Sec. 23.939 - Powerplant operating characteristics.
(a) Turbine engine powerplant operating
characteristics must be investigated in flight to determine that no
adverse characteristics (such as stall, surge, or flameout) are present,
to a hazardous degree, during normal and emergency operation within the
range of operating limitations of the airplane and of the engine.
(b) Turbocharged reciprocating engine
operating characteristics must be investigated in flight to assure that no
adverse characteristics, as a result of an inadvertent overboost, surge,
flooding, or vapor lock, are present during normal or emergency operation
of the engine(s) throughout the range of operating limitations of both
airplane and engine.
(c) For turbine engines, the air inlet
system must not, as a result of airflow distortion during normal
operation, cause vibration harmful to the engine.
[Amdt. 23-7, 34 FR 13093 Aug. 13, 1969,
as amended by Amdt. 23-14, 38 FR 31823, Nov. 19, 1973; Amdt. 23-18, 42 FR
15041, Mar. 17, 1977; Amdt. 23-42, 56 FR 354, Jan. 3, 1991]