14CFR vol1 part36 - 80 pages

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(b) Propeller Overhaul Section. (1) Disassembly information ...
PART 36 - NOISE STANDARDS: AIRCRAFT TYPE AND AIRWORTHINESS C...
Subpart A - General
36.1 Applicability and definitions.
36.2 Requirements as of date of application.
36.3 Compatibility with airworthiness requirements.
36.5 Limitation of part.
36.6 Incorporations by reference.
36.7 Acoustical change: Transport category
36.9 Acoustical change: Propeller-driven
36.11 Acoustical change: Helicopters.
36.13 Acoustical change: Tiltrotor aircraft.
Subpart B - Transport Category Large
36.101 Noise measurement and evaluation.
36.103 Noise limits.
36.105 Flight Manual Statement of Chapter
4 equivalency.
36.106 Flight Manual statement of Chapter
14 noise level equivalency.
Subpart C [Reserved]
Subpart D - Noise Limits for Supersonic
...

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Section 36.1
14 CFR Ch. I (1-1-19 Edition)
Subpart O - Documentation, Operating
36.1501 Procedures, noise levels and other
36.1581 Manuals, markings, and placards.
36.1583 Noncomplying agricultural and fire
Section 36.101
106(g), 40113, 44701-44702, 44704, 44715; sec. 305,
18, 1969, unless otherwise noted.
Subpart A - General
Section 36.1 Applicability and definitions.
(a) This part prescribes noise standards for the issue of th...
1, 1966) or for dispersing fire fighting
Section 137.3 of this chapter, as effective on
20, 1976).
(b) Each person who applies under
(c) Each person who applies under
Section 21.93(b) of this chapter must show that
36.13 of this part in addition to the applicable airworthine...
(d) Each person who applies for the
...

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Section 36.1
75,000 pounds and that are powered by
(e) Each person who applies for the
(f) For the purpose of showing compliance with this part for...
11-B (Incorporated by reference, see
Section 36.6).
(g) For the purpose of showing compliance with this part for...
(h) For the purpose of showing compliance with this part, fo...
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Section 36.1
14 CFR Ch. I (1-1-19 Edition)
(i) For the purpose of showing compliance with this part for...
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Section 36.5
6, 1975]
Section 36.2 Requirements as of date of application.
(a) Section 21.17 of this chapter notwithstanding, each pers...
(b) Section 21.101(a) of this chapter
(c) If an applicant elects to comply
36-24, 67 FR 63195, Oct. 10, 2002]
Section 36.3 Compatibility with airworthiness requirements.
1988]
Section 36.5 Limitation of part.
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Section 36.6
14 CFR Ch. I (1-1-19 Edition)
31, 82 FR 46129, Oct. 4, 2017]
Section 36.6
(a) Certain material is incorporated
12 New England Executive Park, Burlington, MA 01801.
30337.
76137.
15000 Aviation Boulevard, Hawthorne,
7th Avenue, #14, Anchorage, AK 99513.
(b) International Civil Aviation Organization (ICAO), Docume...
999 University Street, Montreal, Quebec,
5H7,
Section 36.1(f), and appendices A and B to part
36.
Section 36.1(f) and appendices A and B to part
36.
(c) International Electrotechnical
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Section 36.7
1995 (IEC 61094-3) IBR approved for appendix A to part 36.
61260,
60942,
(d) Society of Automotive Engineers,
15096,
Section 36.7 Acoustical change: Transport
(a) Applicability. This section applies
(b) General requirements. Except as
(c) Stage 1 airplanes. For each Stage 1
(i) There may be no reduction in
(d) Stage 2 airplanes. If an airplane is
(b) of this section:
(i) The airplane, after the change in
3 EPNdB, or (B) each Stage 2 noise
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Section 36.9
14 CFR Ch. I (1-1-19 Edition)
(i) The airplane may not be a Stage 1
(e) Stage 3 airplanes. If an airplane is
(b) of this section:
(i) Be a Stage 2 airplane after the
14, 1989.] The airplane must remain a
(f) Stage 4 airplanes. (1) If an airplane
(g) Stage 5 airplanes. If an airplane is
36-8, 43 FR 8730, Mar. 2, 1978; Amdt. 36-10, 43
33464, June 29, 1981; Amdt. 36-15, 53 FR 16366,
36-17, 54 FR 21042, May 15, 1989; Amdt. 36-54,
67 FR 45212, July 8, 2002; Amdt. 36-26, 70 FR
38749, July 5, 2005; FAA Doc. No. FAA-2015-
3782, Amdt. No. 36-31, 82 FR 46130, Oct. 4,
2017]
Section 36.9 Acoustical change: Propellerdriven small airpla...
(a) If the airplane was type certificated under this part pr...
Section 36.501 of this part.
(b) If the airplane was not type certificated under this par...
50157, Dec. 13, 1988; Amdt. 36-19, 57 FR 41369,
...

