§ 1031.60 Subsonic turbojet and turbofan engines above 26.7 kN thrust.
The following standards apply to new turbofan or turbojet aircraft engines with rated output above 26.7 kN thrust that are installed in subsonic aircraft:
(a) Smoke. (1) Tier 0. Except as specified in (a)(2) of this section, engines of a type or model with rated output at or above 129 kN, and for which the date of manufacture of the individual engine after January 1, 1976 and is before January 1, 1984 may not have a characteristic level for smoke number exceeding the following emission standard:
(2) JT8D and JT3D engines. (i) Engines of the type JT8D for which the date of manufacture of the individual engine is on or after February 1, 1974, and before January 1, 1984 may not have a characteristic level for smoke number exceeding an emission standard of 30.
(ii) Engines of the type JT3D for which the date of manufacture of the individual engine is on or after January 1, 1978 and before January 1, 1984 may not have a characteristic level for smoke number exceeding an emission standard of 25.
(3) Tier 0 in-use. Except for engines of the type JT8D and JT3D, in-use engines with rated output at or above 129 kN thrust may not exceed the following smoke number standard:
(4) JT8D in-use. In-use aircraft engines of the type JT8D may not exceed a smoke number standard of 30.