Narrative:

During the course of an engine fan blade lube, hub re-torque, and fan balance, a step on the work card was missed by accident. The step that was missed was the step which instructs you to inspect and remove any temporary markings placed on the fan blades. Temporary marks were placed on the fan blades with an approved marker and were not removed. Over the course of the maintenance being performed, there were a few things that were not working to our advantage. Throughout the course of the night, a storm had moved in with heavy rain and dropping temperatures. While installing the fan blades and spinner, I forgot to remove the temporary marks that were placed on the blades by another shift with a marker. There are various steps prior to this step under the same signature block detailing the installation of the front cone. I was so involved with the installation and torque of the front cone, I forgot to rub the marks off the blades and cannot blame anyone but myself. I believe that a combination of factors were involved with overlooking this step. 1) WX, 2) concentrating on the installation of the fan blades and the spinner, and 3) the fact that under the steps I was performing, the blades were not involved yet a sub-step references you from the front cone and then backtracks to the fan blades which are not involved with the installation currently at hand.

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Original NASA ASRS Text

Title: A B737 TECHNICIAN RPTS THAT DURING AN ENG FAN BLADE LUBRICATION, THE JOB CARD STEP TO REMOVE ALL TEMPORARY BLADE MARKINGS WAS MISSED.

Narrative: DURING THE COURSE OF AN ENG FAN BLADE LUBE, HUB RE-TORQUE, AND FAN BAL, A STEP ON THE WORK CARD WAS MISSED BY ACCIDENT. THE STEP THAT WAS MISSED WAS THE STEP WHICH INSTRUCTS YOU TO INSPECT AND REMOVE ANY TEMPORARY MARKINGS PLACED ON THE FAN BLADES. TEMPORARY MARKS WERE PLACED ON THE FAN BLADES WITH AN APPROVED MARKER AND WERE NOT REMOVED. OVER THE COURSE OF THE MAINT BEING PERFORMED, THERE WERE A FEW THINGS THAT WERE NOT WORKING TO OUR ADVANTAGE. THROUGHOUT THE COURSE OF THE NIGHT, A STORM HAD MOVED IN WITH HVY RAIN AND DROPPING TEMPS. WHILE INSTALLING THE FAN BLADES AND SPINNER, I FORGOT TO REMOVE THE TEMPORARY MARKS THAT WERE PLACED ON THE BLADES BY ANOTHER SHIFT WITH A MARKER. THERE ARE VARIOUS STEPS PRIOR TO THIS STEP UNDER THE SAME SIGNATURE BLOCK DETAILING THE INSTALLATION OF THE FRONT CONE. I WAS SO INVOLVED WITH THE INSTALLATION AND TORQUE OF THE FRONT CONE, I FORGOT TO RUB THE MARKS OFF THE BLADES AND CANNOT BLAME ANYONE BUT MYSELF. I BELIEVE THAT A COMBINATION OF FACTORS WERE INVOLVED WITH OVERLOOKING THIS STEP. 1) WX, 2) CONCENTRATING ON THE INSTALLATION OF THE FAN BLADES AND THE SPINNER, AND 3) THE FACT THAT UNDER THE STEPS I WAS PERFORMING, THE BLADES WERE NOT INVOLVED YET A SUB-STEP REFS YOU FROM THE FRONT CONE AND THEN BACKTRACKS TO THE FAN BLADES WHICH ARE NOT INVOLVED WITH THE INSTALLATION CURRENTLY AT HAND.

Data retrieved from NASA's ASRS site as of July 2007 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.