A B747-200 ACFT #4 ENGINE FAN BLADE WAS FOUND WITH A BEND AT THE BLADE TIP. MEASUREMENTS WITHIN LIMITS AND CORROBORATED. LATER MEASUREMENTS FOUND BLADE BEND OUT OF LIMITS.

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I WAS THE FLT MAINT REPRESENTATIVE ON ACFT X. AFTER ARR AT THE STATION; I NOTED THAT A FAN BLADE ON #4 ENG HAD A DISTORTION (BEND) AT THE TIP (AREA 'D' OF BOEING AIRFRAME MAINT MANUAL). I MEASURED THE DISTORTION. I RECALL MEASURING AND RECORDING THE TOTAL DISTORTION DISPLACEMENT AS APPROX 0.400 INCHES WITH A LENGTH OF DISTORTION AS APPROX 2.5 INCHES (I DON'T RECALL THE EXACT DIMENSIONS AT THIS TIME). THE DISTORTION DIMENSIONS I MEASURED WERE WITHIN THE LIMITS DESCRIBED IN AMM 72-31-02 PAGE 601 1C (2)(T); WHICH ALLOWS UP TO 0.500 INCHES OF DISTORTION WITH A MAX DISTORTION LENGTH OF 6 TIMES THE DISTORTION DISPLACEMENT (SO; MAX 0.5 INCHES BY 3.0 INCHES). THE DAMAGE I RECORDED WAS WITHIN THESE LIMITS. I MADE AN ACFT MAINT LOG ENTRY DETAILING THE DAMAGE AND MY FINDINGS THAT THE DAMAGE WAS WITHIN SERVICEABLE LIMITS. SINCE THAT TIME; SEVERAL OTHER COMPANY REPRESENTATIVES HAVE EXAMINED THE DAMAGE; MADE MEASUREMENTS; AND FORWARDED PHOTOGRAPHS TO HEADQUARTERS WITH STATEMENTS CORROBORATING MY FINDINGS IN THE FIELD. HOWEVER; SINCE THEN; APPARENTLY; THE DIMENSIONS OF THE DAMAGE HAVE CHANGED -- WHETHER BY THE HAND OF ANOTHER ATTEMPTING TO WORK-OUT THE DISTORTION (UNDOCUMENTED) OR BY SUBSEQUENT ADDITIONAL DAMAGE; I CANNOT SAY. THE DAMAGE WAS AS I DESCRIBED AND DOCUMENTED AT THE TIME I DESCRIBED AND DOCUMENTED IT.