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Section 36.101
(a) General requirements. Except as
7,000 pounds that alternatively demonstrate compliance under...
(b) Stage 1 helicopters. Except as provided in Section 36.80...
2 noise levels specified in section
(c) Stage 2 helicopters. For each helicopter that is Stage 2...
(d) Stage 3 helicopters. For a helicopter that is a Stage 3 ...
2004; Amdt. 36-30, 79 FR 12044, Mar. 4, 2014]
Section 36.13 Acoustical
(a) In showing compliance with Appendix K of this part, nois...
(b) Compliance with the noise limits
(c) After a change in type design,
Subpart B - Transport Category
Section 36.101 Noise measurement and evaluation.
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Section 36.103
14 CFR Ch. I (1-1-19 Edition)
Section 36.103 Noise limits.
(a) For subsonic transport category
(b) Type certification applications
(c) Type certification applications
(d) For airplanes with a maximum
(e) For airplanes with a maximum
2005; FAA Doc. No. FAA-2015-3782, Amdt. No.
36-31, 82 FR 46130, Oct. 4, 2017]
Section 36.105 Flight Manual Statement of
2002. - .
41610, July 20, 2005; FAA Doc. No. FAA-2015-
3782, Amdt. No. 36-31, 82 FR 46129, Oct. 4,
2017]
Section 36.106 Flight Manual statement of
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Section 36.501
2015. - 
31, 82 FR 46129, Oct. 4, 2017]
Subpart C [Reserved]
Subpart D - Noise Limits for Supersonic Transport Category A...
Section 36.301 Noise limits: Concorde.
(a) General. For the Concorde airplane, compliance with this...
Subpart B of this part, and demonstrated at the measuring po...
(b) Noise limits. It must be shown, in
2002]
Subpart E [Reserved]
Subpart F - Propeller Driven Small
Section 36.501 Noise limits.
(a) Compliance with this subpart
1973; and propeller-driven, commuter
(i) Except as provided in paragraph
(a)(3)(ii) of this section, for an airplane
(b) For aircraft covered by this subpart for which certifica...
(c) For aircraft covered by this subpart for which certifica...
1987; Amdt. 36-16, 53 FR 47400, Nov. 22, 1988;
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...

