CFR > Title 14 - Aeronautics and Space > CHAPTER I—FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION > SUBCHAPTER C—AIRCRAFT (parts 21 to 50) > PART 25—AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES > SUBPART D—Design and Construction (§25.601 to §25.899) > 25.609—Protection of structure.

25.609—Protection of structure.

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 provisions for ventilation and drainage where necessary for protection.