AC 93-2

Advisory circular · Noise Levels for Aircraft used for Commercial Operations in Grand Canyon National Park Special Flight Rules Area

Approved
June 13, 2006
Last reviewed
January 29, 2009
Family
AC 93-2 · 1 version
14 CFR parts
93

Guidance, not mandatory unless a rule or AD requires it. DRS record last changed January 29, 2009.

U.S. Department of Transportation Advisory Circular Federal Aviation Administration Subject:

NOISE LEVELS FOR AIRCRAFT USED

FOR COMMERCIAL OPERATIONS IN

GRAND CANYON NATIONAL PARK

SPECIAL FLIGHT RULES AREA Date: 6/13/2006 Initiated by: AEE-100 AC No: AC-93-2 Change:

1. Purpose. This circular contains the measured or estimated noise levels for aircraft currently used for commercial sightseeing operations in the Grand Canyon National Park (GCNP) special flight rules area, ranked in alphabetical order for the conditions and assumptions described below. This information is provided both for aircraft that have been noise type certificated under 14 CFR part 36, and for aircraft for which no such requirements existed at the time of type certification. The noise level data presented in the appendices are provided for determining the GCNP quiet aircraft technology designation status for each aircraft subject to 14 CFR part 93.

2. Cancellation.

3. Background. On March 29, 2005, the Federal Aviation Administration (FAA) published a Final Rule entitled “Noise Limitations for Aircraft Operations in the Vicinity of Grand Canyon National Park”. This amendment of 14 CFR part 93 is necessary to establish reasonably achievable requirements for aircraft operating in the GCNP to be considered as employing quiet aircraft technology. The standards for the GCNP quiet aircraft technology proposed in the rule will be used to assist the National Park Service (NPS) achieve its statutory mandate to provide for the substantial restoration of natural quiet and to enhance visitor’ experience in the GCNP.

4. Aircraft Noise Limits for GCNP Quiet Aircraft Technology. Noise levels of propeller-driven small airplanes and helicopters that operate at GCNP at the time of preparation of this circular are presented in Appendices 1 and 2. The data were obtained by the methodology described in Section 5 of this circular. The sources of the data as they relate to Section 5 of this circular are designated in the “NOTES” column. The GCNP quiet aircraft technology status of each aircraft is provided in the “QUIET TECHNOLOGY” column.

Appendix 1 provides noise levels of propeller driven small airplanes that are subject to Appendix F or G of 14 CFR part 36. Appendix 1 includes maximum takeoff weights, landing weights, engine type, horsepower, propeller type and diameter.

AC-93-2 6/13/2006 Appendix 2 contains noise levels of helicopters that are subject to Appendix H or J of 14 CFR part 36. This appendix includes maximum takeoff weights, landing weights, engine type, rotor type and diameter.

Aircraft are listed in alphabetical order by make and model in Appendices 1 and 2. The noise levels in the appendices were obtained during the noise certification process as prescribed under 14 CFR part

36. Where no certificated noise level is available, the Administrator may approve an alternative measurement or estimation procedure.

Part 93 classifies aircraft used in commercial sightseeing flight operations over GCNP by the noise they produce. Part 93 establishes the GCNP quiet aircraft technology designation status for propellerdriven small airplanes and helicopters. The status of each aircraft was determined according to its noise nuisance at a common noise sensitive reference point in GCNP. The aircraft noise limits, based on aircraft certification noise levels are shown in Figure 1 through 4 for GCNP quiet aircraft technology.