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Section 36.801
14 CFR Ch. I (1-1-19 Edition)
Subpart G [Reserved]
Subpart H - Helicopters
1988; 53 FR 7728, Mar. 10, 1988, unless otherwise noted.
Section 36.801 Noise measurement.
2004]
Section 36.803 Noise evaluation and calculation.
Section 36.805 Noise limits.
(a) Compliance with the noise levels
(b) For helicopters covered by this
1986 and before May 5, 2014, that the
(c) For helicopters for which application for issuance of an...
(d) Helicopters in the primary category:
(d)(2) of this section, for a helicopter
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Section 36.1581
(i) Has a normal or transport type
(v) For which application for conversion to the primary cate...
2014]
Subpart K - Tiltrotors
Section 36.1101 Noise measurement and evaluation.
Section 36.1501 Procedures, noise levels and
(a) All procedures, weights, configurations, and other infor...
(b) Where supplemental test data are
Section 36.1103
Subpart O - Documentation, Operating Limitations and Informa...
(a) Compliance with the maximum
(b) To demonstrate compliance with
Section K4, Noise Limits of this part.
Section 36.1581 Manuals, markings, and placards.
(a) If an Airplane Flight Manual or
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Section 36.1583
14 CFR Ch. I (1-1-19 Edition)
(b) If supplemental operational noise
(c) The following statement must be
(d) For transport category large airplanes and jet airplanes...
(e) For propeller driven small airplanes and for propeller-d...
(f) For primary, normal, transport,
(g) Except as provided in paragraphs
(d), (e), and (f) of this section, no operating limitations ...
Section 36.1583 Noncomplying
(a) This section applies to propellerdriven, small airplanes...
1966) or for dispensing fire fighting materials; and
(i) For which application is made for
1980; or
(b) For airplanes covered by this section an operating limit...
1988; Amdt. 36-18, 54 FR 34330, Aug. 18, 1989]
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Section A36.1 Introduction
Section A36.2 Noise Certification Test and
(a) No precipitation;
(b) Ambient air temperature not above 95
(c) Relative humidity and ambient temperature over the whole...
(d) If the atmospheric absorption coefficients vary over the...
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14 CFR Ch. I (1-1-19 Edition)
(e) Average wind velocity 33 ft (10 m) above
(f) No anomalous meteorological or wind
(g) Meteorological measurements must be
Section A36.3 Measurement of Airplane Noise
0Section, the sound is said to be received at the
90Section, the sound is said to be received at  - grazing in...
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20 SectionPa.
(a) Air temperature 73.4 SectionF (23 SectionC);
(b) Static air pressure 101.325 kPa; and
(c) Relative humidity 50%.
(a) A windscreen (See A36.3.4.);
(b) A microphone system (See A36.3.5):
(c) A recording and reproducing system to
(d) A one-third octave band analysis system (see A36.3.7); a...
(e) Calibration systems to maintain the
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14 CFR Ch. I (1-1-19 Edition)
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(a) For aircraft noise signals for which the
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14 CFR Ch. I (1-1-19 Edition)
50 dB minus the change in attenuation introduced by a change...
(a) A set of 24 one-third octave band filters,
(b) Response and averaging properties in
(c) The interval between successive sound
(d) For those analysis systems that do not
(e) The analysis system must operate in
2 seconds(s) after the onset and 0.5 and 1s
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1.25 seconds after the start of the associated
2 second averaging period.
60942 as amended (incorporated by reference,
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14 CFR Ch. I (1-1-19 Edition)
0.2 dB. The correction for frequency response
20 dB below the maximum PNL of the aircraft.
Section A36.4 Calculation of Effective Perceived
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(a) The 24 one-third octave bands of sound
(b) A tone correction factor C(k) is calculated for each spe...
(c) The tone correction factor is added to
(d) A duration correction factor, D, is computed by integrat...
(e) Effective perceived noise level, EPNL,
(a) Step 1: For each one-third octave band
(b) Step 2: Combine the perceived noisiness
(c) Step 3: Convert the total perceived
(a) Step 1: After applying the corrections
(b) Step 2: Encircle the value of the slope,
(c) Step 3:
(d) Step 4: Compute new adjusted sound
(e) Step 5: Recompute new slope s-(i, k), including one for ...
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14 CFR Ch. I (1-1-19 Edition)
(f) Step 6: For i, from 3 through 23, compute the arithmetic...
(g) Step 7: Compute final one-third octaveband sound pressur...
(h) Setp 8: Calculate the differences, F
1.5.
(i) Step 9: For each of the relevant onethird octave bands (...
2.
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(j) Step 10: Designate the largest of the
9, as C(k). (An example of the tone correction
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14 CFR Ch. I (1-1-19 Edition)
(a) No important tones are recorded in two
(b) That if an important tone has occurred,
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(a) Half-Second time intervals for Dt; or
(b) A shorter time interval with approved
(a) The slopes (M(b), M(c), M(d) and M(e))
(b) The intercepts (SPL(b) and SPL(c)) of
(c) The coordinates of the discontinuities,
(a)
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14 CFR Ch. I (1-1-19 Edition)
(b)
(d)
(c)
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Section A36.5 Reporting of Data to the FAA
(a) Air temperature and relative humidity;
(b) Maximum, minimum and average wind
(c) Atmospheric pressure.
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14 CFR Ch. I (1-1-19 Edition)
(a) Type, model and serial numbers (if any)
(b) Gross dimensions of airplane and location of engines;
(c) Airplane gross weight for each test run
(d) Airplane configuration such as flap, airbrakes and landi...
(e) Whether auxiliary power units (APU),
(f) Status of pneumatic engine bleeds and
(g) Indicated airspeed in knots or kilometers per hour for e...
(h) Engine performance data:
(i) Airplane flight path and ground speed
(j) The applicant must report whether the
(a) Computing the arithmetic average for
(b) Computing the overall arithmetic average for each refere...
Section A36.6 Nomenclature: Symbols and Units
0.5 second.
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20 SectionPa
20 SectionPa
20 SectionPa
20 SectionPa
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20 SectionPa
20 SectionPa
Section ..................
20 SectionPa
100m.
100m.
Section A36.7 Sound Attenuation in Air
(i) = 10
0 /1000 + 6.33  10
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1010 ( log H  -  1.97274664 + 2.288074  10  - 2 )
20 SectionPa
14 CFR Ch. I (1-1-19 Edition)

