HomeMy WebLinkAboutPARADISE AIRPORT NOISE EXPOSURE CONTOURS5150 Sunrise Blvd., Suite D-3 • Fair Oaks, CA 95628 • (916) 961-5822 • Fax: (916)961-6418
3.19 West School Ave., Visalia, CA 93291. • (209) 627.4923 Fax: (209) 627-6284 T `
INTRODUCTION:
Brown-Buntin Associates, Inc. (BBA) has completed an analysis of aircraft/airport operations and
related noise levels for the Paradise Airport. The analysis has. been conducted for the preparation
of future year (2005) Community Noise Equivalent Level (CNEL)' noise exposure maps for the
Paradise Airport operations.
The Federal Aviation Administration's (FAA) Integrated Noise Model (INM) Version 5..01 was used
to prepare CNEL noise exposure maps for the Paradise Airport based upon the FAA noise level data
for single engine and twin engine aircraft,.and airport operational factors as described below.
The INM was developed for the FAA, and represents the federally -sanctioned and preferred'..
method for analyzing aircraft/airport noise exposure. Version 5.01 is the currently -available
version of the INM, incorporating an updated data base of aircraft performance parameters
and noise levels.
Projected data for aircraft activity, aircraft fleet mix and airport configuration used in the noise
modeling process were obtained from the most recent (1988) California Aviation System Plan
(CASP), and discussions with the Paradise Airport officials. The following report summarizes
the data, methods and assumptions used in preparing the CNEL noise exposure maps.
The noise descriptor used by the FAA is the Day -Night Average Level (Ldp). The FAA uses the
Day -Night Average Level to describe land use compatibility with respect to aircraft noise exposures.
The FAA airport noise compatibility criterion for residential land uses is 65 dB Ldp. The California
Department of Transportation.Division of Aeronautics uses the 65 dB CNEL descriptor to describe
residential land use compatibility with respect to aircraft noise exposures. Generally, the predicted
Ld,, and CNEL values agree within 1 dB of one another.
The CNEL descriptor is a method of averaging single'event noise levels over a typical 24-hour day,
applying penalties to noise events occurring during the evening .(7 p.m. to' 10 p.m.) hours, and
nighttime (10 p.m. to 7 a.m.) hours. CNEL is usually defined in terms of annual average'conditions,
so that the CNEL measured on a given day may be either less than or greater than the annual
average.
1. For an explanation of terms used in this report, see Appendix A.
1
AIRPORT OPERATIONS:
Airport operational factors which can significantly affect overall noise levels as described by CNEL
include the aircraft fleet mix, the number of daily operations and the time of day .when aircraft
operations occur. Runway use factors also significantly influence CNEL values. Trip length can
affect aircraft single event noise levels, as an aircraft which is prepared for a long flight may carry
more fuel and passengers than for a short.flight. The INM applies corrections to air carrier aircraft
takeoff profiles to account for these differences, but makes no corrections to general aviation aircraft
takeoff profiles.
Aircraft operational assumptions for Paradise Airport are based upon analyses of airport activity,
provided in the CASP and discussions with the Paradise Airport officials. These assumptions are
described by Tables I and H.
Detailed descriptions of aircraft flight tracks_ were provided by the Paradise Airport staff.- Based
upon these data, BBA prepared generalized flight tracks for use in the noise,modeling process to
describe areas with a concentration of aircraft overflights. Figure 1 shows the flight tracks used for
the noise modeling process.
3
TABLE II l '
AVERAGE DAILY OPERATIONS BY AIRCRAFT TYPE
Paradise Airport
Year>«»>> >><><< .............
Based Aircraft Type
INMAircraft Type
'
1995
•2005 .
Piper Cherokee 235
COMSEP
26.5
31.0
Champ 7FC
Cessna 182
Cessna 172
Cessna 210
Bellanca
Luscamb
_
Beechcraft Muskateer
Navion
;
Cessna 150
Piper Clipper
Cessna 180
Mooney M20 -C
Comanche
Trip -Pacer
Cessna 120
Piper Arrow -
BEECH58P
0.8'
L'o
Detailed descriptions of aircraft flight tracks_ were provided by the Paradise Airport staff.- Based
upon these data, BBA prepared generalized flight tracks for use in the noise,modeling process to
describe areas with a concentration of aircraft overflights. Figure 1 shows the flight tracks used for
the noise modeling process.
