Code of Federal Regulations

Title 14 - Aeronautics and Space
Volume: 1Date: 2020-01-01Original Date: 2020-01-01Title: Section § 27.1509 - Rotor speed.Context: Title 14 - Aeronautics and Space. CHAPTER I - FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION. SUBCHAPTER C - AIRCRAFT. PART 27 - AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT. Subpart G - Operating Limitations and Information. - Operating Limitations.
§ 27.1509 Rotor speed. (a) Maximum power-off (autorotation). The maximum power-off rotor speed must be established so that it does not exceed 95 percent of the lesser of— (1) The maximum design r.p.m. determined under § 27.309(b); and (2) The maximum r.p.m. shown during the type tests. (b) Minimum power off. The minimum power-off rotor speed must be established so that it is not less than 105 percent of the greater of— (1) The minimum shown during the type tests; and (2) The minimum determined by design substantiation. (c) Minimum power on. The minimum power-on rotor speed must be established so that it is— (1) Not less than the greater of— (i) The minimum shown during the type tests; and (ii) The minimum determined by design substantiation; and (2) Not more than a value determined under § 27.33(a)(1) and (b)(1).