§34.71. Non-volatile particulate matter (nvPM) test procedures. — Inbound Citations

(2) Environmental Protection, Volume II—Aircraft Engine Emissions, Fourth Edition, July 2017 (ICAO Annex 16, Volume II), in §§ 34.71 and 34.73.

(b) In demonstrating compliance with this subpart, an applicant must use the nvPM measurements collected in accordance with § 34.71 as follows:

(1) An engine complies with an applicable standard when the engine type certificate family's characteristic level does not exceed any nvPM limit described in § 34.25 of this part; and

(i) Determining the maximum nvPMMC, and the mean value for nvPMmass and nvPMnum from the data collected in accordance with paragraph § 34.71(f) of this part;

(ii) Correcting each data point to standard temperature and pressure conditions;

(iii) Applying the appropriate statistical factor shown in Table 6-1 of Appendix 6 of ICAO Annex 16, Volume II (incorporated by reference, see § 34.4) to account for the number of engines tested; and

(iv) Rounding each characteristic level to the same number of decimal places as the corresponding nvPM limit in § 34.25 of this part.

(1) When conducting test measurements in accordance with paragraphs (a) through (c) of this section, use the equipment and procedures specified in Appendix 1, Appendix 4, Appendix 6, and Appendix 7 of ICAO Annex 16, Volume II (incorporated by reference, see § 34.4), when demonstrating whether an engine meets the applicable nvPM limit specified in § 34.25 of this part.

(1) When conducting test measurements in accordance with paragraphs (a) through (c) of this section, use the equipment and procedures specified in Appendix 1, Appendix 4, Appendix 6, and Appendix 7 of ICAO Annex 16, Volume II (incorporated by reference, see § 34.4), when demonstrating whether an engine meets the applicable nvPM limit specified in § 34.25 of this part.

(2) Calculating a “characteristic level” by applying a set of statistical factors that take into account the number of engines tested in accordance with § 34.71(b) of this part; and

(1) When conducting test measurements in accordance with paragraphs (a) through (c) of this section, use the equipment and procedures specified in Appendix 1, Appendix 4, Appendix 6, and Appendix 7 of ICAO Annex 16, Volume II (incorporated by reference, see § 34.4), when demonstrating whether an engine meets the applicable nvPM limit specified in § 34.25 of this part.

(1) In determining maximum nvPMMC, an applicant must use one of the following evaluation methods for all engines measured in accordance with § 34.71(c) of this par and using the thrust settings given in § 34.71(h) of this part. An applicant may choose to measure additional thrust settings; while there is no restriction on the number of thrust settings measured, the same thrust settings must be used on each engine tested. A dataset consists of nvPMMC measurements made at each thrust setting across the thrust range chosen by the applicant for each engine. Plot all nvPMMC measurements versus thrust setting.

(A) Average the individual data points measured at each thrust setting to develop one dataset of nvPM mass concentration for each engine tested, creating an average dataset for each engine; and

(B) Use the averages generated in paragraph (c)(1) of this section to develop a single curve fit to determine the overall maximum nvPMMC value;

(A) Using all datasets generated for each engine physically tested, develop a single, separate curve fit;

(B) Determine the maximum nvPMMC from each engine curve fit resulting from paragraph (c)(1) of this section; and

(C) If more than one engine is physically tested, average the nvPMMC values from paragraph (c)(2) of this section to determine the overall maximum nvPMMC value for the model tested; or

(A) Develop a curve fit of nvPMMC versus thrust for each test conducted on each engine physically tested;

(B) From each curve fit developed in paragraph (c)(1) of this section, use the resultant curve fit equation to solve for each maximum;

(C) Average the maximum values for each engine physically tested; and

(D) Average the maximum values determined in paragraph (c)(1)(iii)(C) of this section to determine the overall average maximum nvPMMC value.

(i) Determining the maximum nvPMMC, and the mean value for nvPMmass and nvPMnum from the data collected in accordance with paragraph § 34.71(f) of this part;

(1) In determining maximum nvPMMC, an applicant must use one of the following evaluation methods for all engines measured in accordance with § 34.71(c) of this par and using the thrust settings given in § 34.71(h) of this part. An applicant may choose to measure additional thrust settings; while there is no restriction on the number of thrust settings measured, the same thrust settings must be used on each engine tested. A dataset consists of nvPMMC measurements made at each thrust setting across the thrust range chosen by the applicant for each engine. Plot all nvPMMC measurements versus thrust setting.

(A) Average the individual data points measured at each thrust setting to develop one dataset of nvPM mass concentration for each engine tested, creating an average dataset for each engine; and

(B) Use the averages generated in paragraph (c)(1) of this section to develop a single curve fit to determine the overall maximum nvPMMC value;

(A) Using all datasets generated for each engine physically tested, develop a single, separate curve fit;

(B) Determine the maximum nvPMMC from each engine curve fit resulting from paragraph (c)(1) of this section; and

(C) If more than one engine is physically tested, average the nvPMMC values from paragraph (c)(2) of this section to determine the overall maximum nvPMMC value for the model tested; or

(A) Develop a curve fit of nvPMMC versus thrust for each test conducted on each engine physically tested;

(B) From each curve fit developed in paragraph (c)(1) of this section, use the resultant curve fit equation to solve for each maximum;

(C) Average the maximum values for each engine physically tested; and

(D) Average the maximum values determined in paragraph (c)(1)(iii)(C) of this section to determine the overall average maximum nvPMMC value.