14 CFR Part 34 — Fuel Venting and Exhaust Emission Requirements for Turbine Engine Powered Airplanes

Federal Aviation Administration, DOT Pt. 34

[Amdt. 33–34, 79 FR 65538, Nov. 4, 2014] 34.21 Standards for exhaust emissions.

34.23 Exhaust Emission Standards for En- gines Manufactured on and after July 18,

PART 34—FUEL VENTING AND EX-

2012.

HAUST EMISSION REQUIREMENTS

34.25 Non-volatile particulate emissions

FOR TURBINE ENGINE POWERED

standards (nvPM).

AIRPLANES

Subpart D—Exhaust Emissions (In-Use Subpart A—General Provisions Aircraft Gas Turbine Engines) Sec.

34.30 Applicability.

34.1 Definitions.

34.31 Standards for exhaust emissions.

34.2 Abbreviations.

34.3 General requirements.

Subpart E—Certification Provisions 34.4 Incorporation by reference.

34.5 Special test procedures.

34.48 Derivative engines for emissions cer- 34.6 Aircraft safety.

tification purposes.

34.7 Exemptions.

34.9 Exceptions.

Subpart F [ Reserved ] Subpart B—Engine Fuel Venting Emissions Subpart G—Test Procedures for Engine Ex- (New and In-Use Aircraft Gas Turbine haust Gaseous Emissions (Aircraft and Engines) Aircraft Gas Turbine Engines) 34.10 Applicability.

34.60 Introduction.

34.11 Standard for fuel venting emissions.

Subpart C—Exhaust Emissions (New Aircraft Gas Turbine Engines) 34.20 Applicability.

14 CFR Ch. I (1–1–25 Edition) § 34.1 34.61–34.71 [Reserved] otherwise would have been fulfilled by turbojet and turbofan engines except Subpart H—Test Procedures and Compli- engines of class T3, T8, and TSS.

ance Demonstration for Non-Volatile Class T3 means all aircraft gas tur- Particulate Matter Emissions bine engines of the JT3D model family.

34.71 Non-Volatile Particulate Matter Class T8 means all aircraft gas tur- (nvPM) Test Procedures.

bine engines of the JT8D model family.

34.73 Demonstration of compliance for Class TSS means all aircraft gas tur- nvPM emissions.

bine engines employed for propulsion A UTHORITY : 42 U.S.C. 4321 et seq., 7572; 49 of aircraft designed to operate at su- U.S.C. 106(g), 40113, 44701–44702, 44704, 44714.

personic flight speeds.

S OURCE : Docket No. 25613, 55 FR 32861, Aug.

Commercial aircraft engine means any 10, 1990, unless otherwise noted.

aircraft engine used or intended for use by an ‘‘air carrier’’ (including those en- Subpart A—General Provisions gaged in ‘‘intrastate air transpor- tation’’) or a ‘‘commercial operator’’ § 34.1 Definitions.

(including those engaged in ‘‘intrastate As used in this part, all terms not de- air transportation’’) as these terms are fined herein shall have the meaning defined in Title 49 of the United States given them in the Clean Air Act, as Code and Title 14 of the Code of Federal amended (42 U.S.C. 7401 et. seq.): Regulations.

Act means the Clean Air Act, as Commercial aircraft gas turbine engine amended (42 U.S.C. 7401 et. seq.).

means a turboprop, turbofan, or tur- Administrator means the Adminis- bojet commercial aircraft engine.

trator of the Federal Aviation Admin- Date of manufacture of an engine is istration or any person to whom he has the date the inspection acceptance delegated his authority in the matter records reflect that the engine is com- concerned.

plete and meets the FAA approved type Administrator of the EPA means the design.

Administrator of the Environmental Derivative engine for emissions certifi- Protection Agency and any other offi- cation purposes means an engine that is cer or employee of the Environmental similar in design to an engine that has Protection Agency to whom the au- demonstrated compliance with the ap- thority involved may be delegated.

plicable exhaust emission standards of Aircraft as used in this part means this part, as determined by the FAA, any airplane as defined in 14 CFR part and has a U.S. type certificate issued 1 for which a U.S. standard airworthi- in accordance with part 33 of this chap- ness certificate or equivalent foreign ter.

airworthiness certificate is issued.

Emission measurement system means Aircraft engine means a propulsion en- all of the equipment necessary to gine which is installed in, or which is transport the emission sample and manufactured for installation in, an measure the level of emissions. This in- aircraft.

cludes the sample system and the in- Aircraft gas turbine engine means a strumentation system.

turboprop, turbofan, or turbojet air- Engine model means all commercial craft engine.

aircraft turbine engines which are of Characteristic level has the meaning the same general series, displacement, given in Appendix 6 of ICAO Annex 16 and design characteristics and are ap- as of July 2008 (incorporated by ref- proved under the same type certificate.

erence, see § 34.4). The characteristic level is a calculated emission level for Excepted, as used in § 34.9, means an each pollutant based on a statistical engine that may be produced and sold assessment of measured emissions from that does not meet otherwise applica- multiple tests. ble standards. Excepted engines must Class TP means all aircraft turboprop conform to regulatory conditions speci- engines. fied for an exception in § 34.9. Excepted Class TF means all turbofan or tur- engines are subject to the standards of bojet aircraft engines or aircraft en- this part even though they are not re- gines designed for applications that quired to comply with the otherwise Federal Aviation Administration, DOT § 34.1 applicable requirements. Engines ex- or kilonewtons (as applicable), rounded cepted with respect to certain stand- to at least three significant figures.

ards must comply with other standards Rated pressure ratio (rPR) means the from which they are not specifically ratio between the combustor inlet pres- excepted.

sure and the engine inlet pressure Exempt means an engine that does achieved by an engine operation at not meet certain applicable standards rated output, rounded to at least three but may be produced and sold under significant figures.

the terms allowed by a grant of exemp- Reference day conditions means the tion issued pursuant to § 34.7 of this reference ambient conditions to which part and part 11 of this chapter. Ex- the measured smoke, nvPM, and gas- empted engines must conform to regu- eous emissions must be corrected. The latory conditions specified in the ex- reference day conditions are as follows: emption as well as other applicable (1) Temperature = 15 ° C, regulations. Exempted engines are sub- (2) Specific humidity = 0.00634 kg H O/ ject to the standards of this part even kg of dry air, and though they are not required to comply (3) Pressure = 101.325 kPa with the otherwise applicable require- ments. Engines exempted with respect Sample system means the system to certain standards must comply with which provides for the transportation other standards as a condition of the of the gaseous emission sample from exemption.

the sample probe to the inlet of the in- Exhaust emissions means substances strumentation system.

emitted into the atmosphere from the Shaft power means only the measured exhaust discharge nozzle of an aircraft shaft power output of a turboprop en- or aircraft engine.

gine.

In-use aircraft gas turbine engine Smoke means the matter in exhaust means an aircraft gas turbine engine emissions which obscures the trans- which is in service.

mission of light.

