AN INSPECTION SUPERVISOR; LEAD MECHANIC AND MAINT CONTROLLER DESCRIBE THE EVENTS THAT CONTRIBUTED TO A B-737 BEING RELEASED WITH A R INBOARD TRAILING EDGE FLAP PUNCTURE DAMAGE EXCEEDING SRM LIMITS.

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DURING OVERNIGHT CHK; FOUND R INBOARD TRAILING EDGE AFT FLAP DAMAGED; WITH A PUNCTURE. ZZZ MAINT REQUESTED A DEFERRAL PER SRM; ALLOWABLE DMG 2; AND MAINT CTL ISSUED DEFERRAL CTL # ZZZ TO INSPECT EVERY 150 FLT HRS AND PERMANENT REPAIR WITHIN 5000 FLT HRS. THE ZZZ TECHNICIAN DID NOT ENTER ANY DIMENSIONS FOR THE DAMAGE AND WHEN DEFERRAL WAS PROCESSED NO DIMENSIONS WERE ENTERED. ENGINEERING REVIEWED LOG PAGE AND FOUND NO REF TO DIMENSIONS. THE ACFT WAS STOPPED AT ZZZ ON MAR/XX/08 ON A THROUGH-FLT AND INSPECTED. THE PUNCTURE WAS MEASURED AT APPROX .312 INCHES; .250 INCHES MAX ALLOWABLE PER SRM. SHEET METAL CLEANED UP THE DAMAGE; FILLED WITH FAST WELD AND A NEW DEFERRAL ISSUED TO INSPECT DAILY AND REPAIR WITHIN 3 DAYS PER AN ENGINEERING DOCUMENT. ACFT TOOK A 90 MIN DELAY. I WILL REVIEW ALL DEFERRAL REQUESTS AND ENSURE DIMENSIONS ARE RECORDED IN THE MAINT COMPUTER SYS ENTRY AND IF NOT; CONTACT MAINT CTL TO ENSURE ALL DIMENSIONS ARE ENTERED AND THAT THEY ARE WITHIN LIMITS PER THE BASIS FOR DEFERRAL. DID NOT FOLLOW UP WITH MAINT CTL TO ENSURE DIMENSIONS WERE ENTERED AS REQUIRED. QUALITY CTL SUPVR ON DUTY HAD A VERY HVY WORKLOAD AND ASKED IF I COULD HELP GET THE DEFERRALS CAUGHT UP. THERE WERE A LOT OF DEFERRALS THAT HAD NOT BEEN WORKED FROM OTHER SHIFTS AND I STARTED PROCESSING THEM. IN MY HASTE I FAILED TO NOTE THAT THERE WERE NO DIMENSIONS ENTERED INTO MAINT COMPUTER SYS FOR THE LOG PAGE FOR THE DEFERRAL AND PROCESSED THE DEFERRAL. ENGINEERING CAUGHT THE ERROR AND ACFT RE-INSPECTED ON A THROUGH-FLT; FOUND DAMAGE TO BE OUT OF SRM LIMITS. ENGINEERING DOCUMENT ISSUED FOR INTERIM REPAIR. SUPPLEMENTAL INFO FROM ACN 779928: RECEIVED CALL REQUESTING DEFERRAL FOR HOLE IN R AFT INBOARD TRAILING EDGE FLAP LOWER SKIN. WAS INFORMED HOLE/PUNCTURE WAS IN LIMITS PER SRM BUT TECHNICIANS QUESTIONED AREA ON FLAP AS TO CRITICAL/NON CRITICAL AREA. VERIFIED WITH TECHNICIANS AND SRM THAT DAMAGE AREA WAS IN NON CRITICAL AREA. I NEVER QUESTIONED THE TECHNICIAN'S ASSESSMENT OF HOLE DAMAGE DIAMETER DUE TO HIS ASSURANCE THAT IT WAS WITHIN LIMITS. DEFERRAL WAS CLOSED; DAMAGE WAS RE-EVALUATED AND NEW DEFERRAL DEFERRED MAINT ISSUED. SUPPLEMENTAL INFO FROM ACN 779929: FOUND PUNCTURE ON R INBOARD TRAILING EDGE AFT FLAP SKIN. OK'ED MEASUREMENTS OF HOLE TO BE 5/16 X 3/16. CHKED B737-900 SRM. DAMAGE WAS IN NON CRITICAL AREA AND JUST OUT OF LIMITS. CALLED MAINT CTL AND PLACED ITEM ON DEFERRAL. MISCALCULATED MEASUREMENTS OF DAMAGE. FELT DAMAGE WAS NOT UNSAFE OR UNAIRWORTHY. HAD OTHER LEAD DUTIES TO PERFORM AND DAMAGE WAS DOCUMENTED.