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Aircraft and aircraft engines. Aircraft covered under §21.182 of this chapter must be identified, and each person who manufacturers an aircraft engine under a type or production certificate shall identify that engine, by means of a fireproof plate that has the information specified in §45.13 of this part marked on it by etching, stamping, engraving, or other approved method of fireproof marking. The identification plate for aircraft must be secured in such a manner that it will not likely be defaced or removed during normal service, or lost or destroyed in an accident. Except as provided in paragraphs (c), (d), and (e) of this section, the aircraft identification plate must be secured to the aircraft fuselage exterior so that it is legible to a person on the ground, and must be either adjacent to and aft of the rear-most entrance door or on the fuselage surface near the tail surfaces. For aircraft engines, the identification plate must be affixed to the engine at an accessible location in such a manner that it will not likely be defaced or removed during normal service, or lost or destroyed in an accident.