Introduction date means the date of Smoke number (SN) means the manufacture of the first individual pro- dimensionless term quantifying smoke duction engine of a given engine model emissions.

or engine type certificate family to be Standard day conditions means the certificated. Neither test engines nor following ambient conditions: tempera- engines not placed into service affect ture = 15 ° C, specific humidity = 0.00634 this date.

kg H O/kg dry air, and pressure = New aircraft turbine engine means an 101.325 kPa.

aircraft gas turbine engine which has Taxi/idle (in) means those aircraft op- never been in service.

erations involving taxi and idle be- Non-volatile particulate matter (nvPM) tween the time of landing roll-out and means emitted particles that remain at final shutdown of all propulsion en- the exhaust nozzle exit plane of a gas gines.

turbine engine, and that did not vola- Taxi/idle (out) means those aircraft tilize after being heated to a tempera- operations involving taxi and idle be- ture of at least 350 ° C.

tween the time of initial starting of Power setting means the power or the propulsion engine(s) used for the thrust output of an engine in terms of taxi and the turn onto the duty run- kilonewtons thrust for turbojet and way.

turbofan engines or shaft power in terms of kilowatts for turboprop en- Tier, as used in this part, is a des- gines. ignation related to the NO emission X Rated output (rO) means the max- standard for the engine as specified in imum power/thrust available for take- § 34.21 or § 34.23 of this part (e.g., Tier 0).

off at standard day conditions as ap- [Doc. No. 25613, 55 FR 32861, Aug. 10, 1990; 55 proved for the engine by the Federal FR 37287, Sept. 10, 1990, as amended by Amdt.

Aviation Administration, including re- 34–3, 64 FR 5558, Feb. 3, 1999; Amdt. 34–5, 77 heat contribution where applicable, but FR 76849, Dec. 31, 2012; Amdt. 34–5A, 78 FR excluding any contribution due to 63016, Oct. 23, 2013; Amdt. 34–7, 89 FR 31085, water injection, expressed in kilowatts Apr. 24, 2024] 14 CFR Ch. I (1–1–25 Edition) § 34.2 or equipment, the Administrator or the § 34.2 Abbreviations.

Administrator of the EPA shall consult The abbreviations used in this part with the other in determining whether have the following meanings in both or not the action requires rulemaking upper and lower case: under sections 231 and 232 of the Clean CO Carbon dioxide Air Act, as amended, consistent with CO Carbon monoxide the responsibilities of the Adminis- EPA United States Environmental trator of the EPA and the Secretary of Protection Agency Transportation under sections 231 and FAA Federal Aviation Administra- 232 of the Clean Air Act.

tion, United States Department of (b) Under section 232 of the Act, the Transportation Secretary of Transportation issues reg- g Gram(s) ulations to ensure compliance with 40 HC Hydrocarbon(s) CFR part 1031. This authority has been HP Horsepower delegated to the Administrator of the hr Hour(s) FAA in accordance with 49 CFR 1.47.

H O Water (c) This part applies to civil airplanes kg Kilogram(s) that are powered by aircraft gas tur- kJ Kilojoule(s) bine engines of the classes specified kN Kilonewton(s) herein and that have U.S. standard air- kW Kilowatt(s) worthiness certificates.

lbf Pound force (d) Pursuant to the definition of LTO Landing and takeoff ‘‘aircraft’’ in 40 CFR 1031.205, this regu- m Meter(s) lation applies to civil airplanes that mg Milligram(s) are powered by aircraft gas turbine en- μ g Microgram(s) gines of the classes specified herein and min Minute(s) that have foreign airworthiness certifi- MJ Megajoule(s) cates that are equivalent to U.S. stand- NO Oxides of nitrogen X ard airworthiness certificates. This nvPM Non-volatile particulate matter regulation applies only to those foreign nvPM Non-volatile particulate mass civil airplanes that, if registered in the matter mass United States, would be required by ap- nvPM Non-volatile particulate mat- MC plicable regulations to have a U.S.

ter mass concentration standard airworthiness certificate in nvPM Non-volatile particulate num order to conduct the operations in- matter number tended for the airplane. Pursuant to 40 Pa Pascal(s) CFR 1031.5, this regulation does not rO Rated output apply where it would be inconsistent rPR Rated pressure ratio with an obligation assumed by the sec Second(s) United States to a foreign country in a SP Shaft power treaty, convention, or agreement.

SN Smoke number (e) Reference in this regulation to 40 T Temperature in degrees Kelvin CFR part 1031 refers to title 40 of the TIM Time in mode Code of Federal Regulations, chapter ° C Degrees Celsius I—Environmental Protection Agency, % Percent part 1031, Control of Air Pollution from [Doc. No. FAA–2023–2434, Amdt. 34–7, 89 FR Aircraft and Aircraft Engines (40 CFR 31085, Apr. 24, 2024] part 1031).

(f) This part contains regulations § 34.3 General requirements.

that implement compliance with cer- (a) This part provides for the ap- tain standards contained in 40 CFR proval or acceptance by the Adminis- part 1031. If EPA takes any action, in- trator or the Administrator of the EPA cluding the issuance of an exemption of testing and sampling methods, ana- or issuance of a revised or alternate lytical techniques, and related equip- procedure, test method, or other regu- ment not identical to those specified in lation, the effect of which is to relax or this part. Before either approves or ac- delay the effective date of any provi- cepts any such alternate, equivalent, sion of 40 CFR part 1031 that is made or otherwise nonidentical procedures applicable to an aircraft under this

Federal Aviation Administration, DOT § 34.4 part, the Administrator of FAA will no state or political subdivision thereof grant a general administrative waiver may adopt or attempt to enforce the of the more stringent requirements terms of this part that are superseded until this part is amended to reflect by the relaxed requirement.

the requirements relaxed by EPA.

(n) If any provision of this part is (g) Unless otherwise stated, all ter- rendered inapplicable to a foreign air- minology and abbreviations in this craft as provided in 40 CFR 1031.5 part that are defined in 40 CFR part (international agreements), and para- 1031 have the meaning specified in that graph (d) of this section, that provision part, and all terms in 40 CFR part 1031 may not be adopted or enforced against that are not defined in that part but that foreign aircraft by a state or po- that are used in this part have the litical subdivision thereof.

meaning given them in the Clean Air (o) For exhaust emissions require- Act, Public Law 91–604, as amended.

ments of this part that apply beginning (h) All interpretations of 40 CFR part February 1, 1974, January 1, 1976, Janu- 1031 that are promulgated by the EPA ary 1, 1978, January 1, 1984, and August also apply to this part.

9, 1985, continued compliance with (i) If the EPA, under 40 CFR part those requirements is shown for en- 1031, approves or accepts any testing gines for which the type design has and sampling procedures or methods, been shown to meet those require- analytical techniques, or related equip- ments, if the engine is maintained in ment not identical to those specified in accordance with applicable mainte- that part, this part requires an appli- nance requirements of 14 CFR chapter cant to show that such alternate, I. All methods of demonstrating com- equivalent, or otherwise non-identical pliance and all model designations pre- procedures have been complied with, viously found acceptable to the Admin- and that such alternate equipment was istrator shall be deemed to continue to used to show compliance, unless the be an acceptable demonstration of applicant elects to comply with those compliance with the specific standards procedures, methods, techniques, and for which they were approved.

equipment specified in 40 CFR part (p) Each applicant must allow the 1031.

