Maintenance Practices and Airworthiness Procedures
Documentation and release
Airworthiness is proven by paperwork as much as by hardware. Know the maintenance release (certifies the task is complete and the aircraft is fit for the next flight), the certificate of release to service, the approved maintenance programme, the minimum equipment list (MEL) with its categories and dispatch conditions, the configuration deviation list (CDL), and the airworthiness directive (mandatory, with compliance time). Understand the difference between an AD, a service bulletin (usually manufacturer-recommended, not automatically mandatory) and an alert service bulletin.
Practices
Know torque procedures (calibrated wrench, torque wrench extension correction, friction drag), lockwiring and tab-washer practices, safetying, control rigging checks, leak testing, and the rules for standard parts versus approved parts and for fabrication versus repair. Know the meaning of bonding and grounding in maintenance, the use of the technical log and deferred defect process, and the rule that all maintenance must be recorded and traceable.
Traps
Questions test who may defer a defect (only per the MEL, with the correct category and any operational or maintenance procedure), the fact that an AD overrides a service bulletin, and that a maintenance release is not a C of A. They test torque wrench extension maths and the rule that a self-locking nut is not reused beyond limits.
Worked example
A torque wrench with an extension is set to 100 Nm at a 90° extension. Because the extension is perpendicular, the applied torque equals the indicated torque - no correction. Only in-line extensions change the effective length and require correction.
Rule of thumb
Ask: Is it mandatory, is it approved, is it recorded, and who may sign?