Federal regulations · Through 2026-08-25 · Newer source version available

40 CFR 1031.90: Supersonic engines.

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 = 140·0.92 rPR
(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

Where this section sits in the code

Title 40—Protection of Environment
CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY
SUBCHAPTER U—AIR POLLUTION CONTROLS
PART 1031—CONTROL OF AIR POLLUTION FROM AIRCRAFT ENGINES
Subpart B—Emission Standards and Measurement Procedures

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 = 140·0.92 rPR

(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

Collected 2026-08-27T02:26:04Z. Source file · JSON

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