Administrator to make, or witness, (j) If the EPA, under 40 CFR 1031, pre- any test necessary to determine com- scribes special test procedures for any pliance with the applicable provisions aircraft or aircraft engine that is not of this part.

susceptible to satisfactory testing [Doc. No. FAA–2023–2434, Amdt. 34–7, 89 FR using the procedures in 40 CFR part 31085, Apr. 24, 2024] 1031, the applicant must demonstrate to the FAA Administrator that they § 34.4 Incorporation by Reference.

are in compliance with those special Certain material is incorporated by test procedures.

reference into this part with the ap- (k) Wherever 40 CFR part 1031 re- proval of the Director of the Federal quires agreement, acceptance, or ap- Register under 5 U.S.C. 552(a) and 1 proval by the Administrator of the CFR part 51). All approved material is EPA, this part requires a showing that available for inspection at the FAA and such agreement or approval has been at the National Archives and Records obtained.

Administration (NARA). Contact the (l) Pursuant to 42 U.S.C. 7573, no FAA Office of Rulemaking (ARM), 800 state or political subdivision thereof Independence Avenue SW, Washington, may adopt or attempt to enforce any DC 20590 (telephone 202–267–9677) For in- standard respecting emissions of any formation on the availability of this air pollutant from any aircraft or en- material at NARA, visit gine thereof unless that standard is www.archives.gov/federal-register/cfr/ibr- identical to a standard made applicable locations or email to the aircraft by the terms of this fr.inspection@nara.gov.

part.

(m) If EPA, by regulation or exemp- (a) The material may be obtained tion, relaxes a provision of 40 CFR part from the following source: Inter- 1031 that is implemented in this part, national Civil Aviation Organization 14 CFR Ch. I (1–1–25 Edition) § 34.5 (ICAO): Document Sales Unit, 999 Uni- by the EPA that is incorporated in this versity Street, Montreal, Quebec H3C FAR, or the compliance date for such 5H7, Canada, phone + 1 514–954–8022, or standard or procedure, must be sub- www.icao.int. mitted to the EPA. Information copies (1) Annex 16 to the Convention on of such petitions are invited by the International Civil Aviation: Environ- FAA. Petitions for rulemaking or ex- mental Protection, Volume II—Air- emption involving provisions of this craft Engine Emissions, Third Edition, FAR that do not affect the substance July 2008 (ICAO Annex 16); in §§ 34.1 and or the compliance date of an emission 34.60.

standard or test procedure that is pre- (2) Annex 16 to the Convention on scribed by the EPA, and petitions for International Civil Aviation: Environ- exemptions under the provisions for mental Protection, Volume II—Air- which the EPA has specifically granted craft Engine Emissions, Fourth Edi- exemption authority to the Secretary tion, July 2017 (ICAO Annex 16, Volume of Transportation are subject to part 11 II), in §§ 34.71 and 34.73.

of the Federal Aviation Regulations (14 (b) [Reserved] CFR part 11). Petitions for rulemaking or exemptions involving these FARs [Doc. No. FAA–2023–2434, Amdt. 34–7, 89 FR must be submitted to the FAA.

31086, Apr. 24, 2024] (a) Exemptions based on flights for § 34.5 Special test procedures.

short durations at infrequent intervals.

The emission standards of this part do The Administrator or the Adminis- not apply to engines which power air- trator of the EPA may, upon written craft operated in the United States for application by a manufacturer or oper- short durations at infrequent intervals.

ator of aircraft or aircraft engines, ap- Such operations are limited to: prove test procedures for any aircraft (1) Flights of an aircraft for the pur- or aircraft engine that is not suscep- pose of export to a foreign country, in- tible to satisfactory testing by the pro- cluding any flights essential to dem- cedures set forth herein. Prior to tak- onstrate the integrity of an aircraft ing action on any such application, the prior to a flight to a point outside the Administrator or the Administrator of the EPA shall consult with the other. United States.

(2) Flights to a base where repairs, § 34.6 Aircraft safety.

alterations or maintenance are to be (a) The provisions of this part will be performed, or to a point of storage, or revised if at any time the Adminis- for the purpose of returning an aircraft trator determines that an emission to service.

standard cannot be met within the (3) Official visits by representatives specified time without creating a safe- of foreign governments.

ty hazard.

(4) Other flights the Administrator (b) Consistent with 40 CFR part 1031, determines, after consultation with the if the FAA Administrator determines Administrator of the EPA, to be for that any emission control regulation in short durations at infrequent intervals.

this part cannot be safely applied to an A request for such a determination aircraft, that provision may not be shall be made before the flight takes adopted or enforced against that air- place.

craft by any state or political subdivi- (b) Exemptions for very low production sion thereof.

engine models. The emissions standards of this part do not apply to engines of [Docket No. 25613, 55 FR 32861, Aug. 10, 1990, as amended by Amdt. No. 34–7, 89 FR 31086, very low production after the date of Apr. 24, 2024] applicability. For the purpose of this part, ‘‘very low production’’ is limited § 34.7 Exemptions.

to a maximum total production for Notwithstanding part 11 of the Fed- United States civil aviation applica- eral Aviation Regulations (14 CFR part tions of no more than 200 units covered 11), all petitions for rulemaking involv- by the same type certificate after Jan- ing either the substance of an emission uary 1, 1984. Engines manufactured standard or test procedure prescribed under this provision must be reported Federal Aviation Administration, DOT § 34.10 to the FAA by serial number on or be- § 34.9 Exceptions.

fore the date of manufacture and ex- (a) Spare engines. Certain engines emptions granted under this provision that meet the following description are are not transferable to any other en- excepted: gine. This exemption is limited to the (1) This exception allows production requirements of § 34.21 only.

of an engine for installation on an in- (c) Exemptions for new engines in other service aircraft. A spare engine may categories. The emissions standards of not be installed on a new aircraft.

(2) Each spare engine must be iden- this part do not apply to engines for tical to a sub-model previously certifi- which the Administrator determines, cated to meet all applicable require- with the concurrence of the Adminis- ments.

trator of the EPA, that application of (3) A spare engine may be used only any standard under § 34.21 is not justi- when the emissions of the spare do not fied, based upon consideration of— exceed the certification requirements (1) Adverse economic impact on the of the original engine, for all regulated manufacturer; pollutants.

(2) Adverse economic impact on the (4) No separate approval is required aircraft and airline industries at large; to produce spare engines.

(3) Equity in administering the (5) The record for each engine ex- standards among all economically cepted under this paragraph (c) must competing parties; indicate that the engine was produced (4) Public health and welfare effects; as an excepted spare engine.

and (6) Engines produced under this ex- ception must be labeled ‘‘EXCEPTED (5) Other factors which the Adminis- SPARE’’ in accordance with § 45.13 of trator, after consultation with the Ad- this chapter.

ministrator of the EPA, may deem rel- (b) On and after July 18, 2012, and be- evant to the case in question.

fore August 31, 2013, a manufacturer (d) Applicants seeking exemption from may produce up to six Tier 4 compliant other emissions standards of this part and engines that meet the NO standards of X 40 CFR 1031.15. Applicants must request paragraph (d)(1)(vi) of this section exemption from both the FAA and the rather than § 34.23(a)(2). No separate ap- EPA, even where the underlying regu- proval is required to produce these en- latory requirements are the same. The gines. Engines produced under this ex- FAA and EPA will jointly consider ception are to be labeled ‘‘COMPLY’’ in such exemption requests, and will as- accordance with § 45.13 of this chapter.

sure consistency in the respective [Doc. No. FAA–2012–1333, 77 FR 76850, Dec. 31, agency determinations.