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1010 ( log H  -  1.328924 + 3.179768  10  - 2  )
Section A36.8 [Reserved]
0 /1000 + 1.1394  10
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(i) = 10

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14 CFR Ch. I (1-1-19 Edition)
(a) Attenuation of the noise along its path
(b) Duration of the noise as affected by the
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Section A36.9 Adjustment of Airplane Flight

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(c) Source noise emitted by the engine as
(d) Airplane/engine source noise as affected
(a) When the amount of the adjustment
(b) When the resulting final EPNL value on
(a) The airplane begins the takeoff roll at
(b) Position K1 is the takeoff noise measuring station and A...
(c) The distance AF is the distance over
(a) The airplane begins its noise certification approach fli...
(b) Position K3 is the approach noise measuring station and ...
(c) The distance GI is the distance over
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14 CFR Ch. I (1-1-19 Edition)
(a) The portions of the test flight path and
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(b) The portions of the test flight path and
(i) Form the same angle q with their respective flight paths...
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14 CFR Ch. I (1-1-19 Edition)
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(a) Convert the corrected values, SPL(i)r,
(b) Calculate the correction term D1 using
(a) Add D2 arithmetically to the EPNL calculated from the me...
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14 CFR Ch. I (1-1-19 Edition)
(a) If the symmetrical measurement point
(b) If the condition described in paragraph
(a) of this section is not met, then it is assumed that the ...
(a) The portions of the test flight path and
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10 dB of the peak value are included.
(b) The portions of the test flight path and
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14 CFR Ch. I (1-1-19 Edition)
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(i) Q1K and Qr1Kr form the same angle q1
(b)(2) the time tr1 is later (for Qr1Kr >Q1K)
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14 CFR Ch. I (1-1-19 Edition)
36-24, 67 FR 63195, 63196, Oct. 10, 2002; 68 FR
1512, Jan. 10, 2003; Amdt. 36-26, 70 FR 38749,
Section B36.1 Noise measurement and evaluation
(a) The procedures of Appendix A of this
(b) For Stage 4 airplanes, an acceptable alternative to para...
(c) For Stage 5 airplanes, an acceptable alternative to para...
Section 36.6).
Section B36.2 Noise Evaluation Metric
Section B36.3 Reference Noise Measurement
(a) Lateral full-power reference noise
2002, an applicant may use the measurement
(b) Flyover reference noise measurement
(c) Approach reference noise measurement
984 feet (300 m) beyond the threshold.
Section B36.4 Test noise measurement points.
(a) If the test noise measurement points
(b) The applicant must use a sufficient
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Section B36.5 Maximum Noise Levels
(a) For acoustical changes to Stage 1 airplanes, regardless ...
(b) For any Stage 2 airplane regardless of
75,000 pounds or less.
600,000 pounds), reduce the limit by 2 EPNdB;
(c) For any Stage 3 airplane:
(i) For airplanes with more than 3 engines:
106 EPNdB for maximum weight of 850,000
850,000 pounds or more; for each halving of
882,000 pounds or more; for each halving of
617,300 pounds or more; for each halving of
(d) For any Stage 4 airplane, the flyover,
2002. [Incorporated by reference, see Section 36.6].
(e) For any Stage 5 airplane, the flyover,
Section B36.6 Trade-Offs
36.7(c)(1) and 36.7(d)(1)(ii), if the maximum
(a) The sum of the exceedance(s) may not
(b) Any exceedance at any single point
(c) Any exceedance(s) must be offset by a
Section B36.7 Noise Certification Reference
(a) General conditions:
...

