Repairs, replaces, and rebuilds aircraft structures of moderate difficulty, such as wings, fuselage, surface controls and functional components to include rigging, plumbing and hydraulic units utilizing hand tools, power tools, machines, and equipment such as shears, sheet metal brake, welding equipment, rivet guns and drills. Applies technical knowledge of aircraft system principles in determining equipment malfunctions and applies skill in restoring equipment operation, evaluates performance and reliability of prototype or production mods, and recommends changes to installation specifications to simplify assembly and maintenance.