Narrative:

Aircraft was the late routine overnight check and was scheduled 21.3 production hours on the aircraft. The aft arrived at XA55 was due out at XF00. Available maintenance time was approximately 4 hours (1/2 hours to let passenger off and 1/2 to be clear of the aircraft in the morning). ZZZ had 4 routine overnight checks for the night. Staffing included 4 mechanics and 1 lead mechanic. A 200 hour inter compressor case borescope inspection was scheduled for the #2 engine. #1 engine was exempt due to being post service bulletin 35152. The level 2 borescope qualified mechanic determined that there was a crack in the 'lip' at the 3 O'clock position. Aircraft records has no record that a time deferred item was generated to downgrade and track the engine at a new 65 hour interval. Spokane did not report a time deferred item generation for the #2 engine on the ZZZ activity report. No non routine talley was received in ZZZ1 indicating a time deferred item was generated. A review of the records indicates that the engineering order was reissued to ZZZ1 for the same serial number engine on apr/xa/06. The borescope mechanic at that time determined that there were 'no cracks' found. May/xa/06; I was informed that air carrier X was being stopped in ZZZ3 to perform a borescope. Callback conversation with reporter revealed the following information: the reporter stated there was no mrsi initiated by the station on the inter compressor case crack. The mrsi is a time deferred item authorized by engineering order to allow inspections to be performed at greater than 65 hour intervals. This inter compressor case crack could have slipped through the cracks and never be visible without the mrsi. Fortunately the technician accomplishing the borescope did report the findings and clear the callout that forced the inspection.

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Original NASA ASRS Text

Title: A DHC8-400 #2 ENG INTER COMPRESSOR CASE BORESCOPE INSPECTION FOUND A CRACK. INSPECTOR RPTED CRACK BUT FAILED TO INITIATE A TIME DEFERRAL FOR 65 HR INSPECTION INTERVAL PER ENGINEERING ORDER.

Narrative: ACFT WAS THE LATE ROUTINE OVERNIGHT CHK AND WAS SCHEDULED 21.3 PRODUCTION HRS ON THE ACFT. THE AFT ARRIVED AT XA55 WAS DUE OUT AT XF00. AVAILABLE MAINT TIME WAS APPROX 4 HRS (1/2 HRS TO LET PAX OFF AND 1/2 TO BE CLR OF THE ACFT IN THE MORNING). ZZZ HAD 4 ROUTINE OVERNIGHT CHKS FOR THE NIGHT. STAFFING INCLUDED 4 MECHS AND 1 LEAD MECH. A 200 HR INTER COMPRESSOR CASE BORESCOPE INSPECTION WAS SCHEDULED FOR THE #2 ENG. #1 ENG WAS EXEMPT DUE TO BEING POST SVC BULLETIN 35152. THE LEVEL 2 BORESCOPE QUALIFIED MECH DETERMINED THAT THERE WAS A CRACK IN THE 'LIP' AT THE 3 O'CLOCK POS. ACFT RECORDS HAS NO RECORD THAT A TIME DEFERRED ITEM WAS GENERATED TO DOWNGRADE AND TRACK THE ENG AT A NEW 65 HR INTERVAL. SPOKANE DID NOT RPT A TIME DEFERRED ITEM GENERATION FOR THE #2 ENG ON THE ZZZ ACTIVITY RPT. NO NON ROUTINE TALLEY WAS RECEIVED IN ZZZ1 INDICATING A TIME DEFERRED ITEM WAS GENERATED. A REVIEW OF THE RECORDS INDICATES THAT THE ENGINEERING ORDER WAS REISSUED TO ZZZ1 FOR THE SAME SERIAL NUMBER ENG ON APR/XA/06. THE BORESCOPE MECH AT THAT TIME DETERMINED THAT THERE WERE 'NO CRACKS' FOUND. MAY/XA/06; I WAS INFORMED THAT ACR X WAS BEING STOPPED IN ZZZ3 TO PERFORM A BORESCOPE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THERE WAS NO MRSI INITIATED BY THE STATION ON THE INTER COMPRESSOR CASE CRACK. THE MRSI IS A TIME DEFERRED ITEM AUTHORIZED BY ENGINEERING ORDER TO ALLOW INSPECTIONS TO BE PERFORMED AT GREATER THAN 65 HR INTERVALS. THIS INTER COMPRESSOR CASE CRACK COULD HAVE SLIPPED THROUGH THE CRACKS AND NEVER BE VISIBLE WITHOUT THE MRSI. FORTUNATELY THE TECHNICIAN ACCOMPLISHING THE BORESCOPE DID RPT THE FINDINGS AND CLR THE CALLOUT THAT FORCED THE INSPECTION.

Data retrieved from NASA's ASRS site as of January 2009 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.