Narrative:

Cracked thrust reverser blocker door on left engine found by aircraft maintenance. During removal of blocker door per cdl; one or more parts of the attachment hardware were dropped in the engine aft of the fan section. Thrust reverser was deployed during the maintenance procedure; creating numerous openings into which the parts could have fallen. Maintenance personnel searched for the missing parts in and around the engine but could not find them. Flight crew became aware of the missing parts during exterior preflight inspection upon observing numerous maintenance personnel searching in engine with flashlights and noting that the two attachment hardware assemblies on the removed blocker door did not look the same. See attached document for pictures of the two attachment hardware assemblies. Maintenance presented logbook to flight crew with ETOPS preflight check noted complete and 1 blocker door removed and deferred per cdl. No entry made by maintenance about missing parts from blocker door attachment assembly. Flight crew made a logbook write-up regarding missing 'hardware'; maintenance signed off write-up as hardware removed from aircraft per procedure. During crew review of logbook; ca claimed to have pertinent maintenance knowledge because he possesses an airframe and powerplant mechanic license; and he stated that even if the missing parts were still somewhere in the engine he was confident that they could not cause a problem. After discussion the crew elected to accept aircraft and depart. Damaged blocker door discovered by aircraft maintenance. Time pressure due to passengers onboard. Difficult maintenance procedure to accomplish due to tight space. For international departures requiring an ETOPS inspection; have passenger service check with aircraft maintenance prior to boarding. Have a secure place for maintenance personnel to store loose parts during a procedure.

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Original NASA ASRS Text

Title: B787 Flight Crew reported that maintenance was unable to locate some hardware that was dropped aft of the engine fan area.

Narrative: Cracked thrust reverser blocker door on left engine found by aircraft maintenance. During removal of blocker door per CDL; one or more parts of the attachment hardware were dropped in the engine aft of the fan section. Thrust reverser was deployed during the Maintenance procedure; creating numerous openings into which the parts could have fallen. Maintenance personnel searched for the missing parts in and around the engine but could not find them. Flight crew became aware of the missing parts during exterior preflight inspection upon observing numerous Maintenance personnel searching in engine with flashlights and noting that the two attachment hardware assemblies on the removed blocker door did not look the same. See attached document for pictures of the two attachment hardware assemblies. Maintenance presented logbook to flight crew with ETOPS preflight check noted complete and 1 blocker door removed and deferred per CDL. No entry made by Maintenance about missing parts from blocker door attachment assembly. Flight crew made a logbook write-up regarding missing 'hardware'; Maintenance signed off write-up as hardware removed from aircraft per procedure. During crew review of logbook; CA claimed to have pertinent Maintenance knowledge because he possesses an Airframe and Powerplant mechanic license; and he stated that even if the missing parts were still somewhere in the engine he was confident that they could not cause a problem. After discussion the crew elected to accept aircraft and depart. Damaged blocker door discovered by aircraft Maintenance. Time pressure due to passengers onboard. Difficult Maintenance procedure to accomplish due to tight space. For international departures requiring an ETOPS inspection; have passenger service check with aircraft Maintenance prior to boarding. Have a secure place for Maintenance personnel to store loose parts during a procedure.

Data retrieved from NASA's ASRS site 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.