Experience in following detailed instructions in making routine, reoccurring repairs and modifications to aircraft parts, subassemblies, and components, e.g., such as jacking and leveling aircraft, installing, and adjusting engines, landing gear assemblies, instrument panels, and flight control systems.???????. Work involves the maintenance, troubleshooting, repair, overhaul, and modification of fixed and rotary wing aircraft systems, airframes, components and assemblies, where the work requires substantive knowledge of the airframe and aircraft mechanical, pneudraulic, and/or electrical systems and their interrelationships.