Narrative:

On the evening of sep/fri/02 aircraft arrived in with a pilot report that the #1 engine had 2 popping sounds while in reverse. The pilot thought it sounded like a possible compressor stall. I called maintenance control to make him aware of the situation and work together with him in troubleshooting this discrepancy per the maintenance manual. Also contacted in engineering and got him involved due to the recent history of similar write-ups on this aircraft. We discussed possible causes of this discrepancy and the possibility of a borescope inspection requirement. Engineering advised us that a borescope was accomplished as a result of a previous write-up describing a popping sound and told us not to perform another one as it was not required. After and I reviewed the previous 3 write-ups we felt we had no reason to question engineering's decision not to borescope the engine. A borescope team was not dispatched. The compressor discharge process venturi appeared to be clogged upon inspection. The venturi was cleaned and engine run was good per the maintenance manual. Aircraft was then returned to service.

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Original NASA ASRS Text

Title: B737-300 TECHNICIAN RPTS NOT ACCOMPLISHING A REQUIRED #1 ENG BORESCOPE FOR A COMPRESSOR STALL. ENGINEERING DECISION NOT TO BORESCOPE.

Narrative: ON THE EVENING OF SEP/FRI/02 ACFT ARRIVED IN WITH A PLT RPT THAT THE #1 ENG HAD 2 POPPING SOUNDS WHILE IN REVERSE. THE PLT THOUGHT IT SOUNDED LIKE A POSSIBLE COMPRESSOR STALL. I CALLED MAINT CTL TO MAKE HIM AWARE OF THE SIT AND WORK TOGETHER WITH HIM IN TROUBLESHOOTING THIS DISCREPANCY PER THE MAINT MANUAL. ALSO CONTACTED IN ENGINEERING AND GOT HIM INVOLVED DUE TO THE RECENT HISTORY OF SIMILAR WRITE-UPS ON THIS ACFT. WE DISCUSSED POSSIBLE CAUSES OF THIS DISCREPANCY AND THE POSSIBILITY OF A BORESCOPE INSPECTION REQUIREMENT. ENGINEERING ADVISED US THAT A BORESCOPE WAS ACCOMPLISHED AS A RESULT OF A PREVIOUS WRITE-UP DESCRIBING A POPPING SOUND AND TOLD US NOT TO PERFORM ANOTHER ONE AS IT WAS NOT REQUIRED. AFTER AND I REVIEWED THE PREVIOUS 3 WRITE-UPS WE FELT WE HAD NO REASON TO QUESTION ENGINEERING'S DECISION NOT TO BORESCOPE THE ENG. A BORESCOPE TEAM WAS NOT DISPATCHED. THE COMPRESSOR DISCHARGE PROCESS VENTURI APPEARED TO BE CLOGGED UPON INSPECTION. THE VENTURI WAS CLEANED AND ENG RUN WAS GOOD PER THE MAINT MANUAL. ACFT WAS THEN RETURNED TO SERVICE.

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.