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87 FR 72351, Nov. 23, 2022, unless otherwise noted.
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The following standards apply to turboprop engines with rated output at or above 1,000 kW:
(a) Smoke. Engines of a type or model for which the date of manufacture of the individual engine is on or after January 1, 1984, may not have a characteristic level for smoke number exceeding the following value:
SN = 187·rO−0.168
(b) [Reserved]