Code of Federal Regulations

Title 14 - Aeronautics and Space
Volume: 1Date: 2023-01-01Original Date: 2023-01-01Title: Section 25.1549 - Powerplant and auxiliary power unit instruments.Context: Title 14 - Aeronautics and Space. CHAPTER I - FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION. SUBCHAPTER C - AIRCRAFT. PART 25 - AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES. Subpart G - Operating Limitations and Information. - Markings and Placards.
§ 25.1549 Powerplant and auxiliary power unit instruments. For each required powerplant and auxiliary power unit instrument, as appropriate to the type of instrument— (a) Each maximum and, if applicable, minimum safe operating limit must be marked with a red radial or a red line; (b) Each normal operating range must be marked with a green arc or green line, not extending beyond the maximum and minimum safe limits;
Code of Federal Regulations / Title 14 - Aeronautics and Space / Vol. 1 / 2023-01-01368
(c) Each takeoff and precautionary range must be marked with a yellow arc or a yellow line; and (d) Each engine, auxiliary power unit, or propeller speed range that is restricted because of excessive vibration stresses must be marked with red arcs or red lines. [Amdt. 25–40, 42 FR 15044, Mar. 17, 1977]