14 CFR 91.815 Agricultural and fire fighting airplanes: Noise operating limitations
Subpart I—Operating Noise Limits
A reference copy of the official regulation text for study. It is not legal advice or an FAA interpretation; always confirm against the current official source.
(a) This section applies to propeller-driven, small airplanes having standard airworthiness certificates that are designed for “agricultural aircraft operations” (as defined in § 137.3 of this chapter, as effective on January 1, 1966) or for dispensing fire fighting materials.
(b) If the Airplane Flight Manual, or other approved manual material information, markings, or placards for the airplane indicate that the airplane has not been shown to comply with the noise limits under part 36 of this chapter, no person may operate that airplane, except—
(1) To the extent necessary to accomplish the work activity directly associated with the purpose for which it is designed;
(2) To provide flight crewmember training in the special purpose operation for which the airplane is designed; and
(3) To conduct “nondispensing aerial work operations” in accordance with the requirements under § 137.29(c) of this chapter.