2012] (e) Applications for exemption from this part shall be submitted in dupli- Subpart B—Engine Fuel Venting cate to the Administrator in accord- Emissions (New and In-Use ance with the procedures established Aircraft Gas Turbine Engines) by the Administrator in part 11.

(f) The Administrator shall publish in § 34.10 Applicability.

the F EDERAL R EGISTER the name of the (a) The provisions of this subpart are organization to whom exemptions are applicable to all new aircraft gas tur- granted and the period of such exemp- bine engines of classes T3, T8, TSS, and tions.

TF equal to or greater than 36 kN (8,090 (g) No state or political subdivision lb) rated output, manufactured on or thereof may attempt to enforce a after January 1, 1974, and to all in-use standard respecting emissions from an aircraft gas turbine engines of classes aircraft or engine if such aircraft or en- T3, T8, TSS, and TF equal to or greater gine has been exempted from such than 36 kN (8,090 lb) rated output man- standard under this part.

ufactured after February 1, 1974.

(b) The provisions of this subpart are [Doc. No. 25613, 55 FR 32861, Aug. 10, 1990, as also applicable to all new aircraft gas amended by Amdt. 34–5, 77 FR 76850, Dec. 31, 2012; Amdt. 34–7, 89 FR 31087, Apr. 24, 2024] turbine engines of class TF less than 36 14 CFR Ch. I (1–1–25 Edition) § 34.11 kN (8,090 lb) rated output and class TP gines of the classes specified beginning manufactured on or after January 1, on the dates specified in § 34.21.

1975, and to all in-use aircraft gas tur- § 34.21 Standards for exhaust emis- bine engines of class TF less than 36 kN sions.

(8,090 lb) rated output and class TP manufactured after January 1, 1975.

(a) Exhaust emissions of smoke from each new aircraft gas turbine engine of [Doc. No. FAA–2012–1333, 77 FR 76850, Dec. 31, class T8 manufactured on or after Feb- 2012] ruary 1, 1974, shall not exceed a smoke number (SN) of 30.

§ 34.11 Standard for fuel venting emis- sions.

(b) Exhaust emissions of smoke from each new aircraft gas turbine engine of (a) No liquid fuel venting emissions class TF and of rated output of 129 kN shall be discharged into the atmos- (29,000 lb) thrust or greater, manufac- phere from any new or in-use aircraft tured on or after January 1, 1976, shall gas turbine engine subject to the sub- not exceed part. This paragraph is directed at the ¥ 0.274 elimination of intentional discharge to SN = 83.6 (rO) (rO is in kN).

the atmosphere of fuel drained from (c) Exhaust emission of smoke from fuel nozzle manifolds after engines are each new aircraft gas turbine engine of shut down and does not apply to nor- class T3 manufactured on or after Jan- mal fuel seepage from shaft seals, uary 1, 1978, shall not exceed a smoke joints, and fittings.

number (SN) of 25.

(b) Conformity with the standard set (d) Gaseous exhaust emissions from forth in paragraph (a) of this section each new aircraft gas turbine engine shall be determined by inspection of shall not exceed: the method designed to eliminate these (1) For Classes TF, T3, T8 engines emissions.

greater than 26.7 kN (6,000 lb) rated (c) As applied to an airframe or an output: engine, any manufacturer or operator (i) Engines manufactured on or after may show compliance with the liquid January 1, 1984: fuel venting and emissions require- ments of this section that were effec- Hydrocarbons: 19.6 g/kN rO.

tive beginning February 1, 1974 or Jan- (ii) Engines manufactured on or after uary 1, 1975, by any means that pre- July 7, 1997: vents the intentional discharge of fuel Carbon Monoxide: 118 g/kN rO.

from fuel nozzle manifolds after the en- gines are shut down. Acceptable means (iii) Engines of a type or model of of compliance include one of the fol- which the date of manufacture of the lowing: first individual production model was (1) Incorporation of an FAA-approved on or before December 31, 1995, and for system that recirculates the fuel back which the date of manufacture of the into the fuel system.

individual engine was on or before De- (2) Capping or securing the pressur- cember 31, 1999 (Tier 2): ization and drain valve.

Oxides of Nitrogen: (40 + 2(rPR)) g/kN (3) Manually draining the fuel from a rO.

holding tank into a container.

(iv) Engines of a type or model of [Docket No. 25613, 55 FR 32861, Aug. 10, 1990, which the date of manufacture of the as amended by Amdt. No. 34–7, 89 FR 31087, first individual production model was Apr. 24, 2024] after December 31, 1995, or for which the date of manufacture of the indi- Subpart C—Exhaust Emissions vidual engine was after December 31, (New Aircraft Gas Turbine En- 1999 (Tier 2): gines) Oxides of Nitrogen: (32 + 1.6(rPR)) g/kN § 34.20 Applicability. rO.

The provisions of this subpart are ap- (v) The emission standards prescribed plicable to all aircraft gas turbine en- in paragraphs (d)(1)(iii) and (iv) of this

Federal Aviation Administration, DOT § 34.21 ¥ 0.274 section apply as prescribed beginning SN = 83.6(rO) or 50.0, whichever is July 7, 1997. smaller.

(vi) The emission standards of this (C) For Classes TF, T3, and T8 of paragraph apply as prescribed after De- rated output of 26.7 kN (6,000 lbf) or less cember 18, 2005. For engines of a type manufactured on or after January 1, or model of which the first individual 2023: production model was manufactured ¥ 0.274 SN = 83.6(rO) or 50.0, whichever is after December 31, 2003 (Tier 4): smaller.

(A) That have a rated pressure ratio of 30 or less and a maximum rated out- (2) For Classes T3, T8, TSS, and TF of put greater than 89 kN: rated output greater than or equal to- 26.7 kN (6,000 lbf) manufactured on or Oxides of Nitrogen: (19 + 1.6(rPR)) g/kN after January 1, 1984, and before Janu- rO.

ary 1, 2023: (B) That have a rated pressure ratio ¥ 0.274 SN = 83.6(rO) (rO is in kN) not to of 30 or less and a maximum rated out- exceed a maximum of SN = 50.

put greater than 26.7 kN but not great- (3) For Class TP of rated output er than 89 kN: equal to or greater than 1,000 kW man- Oxides of Nitrogen: (37.572 + 1.6(rPR) ¥ ufactured on or after January 1, 1984: 0.2087(rO)) g/kN rO.

¥ 0.168 SN = 187(rO) (rO is in kW).

(C) That have a rated pressure ratio (4) For Class TSS manufactured on or greater than 30 but less than 62.5, and after January 1, 2023: a maximum rated output greater than ¥ 0.274 SN = 83.6(rO) (rO is in kN) not to 89 kN: exceed a maximum of SN = 50.

Oxides of Nitrogen: (7 + 2(rPR)) g/kN (f) The standards set forth in para- rO.

graphs (a), (b), (c), (d), and (e) of this (D) That have a rated pressure ratio section refer to a composite gaseous greater than 30 but less than 62.5, and emission sample representing the oper- a maximum rated output greater than ation cycles and exhaust smoke emis- 26.7 kN but not greater than 89 kN: sion emitted during operation of the Oxides of Nitrogen: (42.71 + 1.4286(rPR) engine as specified in the applicable ¥ 0.4013(rO) + 0.00642(rPR × rO)) g/ sections of subpart G of this part, and kN rO.

measured and calculated in accordance with the procedures set forth in sub- (E) That have a rated pressure ratio part G.

of 62.5 or more: (g) Where a gaseous emission stand- Oxides of Nitrogen: (32 + 1.6(rPR)) g/kN ard is specified by a formula, calculate rO.

and round the standard to three signifi- (2) For Class TSS Engines manufac- cant figures or to the nearest 0.1 g/kN tured on or after January 1, 1984: (for standards at or above 100 g/kN).

