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42 U.S.C. 7572; 49 U.S.C. 106(f), 40105, 40113, 44701-44702, 44704, 44707, 44709, 44711, 44713, 44715, 45303.
Docket No. 5085, 29 FR 14568, Oct. 24, 1964, unless otherwise noted.
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1. For miscellaneous amendments to cross references in this 21 see Amdt. 21-10, 31 FR 9211, July 6, 1966.
2. Nomenclature changes to part 21 appear at 74 FR 53384, Oct. 16, 2009.
(a) Each applicant for a supplemental type certificate must show that the altered product meets applicable requirements specified in § 21.101 and—
(1) In the case of an acoustical change described in § 21.93(b), show compliance with the applicable noise requirements of part 36 of this chapter;
(2) In the case of an emissions change described in § 21.93(c), show compliance with the applicable fuel venting and exhaust emissions requirements of part 34 of this chapter; and
(3) In the case of a fuel efficiency change described in § 21.93(d), show compliance with the applicable fuel efficiency requirements of part 38 of this chapter.
(b) Each applicant for a supplemental type certificate must meet §§ 21.33 and 21.53 with respect to each change in the type design.
[Amdt. 21-17, 32 FR 14927, Oct. 28, 1967, as amended by Amdt. 21-42, 40 FR 1033, Jan. 6, 1975; Amdt. 21-52A, 45 FR 79009, Nov. 28, 1980; Amdt. 21-61, 53 FR 3540, Feb. 5, 1988; Amdt. 21-68, 55 FR 32860, Aug. 10, 1990; Amdt. 21-71, 57 FR 42854, Sept. 16, 1992; Amdt. 21-77, 65 FR 36266, June 7, 2000; Amdt. No. 21-107, 89 FR 12653, Feb. 16, 2024]