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14 CFR Ch. I (1-1-19 Edition)
(i) For Stage 1 airplanes and for Stage 2
(i) A climb gradient of 4 per cent; or
(c) Approach reference procedure:
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Section B36.8 Noise Certification Test
(a) All test procedures must be approved by
(b) The test procedures and noise measurements must be condu...
(c) Acoustic data must be adjusted to the
(d) If the airplane-s weight during the test
(e) For approach, a steady glide path angle
(f) If equivalent test procedures different
4 EPNdB on approach, the resulting numbers
(g) During takeoff, lateral, and approach
36-24, 67 FR 63196, Oct. 10, 2002; 68 FR 1512,
2005; FAA Doc. No. FAA-2015-3782, Amdt. No.
36-31, 82 FR 46131, Oct. 4, 2017]]
PART A - GENERAL
PART B - NOISE MEASUREMENT
PART C - DATA CORRECTION
PART D - NOISE LIMITS
PART A - GENERAL
Section F36.1 Scope. This appendix prescribes noise level li...
PART B - NOISE MEASUREMENT
(a) The test area must be relatively flat
(b) The tests must be carried out under the
...

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14 CFR Ch. I (1-1-19 Edition)
n.m. of an airport anemometer, the airport
(a) A microphone system with frequency
(b) Tripods or similar microphone mountings that minimize in...
(c) Recording and reproducing equipment
(d) Acoustic calibrators using sine wave or
(a) The noise produced by the airplane
(b) The characteristics of the system must
(c) The response of the complete system to
45 to 11,200 Hz.
(d) If limitations of the dynamic range of
(e) If requested by the Administrator, the
(f) The equipment must be acoustically
(g) A windscreen must be employed with
(a) The microphones must be oriented in a
(b) Immediately prior to and after each
(c) The ambient noise, including both
(a) Data representing physical measurements or corrections t...
(b) Measured and corrected sound pressure
(c) The type of equipment used for measurement and analysis ...
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...

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(d) The following atmospheric data, measured immediately bef...
(e) Comments on local topography, ground
(f) The following airplane information
(g) Aircraft speed and position and engine
(a) Tests to demonstrate compliance with
(b) Each test over flight must be conducted:
PART C - DATA CORRECTION
(a) Noise data obtained when the temperature is outside the ...
40 percent, must be corrected to 77 degrees F.
(b) The performance correction prescribed
(c) The performance correction must be
(d) When takeoff distance to 50- is not listed as approved p...
1600- for multi-engine airplanes must be used.
(a) The test results must produce an average dB(A) and its 9...
PART D - NOISE LIMITS
(a) Compliance with this section must be
(b) For airplanes for which application for
10, 1973, the noise level must not exceed 68
1,320 pounds (600 kg.). For weights greater
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...

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14 CFR Ch. I (1-1-19 Edition)
(c) For airplanes for which application for
(b) of this section, except that 80 dB(A) may
(d) For airplanes for which application is
6347, Feb. 11, 1975, as amended by Amdt. 36-
6, 41 FR 56064, Dec. 23, 1976; Amdt. 36-6, 42 FR
4113, Jan. 24, 1977; Amdt. 36-9, 43 FR 8754,
1987; Amdt. 36-16, 53 FR 47400, Nov. 22, 1988;
31, 82 FR 46131, Oct. 4, 2017]
PART A - GENERAL
PART B - NOISE MEASUREMENT
PART C - DATA CORRECTIONS
PART D - NOISE LIMITS
PART A - GENERAL
Section G36.1 Scope. This appendix prescribes limiting noise...
PART B - NOISE MEASUREMENT
(a) The test area must be relatively flat
(b) The tests must be carried out under the
(c) The flight test procedures, measuring
(d) Sound pressure level data for noise
...

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(d) Acoustic calibrators using sine wave or
(a) The noise produced by the airplane
(b) The characteristics of the complete system must comply w...
(c) The response of the complete system to
(d) If equipment dynamic range limitations
11,200 Hz does not vary more than 20 dB between the maximum ...
(e) The output noise signal must be read
651. A graphic recorder, sound level meter, or
(f) The equipment must be acoustically
(g) A windscreen must be employed with
(a) The microphone must be a pressure
2.5 mm thick. The plate shall be placed horizontally and flu...
(b) Immediately prior to and after each
(c) The ambient noise, including both
(a) Data representing physical measurements and adjustments ...
(b) Measured and corrected sound pressure
(c) The type of equipment used for measurement and analysis ...
(d) The following atmospheric data, measured immediately bef...
(e) Comments on local topography, ground
(f) The aircraft position relative to the
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...

