Narrative:

Aircraft taxied to parking position and when captain applied parking brake, #3 brake lower flex line failed. I was working the line on another aircraft, so lead mechanic called another mechanic on duty to bring applicable line from maintenance office where manuals and parts are stored. The failed line had an illegible identification tag, but it was noted during installation that the replacement line was approximately 3-4 inches shorter than original. This was discussed with the lead mechanic, but all agreed it had to be the proper part number from past experience and manual reference from other mechanic on duty. Part number X was installed and logbook discrepancy signed off, and aircraft returned to service. Upon return to the office where manuals are kept, further research indicated 2 possible part numbers, based on aircraft serial number. Maintenance control was called, and aircraft instructed to return to gate prior to further flight until verification of proper part number. (Aircraft never flew with improper part number line.) it was finally verified that part number X should be installed. Part was shipped in from another station, improper line was removed and replaced prior to flight, and aircraft returned to service.

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Original NASA ASRS Text

Title: A DEHAVILLAND -8 WAS RELEASED FOR SVC BUT WAS RETURNED TO THE GATE DUE TO FINDING AN INCORRECT HIGH PRESSURE HOSE INSTALLED ON #3 BRAKE.

Narrative: ACFT TAXIED TO PARKING POS AND WHEN CAPT APPLIED PARKING BRAKE, #3 BRAKE LOWER FLEX LINE FAILED. I WAS WORKING THE LINE ON ANOTHER ACFT, SO LEAD MECH CALLED ANOTHER MECH ON DUTY TO BRING APPLICABLE LINE FROM MAINT OFFICE WHERE MANUALS AND PARTS ARE STORED. THE FAILED LINE HAD AN ILLEGIBLE ID TAG, BUT IT WAS NOTED DURING INSTALLATION THAT THE REPLACEMENT LINE WAS APPROX 3-4 INCHES SHORTER THAN ORIGINAL. THIS WAS DISCUSSED WITH THE LEAD MECH, BUT ALL AGREED IT HAD TO BE THE PROPER PART NUMBER FROM PAST EXPERIENCE AND MANUAL REF FROM OTHER MECH ON DUTY. PART NUMBER X WAS INSTALLED AND LOGBOOK DISCREPANCY SIGNED OFF, AND ACFT RETURNED TO SVC. UPON RETURN TO THE OFFICE WHERE MANUALS ARE KEPT, FURTHER RESEARCH INDICATED 2 POSSIBLE PART NUMBERS, BASED ON ACFT SERIAL NUMBER. MAINT CTL WAS CALLED, AND ACFT INSTRUCTED TO RETURN TO GATE PRIOR TO FURTHER FLT UNTIL VERIFICATION OF PROPER PART NUMBER. (ACFT NEVER FLEW WITH IMPROPER PART NUMBER LINE.) IT WAS FINALLY VERIFIED THAT PART NUMBER X SHOULD BE INSTALLED. PART WAS SHIPPED IN FROM ANOTHER STATION, IMPROPER LINE WAS REMOVED AND REPLACED PRIOR TO FLT, AND ACFT RETURNED TO SVC.

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.