Where a smoke standard is specified by rPR Hydrocarbons: 140 (0.92) g/kN rO.

a formula, calculate and round the (e) Smoke exhaust emissions from standard to the nearest 0.1 SN. Engines each gas turbine engine shall not ex- comply with an applicable standard if ceed: the testing results show that the en- (1)(A) For Class TF of rated output gine type certificate family’s char- less than 26.7 kN (6,000 lbf) manufac- acteristic level does not exceed the nu- tured on or after August 9, 1985, and be- merical level of that standard, as de- fore July 18, 2012: scribed in § 34.60.

¥ 0.274 SN = 83.6(rO) (rO is in kN) not to [Doc. No. 25613, 55 FR 32861, Aug. 10, 1990; 55 exceed a maximum of SN = 50.

FR 37287, Sept. 10, 1990, as amended by Amdt.

(B) For Classes TF, T3, and T8 of 34–3, 64 FR 5559, Feb. 3, 1999; Amdt. 34–4, 74 rated output less than 26.7 kN (6,000 lbf) FR 19127, Apr. 28, 2009; Amdt. 34–5, 77 FR manufactured on or after July 18, 2012, 76851, Dec. 31, 2012; Amdt. No. 34–7, 89 FR and before January 1, 2023: 31087, Apr. 24, 2024] 14 CFR Ch. I (1–1–25 Edition) § 34.23 show that the engine type certificate § 34.23 Exhaust Emission Standards for Engines Manufactured on and family’s characteristic level does not after July 18, 2012.

exceed the numerical level of that standard, as described in § 34.60.

The standards of this section apply to aircraft engines manufactured on (a) Gaseous exhaust emissions from and after July 18, 2012, unless otherwise each new aircraft gas turbine engine exempted or excepted. Where a gaseous shall not exceed: emission standard is specified by a for- (1) [Reserved] mula, calculate and round the standard (2) Except as provided in §§ 34.9(b) and to three significant figures or to the 34.21(c), for Classes TF, T3 and T8 en- nearest 0.1 g/kN (for standards at or gines manufactured on and after July above 100 g/kN). Where a smoke stand- 18, 2012, and for which the first indi- ard is specified by a formula, calculate vidual production model was manufac- and round the standard to the nearest tured on or before December 31, 2013 0.1 SN. Engines comply with an appli- (Tier 6): cable standard if the testing results T IER 6 O XIDES OF NITROGEN EMISSION STANDARDS FOR S UBSONIC E NGINES Rated pressure ratio— Rated output rO NO X Class rPR (kN) (g/kN) TF, T3, T8 ..................... rPR ≤ 30 ....................... 26.7 < rO ≤ 89.0 ........... 38.5486 + 1.6823 (rPR) ¥ 0.2453 (rO) ¥ (0.00308 (rPR) (rO)).

rO > 89.0 ...................... 16.72 + 1.4080 (rPR).

30 < rPR < 82.6 ........... 26.7 < rO ≤ 89.0 ........... 46.1600 + 1.4286 (rPR) ¥ 0.5303 (rO) + (0.00642 (rPR) (rO)).

rO > 89.0 ...................... ¥ 1.04 + 2.0 (rPR).

rPR ≥ 82.6 .................... rO ≥ 26.7 ...................... 32 + 1.6 (rPR).

(3) Engines exempted from paragraph the requirements of paragraph (a)(2) of (a)(2) of this section produced on or be- this section will be granted after De- fore December 31, 2016 must be labeled cember 31, 2016.

‘‘EXEMPT NEW’’ in accordance with (4) For Class TSS Engines manufac- § 45.13 of this chapter. No exemptions to tured on and after July 18, 2012: G ASEOUS E MISSION STANDARDS FOR S UPERSONIC E NGINES Rated output NO CO X Class rO (kN) (g/kN) (g/kN) ¥ 1.03 TSS .......................................... All ............................................ 36 + 2.42 (rPR) ..................... 4,550 (rPR) rO is the rated output with afterburning applied.

(b) Gaseous exhaust emissions from dividual production model was manu- each new aircraft gas turbine engine factured after December 31, 2013 (Tier shall not exceed: 8): (1) For Classes TF, T3 and T8 engines of a type or model of which the first in- T IER 8 O XIDES OF NITROGEN EMISSION STANDARDS FOR S UBSONIC E NGINES Rated pressure ratio— Rated output rO NO X Class rPR (kN) (g/kN) TF, T3, T8 ..................... rPR ≤ 30 ....................... 26.7 < rO ≤ 89.0 ........... 40.052 + 1.5681 (rPR) ¥ 0.3615 (rO) ¥ (0.0018 (rPR) (rO)).

rO > 89.0 ...................... 7.88 + 1.4080 (rPR).

Federal Aviation Administration, DOT § 34.25 T IER 8 O XIDES OF NITROGEN E MISSION S TANDARDS FOR S UBSONIC E NGINES —Continued Rated pressure ratio— Rated output rO NO X Class rPR (kN) (g/kN) 30 < rPR < 104.7 ......... 26.7 < rO ≤ 89.0 ........... 41.9435 + 1.505 (rPR) ¥ 0.5823 (rO) + (0.005562 (rPR) (rO)).

rO > 89.0 ...................... ¥ 9.88 + 2.0 (rPR).

rPR ≥ 104.7 .................. rO ≥ 26.7 ...................... 32 + 1.6 (rPR).

(c) Engines (including engines that to the nearest 1.0 μ g/m . Where an are determined to be derivative engines nvPM standard is expressed as a for- mass for the purposes of emission certifi- mula, calculate and round the standard cation) type certificated with char- to three significant figures or to the acteristic levels at or below the NO nearest 0.1 mg/kN. Where an nvPM X num standards of § 34.21(d)(1)(vi) of this part standard is expressed as a formula, cal- (as applicable based on rated output culate and round the standard to three and rated pressure ratio) and intro- significant figures. Engines comply duced before July 18, 2012, may be pro- with an applicable standard if the test duced through December 31, 2012, with- results show that the engine type cer- out meeting the NO standard of para- X tificate family’s characteristic level graph (a)(2) of this section.

does not exceed the numerical level of the nvPM standard when tested as de- [Doc. No. 34–5, 77 FR 76851, Dec. 31, 2012, as scribed in subpart H of this part.

amended by Amdt. 34–5A, 78 FR 63017, Oct. 23, 2013; 78 FR 65554, Nov. 1, 2013; Amdt. No. 34– (a) Except as provided in paragraph 7, 89 FR 31087, Apr. 24, 2024] (b) or (c) of this section; (1) The characteristic level for the § 34.25 Non-volatile particulate emis- maximum nvPM expressed in units MC sions standards (nvPM).

of μ g/m must not exceed the following: The standards of this section apply –0.274 ( 3 ∂ 2.9 r0 ) nvPM = 10 MC to an aircraft engine of Class TF, T3, or T8 with a rated output greater than and 26.7 kN that is manufactured after Jan- (2) The characteristic level for nvPM uary 1, 2023. Where a maximum mass expressed in [mg/kN] and for nvPM standard is expressed as a for- nvPM number expressed in [particles/ MC mula, calculate and round the standard kN] must not exceed the following: T ABLE 1 TO P ARAGRAPH (a)(2) Rated output nvPM nvPM mass num Class (rO) (mg/kN) (particles/kN) (kN) 16 14 TF, T3, T8 ................................ 26.7 < rO ≤ 200 ..................... 4646.9 ¥ 21.497 (rO) ............ 2.669 × 10 ¥ 1.126 × 10 (rO).

rO > 200 ................................. 347.5 ...................................... 4.170 × 10 .

