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Table 4-34. Federal Exhaust Emissions Standards for Newly Manufactured and In-Use Aircraft Engines

Table 4-34. Federal Exhaust Emissions Standards for Newly Manufactured and In-Use Aircraft Engines

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Engine type c Pollutant Year of engine manufacture
1974-75 1976-77 1978-82 1983 1984-96 1997-99 2000+
TurbopropSmoke         h187(rO)-0.168 h187(rO)-0.168 h187(rO)-0.168
Class T3 turbojet CO (g/kN) d           118 118
HC (g/kN) d         19.6 19.6 19.6
NOx (g/kN) d  &         j40 + 2(rPR) k32 + 1.6(rPR)
Smoke     25 25 i83.6(rO)-0.274 i83.6(rO)-0.274 i83.6(rO)-0.274
Class T8 turbojet CO (g/kN) d           118 118
HC (g/kN) d         19.6 19.6 19.6
NOx (g/kN) d           j40 + 2(rPR) k32 + 1.6(rPR)
Smoke e30 e30 e30 e30 i83.6(rO)-0.274 i83.6(rO)-0.274 i83.6(rO)-0.274
Turbofan and turbojet engines other than Classes T3, T8, and TSS CO (g/kN) d           118 118
HC (g/kN) d         19.6 19.6 19.6
NOx (g/kN) d           j40 + 2(rPR) k32 + 1.6(rPR)
Smoke   f83.6(rO)-0.274 f83.6(rO)-0.274 g83.6(rO)-0.274 i83.6(rO)-0.274 i83.6(rO)-0.274 i83.6(rO)-0.274
TSS engines (supersonic aircraft engines) HC (g/kN)         rPR140(0.92) rPR140(0.92) rPR140(0.92)
Smoke         i83.6(rO)-0.274 rPR140(0.92) rPR140(0.92)

a Federal standards apply to all planes operating in the United States, regardless of where they were manufactured. This table primarily displays exhaust emissions standards for newly manufactured aircraft engines. Only two standards (smoke standards) have been set for in-use aircraft engines (see footnotes j and k). Therefore, unless otherwised noted, emissions in this table apply to new aircraft engines only.
b HC, CO, and NOx are measured using the International Civil Aviation Organization (ICAO) Gaseous Emissions Test Procedure. Smoke is measured using the ICAO Smoke Emission Test Procedure. There is no useful life or warranty period for purposes of compliance with emissions standards.
c Examples of commercial aircraft that use each engine type include the following: Class T3 turbojet--Boeing 707-320s (Class T3 engines are currently out of production, though some are still in use). Class T8 turbojet--Boeing 727s and 737-200s, and McDonnell-Douglas MD-80s and DC-9s. Turbofans and turbojets other than T3, T8, and TSS--Boeing 747-400s, 757s, 767-200s and 777s, and McDonnell-Douglas MD-11s; Canadair Regional Jets. Turboprops--Used mostly in regional airliners such as ATR 72, Dornier 328, and Saab SF 340. TSS--British Aircraft Corp./Aerospatiale Concorde (the only supersonic aircraft currently used in commercial civil aviation).
d rO >= 1,000 kW
e Applies to engines with rO>26.7 kN.
f Effective as of July 7, 1997. This standard applies only to those engines of a type or model for which the date of manufacture of the first individual production model was on or before Dec. 31, 1995 and for which the date of manufacture of the individual engine was on or before Dec. 31, 1999.
g Effective as of July 7, 1997. This standard also applies to engines of a type or model for which the date of manufacture of the first individual production model was after Dec. 31, 1995 and for which the date of manufacture of the individual engine was on or before Dec. 31, 1999.
h Engines with rO>=26.7 kN. Smoke number may not exceed 50.
i Engines manufactured after Feb. 1, 1974 and before 1984. This is also the in-use standard for all such aircraft engines manufactured after Feb. 1, 1974.
j Engines with rated output rO>=129 kN. This is also the in-use standard for all such aircraft engines.
k Engines with rO<26.7 kN. Smoke number may not exceed 50.

KEY: CO = carbon monoxide; g = gram; g/kN = grams of pollutant per kilonewtons of thrust; HC = hydrocarbon, kN = kilonewtons; kW = kilowatt; NOx = nitrogen oxides; rO = rated output, which is the maximum power or thrust available for takeoff; rPR = rated pressure ratio.

SOURCES: 40 CFR 87, Subparts A-D (July 1, 1998). Jane's Information Group Inc. 1992. Jane's All the World's Aircraft, 1992-93 (Alexandria, VA).

Updated: Saturday, May 20, 2017