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14 CFR Ch. I (1-1-19 Edition)
(g) The following airplane information
(a) The noise measurement point is on the
(b) The takeoff reference flight path must
(c) The takeoff reference flight path must
(i) Takeoff power must be used from the
(i) The beginning of the second segment
PART C - DATA CORRECTIONS
(a) These corrections account for the effects of:
(b) Atmospheric absorption correction is
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(c) No corrections for helical tip Mach
(d) When the test conditions are outside
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14 CFR Ch. I (1-1-19 Edition)
PART D - NOISE LIMITS
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(a) The measuring point must be overflown
(b) The samples must be large enough to
(a) Compliance with this section must be
(b) For single-engine airplanes for which
(c) For single-engine airplanes for which

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1423, and 1431(b)); sec. 6(c), Department of
1970 and 14 CFR 11.45).
50157, Dec. 13, 1988, as amended by Amdt. 36-
22, 64 FR 55602, Oct. 13, 1999; Amdt. 36-54, 67
45504, Aug. 5, 2005; Amdt. 36-28, 71 FR 532,
PART A - REFERENCE CONDITIONS
PART B - NOISE MEASUREMENT UNDER
Section 36.801
PART C - NOISE EVALUATION AND CALCULATION
PART D - NOISE LIMITS UNDER
Section 36.805
PART A - REFERENCE CONDITIONS
Section H36.1 General. This appendix prescribes noise requir...
(a) The conditions under which helicopter
(b) The procedures which must be used
(c) The noise limits for which compliance
Section H36.3 Reference Test Conditions.
(a) Meteorological conditions. Aircraft position, performanc...
(b) Reference test site. The reference test
(c) Takeoff reference profile. (1) Figure H1 illustrates a t...
(d) Level flyover reference profile. The beginning of the le...
...

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14 CFR Ch. I (1-1-19 Edition)
(i) The beginning of the approach profile is
Section H36.5 Symbols and units. The following symbols and u...
PART B - NOISE MEASUREMENT UNDER
Section H36.101 Noise certification test and
(a) General. This section prescribes the conditions under wh...
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Section 36.801

