Which reference is essential for determining if a control surface must be checked after painting?

The manufacturer's service manual is essential for determining if a control surface must be checked after painting because it provides specific instructions and guidelines related to that aircraft's design, construction, and maintenance requirements. These manuals include detailed procedures for inspections and any precautions that need to be considered after painting, such as operational checks or adjustments required to ensure the control surface functions correctly and safely.

Manufacturers often include critical information regarding the materials used in painting and the potential effects on flight control functionality. Compliance with these instructions is vital for maintaining airworthiness and safety standards.

While the aircraft's operational handbook, FAA regulations, and the maintenance logbook serve important roles in the overall operation and record-keeping for the aircraft, they may not contain the specific technical guidance needed for post-painting inspections of control surfaces that is typically outlined in the manufacturer's service manual.