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Individual engines may be excepted from current standards as described in this section. Excepted engines must conform to regulatory conditions specified for an exception in this part and other applicable regulations. Excepted engines are deemed to be “subject to” the standards of this part even though they are not required to comply with the otherwise applicable requirements. Engines excepted with respect to certain standards must comply with other standards from which they are not excepted.
(a) Spare engines. Newly manufactured engines meeting the definition of “spare engine” are automatically excepted as follows:
(1) This exception allows production of a newly manufactured engine for installation on an in-use aircraft. It does not allow for installation of a spare engine on a new aircraft.
(2) Spare engines excepted under this paragraph (a) may be used only if they are certificated to emission standards equal to or lower than those of the engines they are replacing, for all regulated pollutants.
(3) Engine manufacturers do not need to request approval to produce spare engines, but must include information about spare engine production in the annual report specified in §1031.150(d).
(4) The permanent record for each engine excepted under this paragraph (a) must indicate that the engine was manufactured as an excepted spare engine.
(5) Engines excepted under this paragraph (a) must be labeled with the following statement: “EXCEPTED SPARE”.
(b) [Reserved]
[87 FR 72351, Nov. 23, 2022]