Narrative:

The situation here affects approximately 5 B737-200 aircraft. The first was brought in for an (corrosion check) 'right' check on nov/xx/95 and the last was in on jan/xx/96. The problem occurred while complying with airworthiness directive 95- 12-17. This calls for replacement of cracked chord angles at sta 727 on the B737 aircraft. The repair for this is specified in maintenance manual and boeing drawing. Our crew was new to the job and asked for guidance and advice from another crew that had previously accomplished the repair. Through a miscom we were informed that two fasteners that were trapped beneath structure be ground flush and not picked up. One fastener was on the new chord and one was on an existing stiffener removed for access. The print we were given of boeing drawing for the first aircraft had a hand written note to this effect we were told was from engineering. This information was passed on, and subsequently approximately four other aircraft were repaired the same way. On aug/thu/96, while working the same job we were made aware that this procedure was not approved. This aircraft was repaired properly, and the engineering department was notified of the situation. They are currently in contact with boeing to rectify the problem on the previous aircraft repaired incorrectly. Callback conversation with reporter revealed the following information: reporter stated that the grinding off of the bulk head fasteners was not legally authority/authorized by the manufacturer of the aircraft, boeing. However, since the other end of the fasteners are covered by a casting, there is no danger that they will fall out and cause interference with other parts. Therefore, the reporter's company fleet engineer is working with boeing to obtain authority/authorized for the grinding of the fasteners covering all past and future repairs in the same manner. This procedure is actually safer than removing all the structure necessary to uncover the other end of the fasteners.

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Original NASA ASRS Text

Title: MECH OF A B737-200 RPTS AN UNAUTH REPAIR TO 5 SAME MAKE AND MODEL ACFT.

Narrative: THE SIT HERE AFFECTS APPROX 5 B737-200 ACFT. THE FIRST WAS BROUGHT IN FOR AN (CORROSION CHK) 'R' CHK ON NOV/XX/95 AND THE LAST WAS IN ON JAN/XX/96. THE PROB OCCURRED WHILE COMPLYING WITH AIRWORTHINESS DIRECTIVE 95- 12-17. THIS CALLS FOR REPLACEMENT OF CRACKED CHORD ANGLES AT STA 727 ON THE B737 ACFT. THE REPAIR FOR THIS IS SPECIFIED IN MAINT MANUAL AND BOEING DRAWING. OUR CREW WAS NEW TO THE JOB AND ASKED FOR GUIDANCE AND ADVICE FROM ANOTHER CREW THAT HAD PREVIOUSLY ACCOMPLISHED THE REPAIR. THROUGH A MISCOM WE WERE INFORMED THAT TWO FASTENERS THAT WERE TRAPPED BENEATH STRUCTURE BE GROUND FLUSH AND NOT PICKED UP. ONE FASTENER WAS ON THE NEW CHORD AND ONE WAS ON AN EXISTING STIFFENER REMOVED FOR ACCESS. THE PRINT WE WERE GIVEN OF BOEING DRAWING FOR THE FIRST ACFT HAD A HAND WRITTEN NOTE TO THIS EFFECT WE WERE TOLD WAS FROM ENGINEERING. THIS INFO WAS PASSED ON, AND SUBSEQUENTLY APPROX FOUR OTHER ACFT WERE REPAIRED THE SAME WAY. ON AUG/THU/96, WHILE WORKING THE SAME JOB WE WERE MADE AWARE THAT THIS PROC WAS NOT APPROVED. THIS ACFT WAS REPAIRED PROPERLY, AND THE ENGINEERING DEPT WAS NOTIFIED OF THE SIT. THEY ARE CURRENTLY IN CONTACT WITH BOEING TO RECTIFY THE PROB ON THE PREVIOUS ACFT REPAIRED INCORRECTLY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THAT THE GRINDING OFF OF THE BULK HEAD FASTENERS WAS NOT LEGALLY AUTH BY THE MANUFACTURER OF THE ACFT, BOEING. HOWEVER, SINCE THE OTHER END OF THE FASTENERS ARE COVERED BY A CASTING, THERE IS NO DANGER THAT THEY WILL FALL OUT AND CAUSE INTERFERENCE WITH OTHER PARTS. THEREFORE, THE RPTR'S COMPANY FLEET ENGINEER IS WORKING WITH BOEING TO OBTAIN AUTH FOR THE GRINDING OF THE FASTENERS COVERING ALL PAST AND FUTURE REPAIRS IN THE SAME MANNER. THIS PROC IS ACTUALLY SAFER THAN REMOVING ALL THE STRUCTURE NECESSARY TO UNCOVER THE OTHER END OF THE FASTENERS.

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.