Pt. 36, App. H 14 CFR Ch. I (1-1-19 Edition) (i) The beginning of the approach profile is represented by helicopter position E. The position of the helicopter is recorded for a sufficient distance (EK) to ensure recording of the entire interval during which the measured helicopter noise level is within 10 dB of Maximum Tone Corrected Perceived Noise Level (PNLTM). The reference flight path, ErKr represents a stable flight condition in terms of torque, rpm, indicated airspeed, and rate of descent resulting in a 6Section approach angle. (ii) The test approach profile is defined by the approach angle h passing directly over the station A at a height of AH, to position K, which terminates the approach noise certification profile. The test approach angle h must be between 5.5Section and 6.5Section. (2) The helicopter approaches position H along a constant 6Section approach slope throughout the 10 dB down time period. The helicopter crosses position E and proceeds along the approach slope crossing over station A until it reaches position K. Position Description Mr ... Position on reference flyover flight path corresponding to PNLTM of station A. Position on measured approach flight path corresponding to PNLTM at station A. Position on reference approach flight path corresponding to PNLTM at station A. Sideline noise measuring station (note: a subscript denotes the aircraft orientation relative to the direction of flight). N ..... Nr .... S ..... FLIGHT PROFILE DISTANCES Distance Unit Meaning AF ..... Feet AG ..... Feet Takeoff Height. The vertical distance between helicopter and station A. Flyover Height. The vertical distance between the helicopter and station A. Approach Height. The vertical distance between the helicopter and station A. Measured Takeoff Noise Path. The distance from station A to the measured helicopter position L. Reference Takeoff Noise Path. The distance from station A to the reference helicopter position Lr. Measured Flyover Noise Path. The distance from station A to the measured helicopter position M. Reference Flyover Noise Path. The distance from station A to helicopter position Mr on the reference flyover flight path. Measured Approach Noise Path. The distance from station A to the measured helicopter noise position N. Reference Approach Noise Path. The distance from station A to the reference helicopter position Nr. Takeoff Flight Path Distance. The distance from position C at which the helicopter establishes a constant climb angle on the takeoff flight path passing over station A and continuing to position I at which the position of the helicopter need no longer be recorded. Flyover Flight Path Distance. The distance from position D at which the helicopter is established on the flyover flight path passing over station A and continuing to position J at which the position of the helicopter need no longer be recorded. Approach Flight Path Distance. The distance from position E at which the helicopter establishes a constant angle on the approach flight path passing over station A and continuing to position K at which the position of the helicopter need no longer be recorded. AH ..... Feet Section H36.5 Symbols and units. The following symbols and units as used in this appendix for helicopter noise certification have the following meanings. AL ..... Feet ALr .... Feet FLIGHT PROFILE IDENTIFICATION - POSITIONS AM .... Feet AMr ... Feet AN ..... Feet ANr .... Feet CI ...... Feet DJ ..... Feet EK ..... Feet Position Description A ..... Location of the noise measuring point at the flighttrack noise measuring station vertically below the reference (takeoff, flyover, or approach) flight path. Start of noise certification takeoff flight path. Start of noise certification reference takeoff flight path. Start of noise certification flyover flight path. Start of noise certification reference flyover path. Start of noise certification approach flight path. Start of noise certification reference approach flight path. Position on takeoff flight path directly above noise measuring station A. Position on reference takeoff path directly above noise measuring Station A. Position on flyover flight path directly above noise measuring station A. Position on reference flyover path directly above noise measuring Station A. Position on approach flight path directly above noise measuring station A. Position on reference path directly above noise measuring Station A. End of noise type certification takeoff flight path. End of noise type certification reference takeoff flight path. End of noise type certification flyover flight path. End of noise type certification reference flyover flight path. End of noise certification approach type flight path. End of noise type certification reference approach flight path. Position on measured takeoff flight path corresponding to PNLTM at station A. Position on reference takeoff flight path corresponding to PNLTM of station A. Position on measured flyover flight path corresponding to PNLTM of station A. C ..... Cr .... D ..... Dr .... E ..... Er .... F ..... Fr .... G ..... Gr .... H ..... Hr .... I ...... Ir ..... J ...... Jr ..... K ..... Kr .... L ..... spaschal on DSK3GDR082PROD with CFR FLIGHT PROFILE IDENTIFICATION - POSITIONS - Continued Lr .... M .... PART B - NOISE MEASUREMENT UNDER Section H36.101 Noise certification test and measurement conditions. (a) General. This section prescribes the conditions under which aircraft noise certification tests must be conducted and the 818 VerDate Sep<11>2014 12:50 Apr 30, 2019 Jkt 247046 PO 00000 Frm 00828 Fmt 8010 Section 36.801 Sfmt 8002 Y:\SGML\247046.XXX 247046