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(b) Test site requirements. (1) Tests to show
(i) For any flight-track or sideline noise
(i) At least one takeoff test and one flyover
6.0 degree Section0.5 degree approach angle and
(i) At least one approach test must be conducted at a weight...
(c) Weather restrictions. The tests must be
20 percent and 95 percent, inclusively.
(d) Aircraft testing procedures. (1) The aircraft testing pr...
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14 CFR Ch. I (1-1-19 Edition)
Section H36.103 Takeoff test conditions.
(a) This section, in addition to the applicable requirements...
(b) A test series must consist of at least six
Section H36.105 Flyover test conditions.
(a) This section, in addition to the applicable requirements...
(b) A test series consists of at least six
(c) Each flyover noise test must be conducted - 
(d) The airspeed shall not vary from the
Section H36.107 Approach test conditions.
(a) This section, in addition to the requirements of section...
(b) A test series must consist of at least six
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(c) The airspeed shall not vary from the
Section H36.109 Measurement of Helicopter
Section H36.111 Reporting and correcting
(a) General. Data representing physical
(b) Data reporting. (1) Measured and corrected sound pressur...
(i) Type, model, and serial numbers, if any,
(v) Airspeed in knots.
(c) Data corrections. (1) Aircraft position,
(i) The helicopter not passing vertically
(d) Validity of results. (1) The test results
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14 CFR Ch. I (1-1-19 Edition)
Section H36.113 Atmospheric attenuation of
(a) The values of the one-third octave band
(b) Attenuation rates. The procedure for determining the atm...
(c) Correction for atmospheric attenuation. (1)
(i) The ambient atmospheric conditions of
PART C - NOISE EVALUATION AND CALCULATION
Section H36.201 Noise Evaluation in EPNdB.
(a) Effective Perceived Noise Level
(b) Notwithstanding the provisions of section A36.4.3.1(a), ...
Section H36.203 Calculation of noise levels.
(a) To demonstrate compliance with the
(b) The calculated noise level for each
90 percent confidence limit for all valid test
Section H36.205 Detailed data correction
(a) General. If the test conditions do not
(i) Atmospheric absorption of sound under
(i) The flight profiles must be determined
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(b) Takeoff profiles. (1) Figure H1 illustrates
(i) The reference takeoff flight path is described in sectio...
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14 CFR Ch. I (1-1-19 Edition)
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(c) Level flyover profiles. (1) The noise type
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14 CFR Ch. I (1-1-19 Edition)
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(d) Approach profiles. (1) Figure H3 illustrates a typical a...
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14 CFR Ch. I (1-1-19 Edition)
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(e) Correction of noise at source during level
(f) PNLT corrections. If the measured ambient atmospheric co...
(i) Step 1. A set of corrected values are
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14 CFR Ch. I (1-1-19 Edition)
(g) Duration corrections. (1) If the measured
(i) Takeoff flight path. For the takeoff path
PART D - NOISE LIMITS UNDER
Section 36.805
Section H36.301 Noise measurement, evaluation,
Section H36.303 [Reserved]
Section H36.305 Noise levels.
(a) Limits. For compliance with this appendix, the applicant...
(i) For takeoff, flyover, and approach calculated noise leve...
(i) For takeoff calculated noise levels - 109
176,370 pounds (80,000 kg) or more, reduced by
3.01 EPNdB per halving of the weight down
(i) For takeoff - For a helicopter having a
176,370 pounds (80,000 kg) or more, the noise
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176,370 pounds (80,000 kg) or more, the noise
176,370 pounds (80,000 kg) or more, the noise
(b) Tradeoffs. Except to the extent limited
4099, Feb. 11, 1988; 53 FR 7728, Mar. 10, 1988, as
2002; Amdt. 36-25, 69 FR 31234, June 2, 2004;
36-30, 79 FR 12045, Mar. 4, 2014; FAA Doc. No.
PART C - NOISE EVALUATION AND CALCULATION
PART D - NOISE LIMITS PROCEDURE UNDER
Section 36.805
PART A - REFERENCE CONDITIONS
Section J36.1 General.
(a) The conditions under which an alternative noise certific...
(b) The alternative procedures which must
(c) The noise limits for which compliance
Section J36.3 Reference Test Conditions.
PART A - REFERENCE CONDITIONS
PART B - NOISE MEASUREMENT PROCEDURE
(a) Meteorological conditions. The following
(b) Reference test site. The reference test
(c) Level flyover reference profile. The reference flyover p...
12:50 Apr 30, 2019
...

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14 CFR Ch. I (1-1-19 Edition)
0.9VH; 0.9VNE; 0.45VH + 65 kts (120 km/h); or
0.45VNE + 65 kts (120 km/h), whichever of the
10 dB-down time interval.
(d) The weight of the helicopter shall be
Section J36.5 [Reserved]
PART B - NOISE MEASUREMENT PROCEDURE
Section J36.101 Noise certification test and
(a) General. This section prescribes the conditions under wh...
(b) Test site requirements. (1) The noise
(c) Weather restrictions. The test must be
10 dB per 100 meters (30.5 dB per 1000 ft) in
(d) Helicopter testing procedures. (1) The helicopter testin...
Section J36.103 [Reserved]
Section J36.105 Flyover test conditions.
(a) This section prescribes the flight test
(b) A test series must consist of at least six
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(a) General. (1) The helicopter noise measured under this ap...
(b)(2) of this section can also be expressed as:
0 .1 LA ( t )
(c) Measurement system. The acoustical
12:50 Apr 30, 2019
Section J36.107 [Reserved]
Section J36.109 Measurement of helicopter noise
(e) and (f) of this section prescribe the calibration and me...
(b) Noise unit definition. (1) The value of
(c) Each flyover noise test must be conducted:
(i) Advancing blade tip Mach number (MAT)
(d) The helicopter test weight for each flyover test must be...
(e) The requirements of paragraph (b)(2) of
...

