Commercial Fixed Wing
Troubleshooting; Workload; Time Pressure
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Other / Unknown; Ground Event / Encounter Person / Animal / Bird
General Maintenance Action
Manuals; Procedure; Human Factors; Company Policy
In ZZZ a mouse sighting was reported. A [Maintenance Control] logpage was opened to schedule a rodent capture treatment with open as required per Aircraft Appearance Manual 10-XX-XX. Before treatment occurred; on Flight XXXX; inbound to ZZZ1 crew [requested priority handling] due to the 'LE flaps transit' amber annunciator lighting up along with all the amber annunciators illuminating on the overhead 'LE devices annunciator panel'. After troubleshooting Technical Support found a dried puddle of pee and feces on top and below the FSEU (Flap Slat Electronic Unit) on the rack. For reference to fault history; similar write-up was also reported inbound to ZZZ2 and FSEU was replaced at that time in ZZZ2.We still have not caught the rodent; and this isn't a one-time problem with rodents damaging aircraft. A brief review of history I've found the small list below but there are more aircraft with similar rodent sighting reports.1) Aircraft Y; rodent spotted in overhead life raft compartment. Scheduled treatment with no rodent found.2) Aircraft Z had multiple sightings; 11 logpages of sightings in multiple locations.3) Aircraft A in C-check. Aircraft remained there until all blankets and wire repairs completed.4) Aircraft B multiple sightings; mouse was eventually caught.5) Aircraft C multiple reports again with wiring damage found caused by mice. Engineering had to write [a request] to perform a Nitrogen Fumigation to ensure mouse was eradicated.Possibly review our current policy of scheduling treatment. Due to possibility of wiring damage causing any number of critical problems with the aircraft and extensive down OOS (Out Of Service) time required for repairs when damage is finally found; I'm not sure waiting to schedule a treatment within a few days is the best procedure. Possibly a 1 flight [with Deferred Item] to get aircraft back to hub for treatment ASAP instead of when schedule permits downline. Not sure best way to handle situation but there could be a better way to ensure the safety of our passengers and crew.
Aircraft Maintenance Technician reported a flight control anomaly attributed to damage caused by rodents. Multiple rodent sightings reported on multiple aircraft.