The noise limits are expressed for propeller-driven small airplanes and helicopters as follows:

(a) For helicopters with a flyover noise level obtained in accordance with the measurement procedures prescribed in Appendix H of part 36, the limit is 80 dB for helicopters having 2 or fewer passenger seats, increasing at 3 decibels per doubling of the number of passenger seats for helicopters having 3 or more passenger seats. The limit for helicopters having 3 or more seats can be calculated using the formula:

EPNL(H) = 80 +10log(# PAX seats/2) dB

(b) For helicopters with a flyover noise level obtained in accordance with the measurement procedures prescribed in Appendix J of part 36, the limit is 77 dB for helicopters having 2 or fewer passenger seats, increasing at 3 decibels per doubling of the number of passenger seats for helicopters having 3 or more passenger seats. The limit for helicopters having 3 or more seats can be calculated using the formula:

SEL(J) = 77 +10log(# PAX seats/2) dB

(c) For propeller-driven airplanes with a measured flyover noise level obtained in accordance with the measurement procedures prescribed in Appendix F of part 36 without the performance correction defined in Sec. F35.201(c), the limit is 69 dB for airplanes having 2 or fewer passenger seats, increasing at 3 decibels per doubling of the number of passenger seats for airplanes having 3 or more passenger seats. The noise limit for propeller-driven airplanes having 3 or more seats can be calculated using the formula:

LAmax(F) = 69 +10log(# PAX seats/2) dB

(d) In the event that a flyover noise level is not available in accordance with Appendix F of 14 CFR part 36, the noise limit for propeller-driven airplanes with a takeoff noise level obtained in accordance with the measurement procedures prescribed in Appendix G is 74 dB or 77 dB depending on 14 CFR part 36 amendment level, for airplanes having two or fewer passenger seats, increasing at 3 dB per doubling of the number of passenger seats for airplanes having three or more passenger seats.

The noise limit for propeller driven airplanes having 3 or more seats can be calculated using the formula:

6/13/06 AC-93-2 LAmax(G) = 74 +10log(# PAX seats/2) dB for aircraft certificated to 14 CFR part 36 Amendment 21 or earlier;

LAmax(G) = 77+10log(# PAX seats/2) dB for aircraft certificated to 14 CFR part 36 Amendment 22 or later.

5. Methodology to Categorize Noise Efficiency. The GCNP noise incentive plan is based on certificated noise levels determined under 14 CFR part 36. These levels may be found in FAA AC 36- 1H or in the aircraft flight manual. Some aircraft, depending on the date of type certification, were not subject to the noise certification provisions of 14 CFR part 36, and do not have noise certification levels. For those aircraft, either measured noise levels from tests that are not approved by the FAA as certification quality (e.g., research test data) or estimates by approved methods were used. All estimated noise certification levels provided in this circular are for the sole and specific purpose of determining compliance with GCNP noise efficiency criteria and may not be used to establish compliance under any regulation.

The following hierarchy of noise level data sources was used in establishing noise levels for aircraft listed in Appendices 1 and 2. The same hierarchy will be used for future additions to the appendices.

1. U.S. type certifications using 14 CFR part 36 with noise certification levels obtained from FAA-approved flight manuals or FAA AC 36-1.

a) For propeller driven small airplanes the hierarchy of regulations is:

1) 14 CFR part 36 Appendix F

2) 14 CFR part 36 Appendix G

b) For helicopters the hierarchy of regulations is:

3) 14 CFR part 36 Appendix J

4) 14 CFR part 36 Appendix H

2. Foreign type certifications using ICAO Annex 16, Volume I with noise certification levels obtained from approved flight manuals, data approved by the foreign civil aviation authority, or FAA AC 36-1.

a) For propeller driven small airplanes the applicable hierarchy of regulations is:

1) ICAO Annex 16, Volume I Chapter 6

2) ICAO Annex 16, Volume I Chapter 10

b) For helicopters the hierarchy of regulations is:

3) ICAO Annex 16, Volume I Chapter 11

4) ICAO Annex 16, Volume I Chapter 8

3. Research or other measurement test data obtained under controlled conditions, documented and corrected to the certification conditions of part 36 Appendix F for small propeller driven airplanes and part 36 Appendix J for helicopters. Preference would be placed on those data obtained under certification-like conditions or those data collected under an FAA-sponsored noise research test.

