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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.
Each person manufacturing propellers under a type certificate must give each variable pitch propeller an acceptable functional test to determine if it operates properly throughout the normal range of operation.