Which type of maintenance is NOT typically required for the APU on the C-130J?

The type of maintenance that is not typically required for the Auxiliary Power Unit (APU) on the C-130J is structural repairs. The APU is primarily a self-contained unit that provides pneumatic power for engine starting and electrical power when the main engines are not running. Regular inspections, filter changes, and oil checks are critical maintenance tasks that ensure the APU operates efficiently and reliably.

Structural repairs would generally imply some sort of damage or alteration to the physical framework of the aircraft or its components, which does not apply to routine APU maintenance. The APU is designed for operational reliability with parts that are routinely checked and maintained, preventing the need for structural interventions in normal operating conditions. This makes structural repairs an atypical requirement for APU maintenance compared to the other options that are routine and necessary for optimal performance.