(b) For a change in type design by (2) If the engine does not qualify as a the type design holder, when the appli- derivative engine in accordance with cation for an amended type certificate § 34.48 of this part, the applicant must is filed after January 1, 2023: demonstrate compliance with each re- (1) If the engine qualifies as a deriva- quirement in paragraph (a) of this sec- tion.

tive engine in accordance with § 34.48 of this part, no testing is required for the (c) For issuance of an original type engine to use the same nvPM certifi- certificate when an application for cated parameters (nvPM , nvPM , type certification is filed after January mass num and maximum nvPM ) as the engine 1, 2023, the applicant must demonstrate MC it is derived from; or that the engine does not exceed: 14 CFR Ch. I (1–1–25 Edition) § 34.30 (1) For maximum nvPM : as pre- (2) For the characteristic level for MC scribed in paragraph (a)(1) of this sec- nvPM expressed in units of [mg/kN], mass and for nvPM expressed in units of tion; and num [particles/kN], the following: T ABLE 2 TO P ARAGRAPH (c)(2) Rated output nvPM nvPM mass num Class (rO) (mg/kN) (particles/kN) (kN) 16 13 TF, T3, T8 ................................ 26.7 < rO ≤ 150 ..................... 1251.1 ¥ 6.914 (rO) .............. 1.490 × 10 ¥ 8.080 × 10 (rO).

rO > 150 ................................. 214.0 ...................................... 2.780 × 10 .

(d) For engines type certificated Subpart E—Certification Provisions after January 1, 2023 and prior to May 24, 2024, compliance with this part § 34.48 Derivative engines for emis- sions certification purposes.

must be demonstrated no later than August 22, 2024.

(a) General. A type certificate holder may request from the FAA a deter- [Doc. No. FAA–2023–2434, Amdt. No. 34–7, 89 mination that an engine configuration FR 31087, Apr. 24, 2024, as amended by Amdt.

is considered a derivative engine for No. 34–7A, 89 FR 37972, May 7, 2024] emissions certification purposes (all gaseous emissions and either nvPM or Subpart D—Exhaust Emissions (In- smoke number as applicable). To be use Aircraft Gas Turbine Engines) considered a derivative engine for emissions certification purposes under § 34.30 Applicability.

this part, the configuration must have The provisions of this subpart are ap- been derived from the original engine plicable to all in-use aircraft gas tur- that was certificated to the require- bine engines certificated for operation ments of part 33 of this chapter and one within the United States of the classes of the following: specified, beginning on the dates speci- (1) The FAA has determined that a fied in § 34.31.

safety issue exists that requires an en- gine modification.

§ 34.31 Standards for exhaust emis- (2) Emissions from the derivative en- sions.

gines are determined to be similar. In (a) Exhaust emissions of smoke from general, this means the emissions must each in-use aircraft gas turbine engine meet the criteria specified in para- of Class T8, beginning February 1, 1974, graph (b) of this section. The FAA may shall not exceed a smoke number (SN) amend the criteria of paragraph (b) in of 30.

unusual circumstances, for individual (b) Exhaust emissions of smoke from cases, consistent with good engineering each in-use aircraft gas turbine engine judgment.

of Class TF and of rated output of 129 (3) All of the regulated emissions kN (29,000 lb) thrust or greater, begin- from the derivative engine are lower ning January l, 1976, shall not exceed than the original engine.

¥ (b) Emission similarity (1) The type 0.274 SN = 83.6(rO) (rO is in kN).

certificate holder must demonstrate (c) The standards set forth in para- that the proposed derivative engine graphs (a) and (b) of this section refer model’s emissions meet the applicable to exhaust smoke emission emitted standards and differ from the original during operation of the engine as speci- model’s emission rates within the fol- fied in the applicable sections of sub- lowing ranges and values: part G of this part, and measured and (i) ± 3.0 g/kN for NO .

X calculated in accordance with the pro- (ii) ± 1.0 g/kN for HC.

cedures set forth in subpart G.

(iii) ± 5.0 g/kN for CO.

(iv) ± 2.0 SN for smoke (where applica- [Doc. No. FAA–2012–1333, 77 FR 76852, Dec. 31, 2012] ble).

Federal Aviation Administration, DOT § 34.60 (v) The following values apply for (c) Continued production allowance.

maximum nvPM , nvPM , and Derivative engines for emissions cer- MC mass nvPM (where applicable): tification purposes may continue to be num (A) maximum nvPM : produced after the applicability date MC ( 1 ) ± 200 μ g/m3 if the characteristic for new emissions standards when the level of maximum nvPM is below engines conform to the specifications MC 1,000 μ g/m ; or of this section.

( 2 ) ± 20% of the characteristic level if (d) Non-derivative engines. If the FAA the characteristic level for maximum determines that an engine model does nvPM is at or above 1,000 μ g/m . not meet the requirements for a deriva- MC (B) nvPM : tive engine for emissions certification mass ( 1 ) 80 mg/kN if the characteristic purposes, the type certificate holder is level for nvPM emissions is below required to demonstrate that the en- mass 400 mg/kN; or gine complies with the emissions ( 2 ) ± 20% of the characteristic level if standards applicable to a new engine the characteristic level for nvPM type.

mass emissions is greater than or equal to [Doc. No. 34–5, 77 FR 76852, Dec. 31, 2012, as 400 mg/kN.

amended by Amdt. No. 34–7, 89 FR 31088, Apr.

(C) nvPM : num 24, 2024] ( 1 ) 4 × 10 particles/kN if the char- acteristic level for nvPM emissions num Subpart F [ Reserved ] is below 2 × 10 particles/kN; or ( 2 ) ± 20% of the characteristic level if Subpart G—Test Procedures for the characteristic level for nvPM num Engine Exhaust Gaseous Emis- emissions is greater than or equal to 2 15 sions (Aircraft and Aircraft × 10 particles/kN.