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14 CFR Ch. I (1-1-19 Edition)
(d) Sensing, recording, and reproducing
(i) The SEL values from each flyover test
(v) A windscreen must be used with the
(e) Calibrations. (1) If the helicopter acoustic signal is t...
(i) The overall sensitivity of the measuring
(f) Noise measurement procedures. (1) The
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Section J36.111 Reporting Requirements.
(a) General. Data representing physical
(b) Data reporting. After the completion of
(i) Type, model, and serial numbers, if any,
(v) Aircraft configuration, including landing gear positions...
(x) Helicopter engine performance as determined from aircraf...
Section J36.113 [Reserved]
PART C - NOISE EVALUATION AND
Section J36.201 Noise Evaluation in SEL.
Section J36.203 Calculation of Noise Levels.
(a) To demonstrate compliance with the
(b) The minimum sample size acceptable
(c) All data used and calculations performed under this sect...
Section J36.205 Detailed Data Correction
(a) When certification test conditions
(b) The adjustment for off-reference altitude may be approxi...
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14 CFR Ch. I (1-1-19 Edition)
(c) The adjustment for the difference between reference airs...
(d) No correction for source noise during
(e) No correction for the difference between the reference g...
(f) No correction for off-reference atmospheric attenuation ...
(g) The SEL adjustments must be less than
2.0 dB(A) for differences between test and reference flight ...
(h) All data used and calculations performed under this sect...
PART D - NOISE LIMITS PROCEDURE UNDER
Section 36.805
Section J36.301 Noise Measurement, Evaluation,
Section J36.303 [Reserved]
Section J36.305 Noise Limits.
(a) For primary, normal, transport, and restricted category ...
3.0
3.0
(b) The procedures required in this amendment shall be done ...
1992; 69 FR 18803, Apr. 9, 2004; Amdt. 36-25, 69
12045, Mar. 4, 2014; FAA Doc. No. FAA-2015-
3782, Amdt. No. 36-31, 82 FR 46131, Oct. 4,
2017]
...

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Section K1 General
Section K2 Noise Evaluation Measure
(b) Flyover reference noise
(a) Takeoff reference noise measurement
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Section K3 Noise Measurement Reference Points

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14 CFR Ch. I (1-1-19 Edition)
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(c) Approach reference noise measurement

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Section K4 Noise Limits
(c) At the approach flight path reference
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(a) At the takeoff flight path reference point:
(b) At the Flyover path reference point: For a

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14 CFR Ch. I (1-1-19 Edition)
Section K5 Trade-Offs
(a) The sum of excesses must not be greater than 4 EPNdB;
(b) The excess at any single point must not
(c) Any excess must be offset by the remaining noise margin ...
(a)-(b) [Reserved]
(c) The takeoff, flyover and approach reference procedures m...
12:50 Apr 30, 2019
Section K6 Noise Certification Reference
(d) If the design characteristics of the
(e) The following reference atmospheric
(f) For tests conducted in accordance with

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(a) A constant takeoff configuration must
(b) The tiltrotor power must be stabilized
(c) The nacelle angle and the corresponding best rate of cli...
(d) The rotor speed must be stabilized at
(e) The weight (mass) of the tiltrotors
(f) The reference takeoff flight profile is a
(a) The tiltrotor must be stabilized for
(b) A constant flyover configuration selected by the applica...
(c) The weight (mass) of the tiltrotor must
(d) In the VTOL/Conversion mode:
(a) The tiltrotor must be stabilized to follow a 6.0 degree ...
(b) An approved airworthiness configuration in which maximum...
(c) The rotor speed must be stabilized at
(d) The constant approach configuration
(e) The weight (mass) of the tiltrotor at
Section K7 Test Procedures
(a) For takeoff: 4.0 EPNdB, of which the
(b) For flyover or approach: 2.0 EPNdB.
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14 CFR Ch. I (1-1-19 Edition)
90 percent and not more than 105 percent of
PART 39 - AIRWORTHINESS
39.1 Purpose of this regulation.
39.3 Definition of airworthiness directives.
39.5 When does FAA issue airworthiness directives?
39.7 What is the legal effect of failing to
39.9 What if I operate an aircraft or use a
39.11 What actions do airworthiness directives require?
39.13 Are airworthiness directives part of
39.15 Does an airworthiness directive apply
39.17 What must I do if a change in a product affects my abi...
39.19 May I address the unsafe condition in
39.21 Where can I get information about
39.23 May I fly my aircraft to a repair facility to do the w...
39.25 How do I get a special flight permit?
39.27 What do I do if the airworthiness directive conflicts ...
48003, July 22, 2002, unless otherwise noted.
Section 39.1
Section 39.3 Definition of airworthiness directives.
Section 39.5 When does FAA issue airworthiness directives?
...