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87 FR 72351, Nov. 23, 2022, unless otherwise noted.
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The following standards apply to new engines installed in supersonic airplanes:
(a) Smoke. Engines of a type or model for which the date of manufacture was on or after January 1, 1984, may not have a characteristic level for smoke number exceeding an emission standard that is the lesser of 50 or the following:
SN = 83.6·rO−0.274
(b) [Reserved]
(c) HC. Engines of a type or model for which the date of manufacture was on or after January 1, 1984, may not have a characteristic level for HC exceeding the following emission standard in g/kN rated output:
HC = 140·0.92rPR
(d) CO. Engines of a type or model for which the date of manufacture was on or after July 18, 2012, may not have a characteristic level for CO exceeding the following emission standard in g/kN rated output:
CO = 4550·rPR−1.03
(e) NOX Engines of a type or model for which the date of manufacture was on or after July 18, 2012, may not have a characteristic level for NOX engines exceeding the following emission standard in g/kN rated output:
NOX = 36+2.42·rPR