4. FAA approved noise estimation methods that seek to estimate part 36 Appendix F noise levels for small propeller driven airplanes or part 36 Appendix J noise levels for helicopters.

Currently the following methods may be suitable for use, but are subject to FAA approval on a case-by-case basis.

AC-93-2 6/13/2006

a) For propeller driven small airplanes: Method in Section 2.2 of DOT/FAA/AEE-82- 11

b) For helicopters: SAE/AIR 1989 2

5. FAA approved noise level estimation method using FAA's Integrated Noise Model (INM) or an FAA-approved equivalent.

As one moves down in the hierarchy, the expected level of substantiation (as the representative noise certification level-estimated) by the operator or owner increases, and the level of FAA scrutiny will increase.

The resulting noise levels will vary depending upon the availability of FAA-approved data and its rank in the hierarchy. In the case of helicopters, the noise levels must be the flyover noise certification level and expressed in the noise metric of Effective Perceived Noise Level (14 CFR part 36, Appendix H) or Sound Exposure Level (14 CFR part 36, Appendix J). In the case of small propeller-driven airplanes the noise levels must be the flyover (14 CFR part 36, Appendix F) or takeoff (14 CFR part 36, Appendix G) noise certification level and expressed in the noise metric of maximum A-weighted sound level.

6. Distribution.

7. Revisions.

Carl E. Burleson Director of Environment and Energy

1 DOT/FAA/AEE-82-1: “A Description of Methodologies Used in Estimation of A-Weighted Sound Levels for FAA Advisory Circular AC-36-3B”, published by AEE in January 1982 2 SAE/AIR 1989: “Helicopter External Noise Estimation “, published by Society of Automotive Engineering in December 1992.

6/13/06 AC-93-2

LIST OF FIGURES

AC-93-2 6/13/2006 Figure 1 GCNP Aircaft Noise Limits for Quiet Technology Helicopters Measured Under Appendix H 75 80 85 90 95 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Number of Pasenger Seats Effective Perceived Noise Level (EPNdB) EPNL(H) = 80 +10log(# PAX seats/2) dB

6/13/06 AC-93-2 Figure 2 GCNP Aircaft Noise Limits for Quiet Technology Helicopters Measured Under Appendix J 75 80 85 90 95 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Number of Pasenger Seats Sound Exposure Level (dB) SEL(J) = 77 +10log(# PAX seats/2) dB

AC-93-2 6/13/2006 Figure 3 GCNP Aircaft Noise Limits for Quiet Technology Propeller-Driven Small Airplanes Measured Under Appendix F 65 70 75 80 85 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Number of Pasenger Seats A-Weighted Sound Pressure Level (dBA) Lamax(F) = 69 +10log(# PAX seats/2) dB

6/13/06 AC-93-2 Figure 4 GCNP Aircaft Noise Limits for Quiet Technology Propeller-Driven Small Airplanes Measured Under Appendix G 70 75 80 85 90 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Number of Pasenger Seats A-Weighted Sound Pressure Level (dBA) Lamax(G) = 74 +10log(# PAX seats/2) dB for certifications obtained under 14 CFR part 36 Amendment 21 or earlier Lamax(G) = 77 +10log(# PAX seats/2) dB for certifications obtained under 14 CFR part 36 Amendment 22 or later

AC-93-2 6/13/2006

APPENDICES

APPENDIX I

GCNP INCENTIVE PLAN NOISE LEVELS

PROPELLER-DRIVEN SMALL AIRPLANES Updated 12/22/2008 NOISE LEVEL MAKE MODEL MTOW MLW # OF ENGINES MAKE MODEL ENG.

