were aware of the importance of the nose wheel spacer installation. We were well aware that there were several recent occurrences where the spacer was left off the tire. We began to replace both nose tires. I proceeded to remove the lockbolts and loosen the axle nut of the right nose tire. In order to expedite the removal and installation of two tires; I proceeded to remove the bolts and axle nut of the left tire while the other two AMTs proceeded to remove and install the right tire. I had thought that the other AMTs had checked for the installation of the spacer after installing the tire and axle nut. When I had finished with the removal of the axle nut on the left tire; we switched off; and I proceeded to torque the axle nut of the right tire while the left tire was being installed. After torquing the axle nut; I checked to make sure that not more than one thread was showing [on the axle]; and there was not more than one thread showing. I thought checking the number of threads showing was a good double checking procedure to make certain that the spacer was installed. If the spacer was not installed; I thought there would be 3-4 axle threads showing after proper torquing. Then I shook the tire to make sure that it did not wobble. It did not wobble. I proceeded to the left tire to torque the axle nut repeating the same procedure as before. We then proceeded to work the other time items. Somehow even with the training and awareness of the necessity of the nose tire spacer; all three AMTs missed installation of the nose wheel spacer (axle nut washer) called out by the Maintenance Manual. Apparently the other AMTs had checked for the presence of the inner spacer but not the outer spacer (washer). I assumed they knew to check for the outer spacer (washer) and in the end I failed to check for it [also]. At approximately XC:00pm I was made aware of the subsequent finding of the wheel spacers (washers) being found missing; it was not until this time that I was aware of any issues. The Wheel Shop had discovered the spacers (washers) on the old wheels; and they notified the appropriate people. The nose wheels were replaced with no effect to aircraft safety. I believe that if the nose wheel spacer was painted or somehow marked with a highly visible color such as red; orange; or yellow; that it would prevent this occurrence from happening again.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.