14 C.F.R. § 23.609 Protection of structure.
Title 14 - Aeronautics and Space
Each part of the structure must— (a) Be suitably protected against deterioration or loss of strength in service due to any cause, including— (1) Weathering; (2) Corrosion; and (3) Abrasion; and (b) Have adequate provisions for ventilation and drainage.
Title 14: Aeronautics and Space
PART 23—AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES
Subpart D—Design and Construction
§ 23.609 Protection of structure.