Gas Turbine Engines) (2) If the characteristic level of the original certificated engine model (or § 34.60 Introduction.

any other sub-models within the emis- sion type certificate family tested for (a) Use the equipment and procedures certification) before modification is at specified in Appendix 3, Appendix 5, or above 95% of the applicable standard and Appendix 6 of ICAO Annex 16, as for any pollutant, an applicant must applicable, to demonstrate whether en- measure the proposed derivative engine gines meet the applicable gaseous model’s emissions for all pollutants to emission standards specified in subpart demonstrate that the derivative en- C of this part. Measure the emissions of gine’s resulting characteristic levels all regulated gaseous pollutants. Use will not exceed the applicable emission the equipment and procedures specified standards. If the characteristic levels in Appendix 2 and Appendix 6 of ICAO of the originally certificated engine Annex 16 to determine whether engines model (and all other sub-models within meet the applicable smoke standard the emission type certificate family specified in subpart C of this part. The tested for certification) are below 95% compliance demonstration consists of of the applicable standard for each pol- establishing a mean value from testing lutant, the applicant may use engineer- the specified number of engines, then ing analysis consistent with good engi- calculating a ‘‘characteristic level’’ by neering judgment to demonstrate that applying a set of statistical factors the derivative engine will not exceed that take into account the number of the applicable emission standards. The engines tested. Round each char- engineering analysis must address all acteristic level to the same number of modifications from the original engine, decimal places as the corresponding including those approved for previous emission standard. For turboprop en- derivative engines. gines, use the procedures specified for (3) In unusual circumstances and con- turbofan engines, consistent with good sistent with good engineering judge- engineering judgment.

ment, the FAA may adjust the ranges (b) Use a test fuel that meets the specified in paragraph (b)(1) of this sec- specifications described in Appendix 4 tion to evaluate a proposed derivative of ICAO Annex 16. The test fuel must engine. not have additives whose purpose is to 14 CFR Ch. I (1–1–25 Edition) §§ 34.61–34.71 suppress smoke, such as specifications that differ from those organometallic compounds. specified in this part. Manufacturers (c) Prepare test engines by including and operators may request approval of accessories that are available with pro- alternative procedures by written re- duction engines if they can reasonably quest with supporting justification to be expected to influence emissions. The the FAA and to the Designated EPA test engine may not extract shaft Program Officer. To be approved, one power or bleed service air to provide of the following conditions must be power to auxiliary gearbox-mounted met: components required to drive aircraft (1) The engine cannot be tested using systems. the specified procedures; or (d) Test engines must reach a steady (2) The alternative procedure is operating temperature before the start shown to be equivalent to, or more ac- of emission measurements. curate or precise than, the specified (e) In consultation with the EPA, the procedure.

FAA may approve alternative proce- (f) The following landing and takeoff dures for measuring emissions, includ- (LTO) cycles apply for emissions test- ing testing and sampling methods, ana- ing and for calculating weighted LTO lytical techniques, and equipment values: LTO T EST C YCLES AND T IME IN M ODE Class Mode TP TF, T3, T8 TSS TIM (min) % of rO TIM (min) % of rO TIM (min) % of rO Taxi/idle ................................................. 26.0 7 26.0 7 26.0 5.8 Takeoff .................................................. 0.5 100 0.7 100 1.2 100 Climbout ................................................ 2.5 90 2.2 85 2.0 65 Descent ................................................. NA NA NA NA 1.2 15 Approach ............................................... 4.5 30 4.0 30 2.3 34 (g) Engines comply with an applica- §§ 34.61–34.71 [Reserved] ble standard if the testing results show that the engine type certificate fam- Subpart H—Test Procedures and ily’s characteristic level does not ex- Compliance Demonstration ceed the numerical level of that stand- for Non-Volatile Particulate ard, as described in the applicable ap- Matter Emissions pendix of Annex 16.

(h) The system and procedure for S OURCE : Doc. No. FAA–2023–2434; Amdt. No.

sampling and measurement of gaseous 34–7, 89 FR 31088, Apr. 24, 2024, unless other- emissions shall be as specified by in wise noted.

Appendices 2, 3, 4, 5 and 6 to the Inter- national Civil Aviation Organization § 34.71 Non-volatile particulate matter (ICAO) Annex 16, Environmental Pro- (nvPM) test procedures.

tection, Volume II, Aircraft Engine For each Class TF, T3, or T8 engine Emissions, Third Edition, July 2008 (in- manufactured after January 1, 2023, corporated by reference, see § 34.4).

that has a rated output greater than [Doc. No. FAA–2012–1333, 77 FR 76853, Dec. 31, 26.7 kN, the test procedures for meas- 2012, as amended by Doc. No. FAA–2018–0119, uring each required nvPM parameter Amdt. 34–6, 83 FR 9170, Mar. 5, 2018; Doc. No.

are as follows: FAA–2023–2434; Amdt. No. 34–7, 89 FR 31088, (a) Measure the emissions of all Apr. 24, 2024] nvPM parameters required in this part, as applicable.

(b) Collect data from at least three engine tests, with each test conducted Federal Aviation Administration, DOT § 34.73 at the reference LTO time/thrust com- must reach and maintain a steady op- binations shown in paragraph (h) of erating condition before any nvPM this section. emission measurement is made; (c) For the engines referenced in (h) The following landing and takeoff paragraph (b) of this section, all emis- (LTO) cycles apply for nvPM emissions sions certification tests may be con- testing and for calculating weighted ducted on one or more engines of the LTO values: same type design.

T ABLE 1 TO P ARAGRAPH (h) (d) Use a test fuel that meets the specifications described in Appendix 4 Class of ICAO Annex 16, Volume II (incor- TF, T3, T8 Mode porated by reference, see § 34.4). The TIM (min) % of rO test fuel must not have any additive Taxi/idle ......................................... 26.0 7 whose purpose is to suppress nvPM Takeoff ........................................... 0.7 100 emissions.

Climbout ........................................ 2.2 85 (e) (1) When conducting test measure- Descent ......................................... NA NA ments in accordance with paragraphs Approach ....................................... 4.0 30 (a) through (c) of this section, use the equipment and procedures specified in (i) An engine complies with an appli- Appendix 1, Appendix 4, Appendix 6, cable limit if the test results show that and Appendix 7 of ICAO Annex 16, Vol- the engine type certificate family’s ume II (incorporated by reference, see characteristic level does not exceed § 34.4), when demonstrating whether an any limit for maximum nvPM , MC engine meets the applicable nvPM nvPM , and nvPM described in num mass limit specified in § 34.25 of this part. § 34.25.

(2) An applicant that seeks to use a (j) All measurements collected dur- procedure or equipment that differs ing engine tests required in paragraph from any specified in this part must re- (b) of this section must be used in the quest FAA approval in writing with calculation of nvPM. Before any cal- supporting justification before the al- culations are made, the FAA must ap- ternative procedure or equipment may prove the exclusion of any measure- be used to demonstrate compliance. ments that the applicant seeks to ex- The FAA will consult with the EPA on clude, including any justification for any such request. The FAA may ap- such exclusions.

prove the requested alternative for (k) The system and procedure for measuring nvPM, including testing and sampling and measurement of gaseous sampling methods, analytical tech- emissions shall be as specified by Ap- niques, and equipment specifications. pendices 1, 4, 6, and 7 of ICAO Annex 16, Each request must meet one of the fol- Volume II (incorporated by reference, lowing conditions: see § 34.4).

(i) The engine cannot be tested using § 34.73 Demonstration of compliance a specified procedure; or for nvPM emissions.

