Narrative:

While performing exterior preflight of act xyz, I found the right engine fan blade rub strip, also known as the abradable liner, damaged. Large chunks were missing from several locations, the largest, a 3 inch by 15 inch area (45 square inches). I called ZZZ maintenance, and was advised by them that the liner was within permissible limits. I asked to see those limits, and was shown a copy of maintenance manual XXX, which indicated that the maximum total area of damage could not exceed 80 square inches and that the total allowable damage in one area could not exceed 35 inches. I believed that the area damaged in just one section was 45 square inches, and asked to talk to abc technician. Abc advised me to reference maintenance manual YYY, stating that the area was out of limits. Since ZZZ and abc could not agree, and since I was able to remove sections of the rub strip easily with my bare hands, and that the strip was loose beneath the engine fan blade, and since the material was in contact with the fan blade, and the fan blade was and could continue to gouge sections of liner out into the engine, I advised dispatch that I believed the airplane to be unsafe. No interim repairs had been made to the liner since it had been written up 6 days earlier, as is required.

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Original NASA ASRS Text

Title: A B767-200 WAS DISPATCHED AND OPERATED FOR 6 DAYS IN NON COMPLIANCE WITH THE R ENG INLET FAN COWL ABRAIDABLE SHROUD WORN BEYOND LIMITS.

Narrative: WHILE PERFORMING EXTERIOR PREFLT OF ACT XYZ, I FOUND THE R ENG FAN BLADE RUB STRIP, ALSO KNOWN AS THE ABRADABLE LINER, DAMAGED. LARGE CHUNKS WERE MISSING FROM SEVERAL LOCATIONS, THE LARGEST, A 3 INCH BY 15 INCH AREA (45 SQUARE INCHES). I CALLED ZZZ MAINT, AND WAS ADVISED BY THEM THAT THE LINER WAS WITHIN PERMISSIBLE LIMITS. I ASKED TO SEE THOSE LIMITS, AND WAS SHOWN A COPY OF MAINT MANUAL XXX, WHICH INDICATED THAT THE MAX TOTAL AREA OF DAMAGE COULD NOT EXCEED 80 SQUARE INCHES AND THAT THE TOTAL ALLOWABLE DAMAGE IN ONE AREA COULD NOT EXCEED 35 INCHES. I BELIEVED THAT THE AREA DAMAGED IN JUST ONE SECTION WAS 45 SQUARE INCHES, AND ASKED TO TALK TO ABC TECHNICIAN. ABC ADVISED ME TO REF MAINT MANUAL YYY, STATING THAT THE AREA WAS OUT OF LIMITS. SINCE ZZZ AND ABC COULD NOT AGREE, AND SINCE I WAS ABLE TO REMOVE SECTIONS OF THE RUB STRIP EASILY WITH MY BARE HANDS, AND THAT THE STRIP WAS LOOSE BENEATH THE ENG FAN BLADE, AND SINCE THE MATERIAL WAS IN CONTACT WITH THE FAN BLADE, AND THE FAN BLADE WAS AND COULD CONTINUE TO GOUGE SECTIONS OF LINER OUT INTO THE ENG, I ADVISED DISPATCH THAT I BELIEVED THE AIRPLANE TO BE UNSAFE. NO INTERIM REPAIRS HAD BEEN MADE TO THE LINER SINCE IT HAD BEEN WRITTEN UP 6 DAYS EARLIER, AS IS REQUIRED.

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.