PWR RPM

EXHAUST # OF PROP BLADES MAKE MODEL PROP DIA RPM PITCH APP. F (dBA) APP. G (dBA) # OF PAX NOTES BEECH 36, A36

3.6

3.6 1 TCM I0-520-B(A) 285 2700 5 3

MCCAULEY 3A32C76 80 2700 V

78.8 5 F NO BEECH 36, A36

3.6

3.6 1 TCM I0-520-BB 275 2550 5 2

MCCAULEY 2A36C23 84 2550 V

78.0 5 F NO BEECH 36, A36

3.65

3.7 1 TCM IO-550-B 300 2700 5 3

MCCAULEY 3A32C406 80 2700 V

78.2 5 F NO BEECH 65A90

9.3

8.8 2 P&W PT6A-20 500 2200 9 3

HARTZELL HC-B3TN-2B/M 93 2200 V

78.7 8 F NO BEECH 76

3.9

3.9 2 LYC O-360-A1G6D 165 2700 2 2

HARTZELL HC-M2YR-2CEUF 76 2700 V

80.2 5 F NO BEECH 76

3.98

3.98 2 LYC O-360-A1G6D 165 2700 5 2

HARTZELL HC-M2YR-2CLUF 76 2700 V

79.5 5 F NO BEECH C99

11.3

11.3 2 P&W PT6A-36 715 2200 9 3

HARTZELL HC-B3TN-3B/M 93 2200 V

79.3 15 F NO BEECH V35

3.4

3.4 1 TCM I0-520-BA 285 2700 5 3

MCCAULEY 3A32C406 78 2700 V

78.1 4 F NO CESSNA 172M

2.3

2.3 1 LYC 0-320-E2D 150 2700 6 2

MCCAULEY 1C160/CTM/DTM 75 2700 F

74.3 3 F NO CESSNA 172P

2.4

2.4 1 LYC 0-320-D2J 150 2700 6 2

MCCAULEY 1C160/DTM 75 2700 F

74.3 3 F NO

QUIET TECHNOLOGY

APPENDIX I

GCNP INCENTIVE PLAN NOISE LEVELS

PROPELLER-DRIVEN SMALL AIRPLANES Updated 12/22/2008 NOISE LEVEL MAKE MODEL MTOW MLW # OF ENGINES MAKE MODEL ENG.

PWR RPM

EXHAUST # OF PROP BLADES MAKE MODEL PROP DIA RPM PITCH APP. F (dBA) APP. G (dBA) # OF PAX NOTES

QUIET TECHNOLOGY CESSNA 182*

2.55

2.55 1 TCM 0-470-L 230 2600 5 2

HARTZELL HC-82XF-1 82 2600 V

72.0 3 F NO CESSNA 182H*

2.8

2.8 1 TCM 0-470-R 230 2600 5 2

MCCAULEY 2A34C66 82 2600 V

72.0 3 F NO CESSNA 182P

2.95

2.95 1 LYC 0-470-R/S 230 2600 5 2

MCCAULEY 2A34C-201/66 82 2600 V

72.0 3 F NO CESSNA 182R 3.1 1 TCM 0-470-V 230 2600 5 2

MCCAULEY C2A34C204 82 2400 V

72.0 3 F NO CESSNA 182Q

2.95

2.95 1 LYC 0-470-U 230 2400 5 2

MCCAULEY C2A34C204 82 2400 V

72.0 3 F NO CESSNA 206*

3.3

3.3 1 TCM IO-520-A 285 2700 5 2

MCCAULEY D2A34C58 82 2700 V

78.5 5 F NO CESSNA 207*

3.8

3.8 1 TCM IO-520-F 285 2700 5 3

MCCAULEY D3A32C90 80 2700 V

77.8 6 F NO CESSNA 207A*

3.8

3.8 1 TCM IO-520-F 285 2700 5 3

MCCAULEY D3A34C404 80 2700 V

79.0 6 F NO CESSNA 208 (AMPHIB)*

7.6

7.3 1 P&W PT6A-114 600 9 3HARTZELL HC-B3MN-3 100 1900 V

72.8 9 F YES CESSNA 208 (LAND)* 8

7.8 1 P&W PT6A-114 600 9 3HARTZELL HC-B3MN-3 100 1900 V

72.8 9 F YES