(ii) The alternative procedure is shown to be equivalent to, or more ac- (a) Each compliance demonstration curate or precise than, the specified by an applicant requires: procedure. (1) Establishing a mean value from (f) Any engine accessory included in tests conducted on one or more en- a type design that may reasonably be gines; expected to influence either nvPM (2) Calculating a ‘‘characteristic emissions or measurements must be in- level’’ by applying a set of statistical stalled on the engine before testing. factors that take into account the The test engine must not extract shaft number of engines tested in accordance power or bleed service air to provide with § 34.71(b) of this part; and power to auxiliary gearbox-mounted (3) Rounding each characteristic components necessary to drive aircraft level to the same number of decimal systems; places as the corresponding emission (g) For each percentage of rated out- limit.

put thrust level prescribed in para- (b) In demonstrating compliance with graph (h) of this section, a test engine this subpart, an applicant must use the 14 CFR Ch. I (1–1–25 Edition) § 34.73 nvPM measurements collected in ac- physically tested, develop a single, sep- cordance with § 34.71 as follows: arate curve fit; (1) An engine complies with an appli- (B) Determine the maximum nvPM MC cable standard when the engine type from each engine curve fit resulting certificate family’s characteristic level from paragraph (c)(1) of this section; does not exceed any nvPM limit de- and scribed in § 34.25 of this part; and (C) If more than one engine is phys- (2) A compliance demonstration con- ically tested, average the nvPM val- MC sists of: ues from paragraph (c)(2) of this sec- (i) Determining the maximum tion to determine the overall max- nvPM , and the mean value for imum nvPM value for the model MC MC nvPM and nvPM from the data tested; or mass num collected in accordance with paragraph (iii) Method 3— § 34.71(f) of this part; (A) Develop a curve fit of nvPM MC (ii) Correcting each data point to versus thrust for each test conducted standard temperature and pressure on each engine physically tested; conditions; (B) From each curve fit developed in (iii) Applying the appropriate statis- paragraph (c)(1) of this section, use the tical factor shown in Table 6–1 of Ap- resultant curve fit equation to solve pendix 6 of ICAO Annex 16, Volume II for each maximum; (incorporated by reference, see § 34.4) to (C) Average the maximum values for account for the number of engines test- each engine physically tested; and ed; and (D) Average the maximum values de- (iv) Rounding each characteristic termined in paragraph (c)(1)(iii)(C) of level to the same number of decimal this section to determine the overall places as the corresponding nvPM limit average maximum nvPM value.

MC in § 34.25 of this part. (2) Using the data measured in (c) (1) In determining maximum § 34.71(b) of this part, determine the nvPM , an applicant must use one of nvPM characteristic levels for nvPM MC num the following evaluation methods for and nvPM as follows: mass all engines measured in accordance (i) Average all nvPM and nvPM num mass with § 34.71(c) of this par and using the measurements in units of number of thrust settings given in § 34.71(h) of this particles per kN or mg per kN, as appli- part. An applicant may choose to cable, from each emissions test at each measure additional thrust settings; percentage of rated output thrust set- while there is no restriction on the ting; number of thrust settings measured, (ii) Multiply the averaged measure- the same thrust settings must be used ment from paragraph (a)(2)(i) of this on each engine tested. A dataset con- section by the appropriate time in sists of nvPM measurements made at mode (TIM) as shown in § 34.71(h); MC each thrust setting across the thrust (iii) Sum the products from para- range chosen by the applicant for each graph (a)(2)(ii) of this section to deter- engine. Plot all nvPM measurements mine the LTO values for nvPM and MC num versus thrust setting. nvPM ; and mass (i) Method 1— (iv) Divide the result of paragraph (A) Average the individual data (a)(2)(iii) of this section by the char- points measured at each thrust setting acteristic level factor, shown in Table to develop one dataset of nvPM mass A6–1 of Appendix 6 of ICAO Annex 16, concentration for each engine tested, Volume II (incorporated by reference, creating an average dataset for each see § 34.4), for the number of engines engine; and physically tested to determine the (B) Use the averages generated in nvPM and nvPM characteristic mass num paragraph (c)(1) of this section to de- values.

velop a single curve fit to determine (d) The data used to determine the the overall maximum nvPM value; regressed curves must meet a 90% con- MC (ii) Method 2— fidence interval, CI , limit of ± 1.5% of (A) Measure individual data points of each nvPM limit specified in § 34.25 of nvPM versus thrust. Using all this part. If a certification test fails to MC datasets generated for each engine meet the CI limit, the engine type Federal Aviation Administration, DOT Pt. 35 may still comply with the require- (iv) nvPM EI (particles/kg of fuel) num ments. Failure may be caused by exces- at each thrust setting of the LTO sive data scatter, too few data points, cycle; or erroneous data used to regress an (v) nvPM number emission rate accurate curve. Without deleting or re- [nvPM EI × fuel flow] in particles/s; num (vi) Total gross emissions of nvPM moving any prior measurement data, mass measured over the LTO cycle in additional data acquired from further mg; tests may improve the CI by adding to the sample population. (vii) Total gross emissions of nvPM number measured over the LTO cycle (e) The following information must in particles; be reported to the FAA substantiating (viii) LTO nvPM /thrust in mg/kN; compliance with nvPM limits of § 34.25 mass (ix) LTO nvPM /thrust in particles/ of this part: num kN; and (1) The values of nvPM emissions (x) Maximum nvPM in μ g/m ; and MC measured and computed in accordance (5) For each engine tested for certifi- with the procedures and calculated as cation purposes, the characteristic lev- required by this subpart in § 34.71 of els for the maximum nvPM , the LTO MC this part and paragraphs (a) through nvPM /thrust, and the LTO nvPM / mass num (d) of this section; thrust.

(2) For each engine tested: (i) Engine model, series, and serial PART 35—AIRWORTHINESS number; STANDARDS: PROPELLERS (ii) Rated thrust (kN); (iii) Overall pressure ratio; Subpart A—General (iv) The methods of data acquisition; and Sec.

(v) The method of data analysis cho- 35.1 Applicability.

sen by the applicant under paragraphs 35.2 Propeller configuration.

35.3 Instructions for propeller installation (a) through (d) of this section.

and operation.

(3) Demonstration that the fuel used 35.4 Instructions for Continued Airworthi- for each test is in compliance with the ness.

fuel specification listed in Appendix 4 35.5 Propeller ratings and operating limita- of ICAO Annex 16, Volume II (incor- tions.

porated by reference, see § 34.4). For the 35.7 Features and characteristics.

fuel used for nvPM emissions certifi- Subpart B—Design and Construction cation, include the following fuel char- acteristics: 35.11 [Reserved] (i) Hydrogen/carbon ratio; 35.13 [Reserved] (ii) Net heat of combustion (MJ/kg); 35.15 Safety analysis.

35.16 Propeller critical parts.

(iii) Hydrogen content (mass per 35.17 Materials and manufacturing methods.

cent); 35.19 Durability.

(iv) Total aromatics content (volume 35.21 Variable and reversible pitch propel- per cent); lers.

(v) Naphthalene content (volume per 35.22 Feathering propellers.

cent); and 35.23 Propeller control system.

35.24 Strength.

(vi) Sulfur content (ppm by mass).

(4) For each engine tested for certifi- Subpart C—Tests and Inspections cation purposes, the following values measured and computed in accordance 35.31 [Reserved] with the procedures of § 34.71 of this 35.33 General.

35.34 Inspections, adjustments and repairs.

part: 35.35 Centrifugal load tests.

(i) Fuel flow (kg/s) at each thrust set- 35.36 Bird impact.

ting of the LTO cycle; 35.37 Fatigue limits and evaluation.

(ii) nvPM EI (mg/kg of fuel) at mass 35.38 Lightning strike.

each thrust setting of the LTO cycle; 35.39 Endurance test.

(iii) nvPM mass emission rate [nvPM 35.40 Functional test.

EI × fuel flow] in mg/s; 35.41 Overspeed and overtorque.

mass