Aircraft Maintenance Practices and Inspection
Maintenance Practices and Inspection tests how tasks are planned, performed, inspected and released. The exam favours work-card discipline, torque control, inspection independence and return-to-service documentation.
Maintenance logic
MSG-3 develops scheduled tasks from failure consequences; A and C checks are interval-based, not type approvals. A maintenance release certifies that listed work was completed. The MEL permits dispatch with specified defects under conditions; it is not a repair or an extension of an AD.
Inspection and assembly
Use calibrated tools; torque values apply to the fastener unless a special procedure says otherwise. Lockwire must pull in the tightening direction; cotter pins must fit without being reused if deformed. Duplicate or independent inspection is required for critical assemblies such as flight controls and engine controls.
Worked example
A torque wrench of length L = 0.40 m is used with an in-line extension E = 0.10 m. The wrench reads at its handle, so the setting for a desired 50 N·m is T_set = 50 × 0.40/(0.40 + 0.10) = 40 N·m. The extension increases effective lever length; setting 50 N·m would over-torque the fastener by 25%. For a crowfoot at 90°, the length correction is different.
Traps
Signing a task before the inspection is complete, using a superseded work card, or accepting a use-by torque after rework. FOD and tool control are inspection items, not housekeeping.