3
PREPARATION OF CNEL NOISE EXPOSURE MAPS.:
As discussed earlier in this report, the Integrated Noise Model (INM) Version -5.01. was used to..
prepare CNEL noise exposure maps for the airport, based upon the'aircraft noise level and airport
operational factors described in the previous sections. The INM was developed for the FAA, and
represents. the federally -sanctioned and preferred method for analyzing aircraft/airport noise
exposure. Version 5.01 is the most recent version of the INM, incorporating an updated database
of aircraft performance parameters and noise levels.
The INM calculates aircraft noise exposure by mathematically combining aircraft noise levels and -
airport operational factors at a series of points within a cartesian coordinate system which defines
the location of airport runways and aircraft flight tracks. User inputs to the INM include the
following:
a. Airport altitude and mean temperature
b. Runway configuration
c. Aircraft flight track definition
d. Aircraft stage length
e. Aircraft departure and approach profiles
f. Aircraft traffic volume and fleet mix
g. Flight track utilization by aircraft types
The INM data base includes aircraft performance parameters and noise level data for aircraft classes..
When the user specifies a particular aircraft class from the INM data base, the model automatically
provides the necessary inputs concerning aircraft power settings, speed, departure profile and noise
levels. INM default values were used for all fixed -wing aircraft types:
After the model had been prepared for the aircraft classes described in the preceding section; BBA
created INM input files containing the number of operations by aircraft class,,time of day and flight
track for annual average day aircraft operations for the year 2005. The INM was used with these
operational scenarios to prepare' S5, 60 and 65 dB CNEL contours, which have been plotted on
Figure 2. Total surface areas included in each of these CNEL contours are shown by Table III.
TABLE III
SURFACE AREAS WITHIN CNEL CONTOURS
f
Area, Square Miles
55 dB
60 dB
65 dB
Scenario
TABLE III
SURFACE AREAS WITHIN CNEL CONTOURS
Paradise. Airport
Area, Square Miles
55 dB
60 dB
65 dB
Scenario
2005
0.16
0.06
0.02
`The shapes of the CNEL contours are generated by the INM in response to the directional .
characteristics of aircraft noise, while the size of the contours is -affected by the number of aircraft
operations and the noise emissions of the types of aircraft in the aircraft fleet. Predominant aircraft
arrivals and.departures. are to and from the south. Based upon discussions with the Paradise Airport.
staff, approximately 5 percent of all arrivals are from the north along runway 17, and approximately
1 percent of departures are to the north along runway 35. Therefore, the noise. level* contours. for the
airport are oriented predominantly to the south.
Respectfully submitted,
Brown-Buntin Associates, Inc.
Jim -'Brennan
Senior Consultant .
oil pwfmi
x
.-
APPENDIX A.-
ACOUSTICAL TERMINOLOGY
ACOUSTICAL
AMBIENT
NOISE ' The composite of noise from all. sources near and far. In this
LEVEL:
context, the ambient noise level constitutes the normal or existing
level of .environmental noise a given location.
CNEL:
Community Noise Equivalent Level. The average equivalent sound
level during a 24-hour day, obtained after addition of approximately
five decibels to sound levels in the evening from 7:00 p.m. to 10:00
p.m. and ten decibels to sound levels in the night before 7:00 a.m.
and after 10:00 p.m.
DECIBEL, dB: A unit for describing the- amplitude of sound, equal to 20 times the,
logarithm to the base 10 of the ratio of the reference pressure,
which is 20 micropascals (20 micronewtons per square meter).
I,�;
Day-Night Average Sound Level. The .average equivalent sound .. .
level during a 24=hour day, obtained after addition of ten decibels
to sound levels in the night after 10:00 p.m.. and. before 7:00 a.m.
I, :
Equivalent Sound Level. The sound level containing the same total
energy as a time varying signal over a given sample period. Leq is
typically .computed over 1, S and 24-hour sample periods.
Niue:
CNEL and Ld" represent.daily levels of noise exposure averaged on an annual
basis, while Ley represents the average noise exposure for a shorter time
period, typically one hour.
The maximum sound level recorded during a noise event..
The sound. level exceeded "n" percent of the time during a sample
tLo;
interval. Llo equals the level exceeded 10 percent of the time (Lyo,
L501 etc.)
.
BBAI
_ A-2
ACOUSTICAL TERMINOLOGY
N O I S E E X P O S U R E :' Lines drawn about a noise. source indicating constant.levels of
CONTOURS: noise exposure. CNEL and Ld„ contours are frequently utilized
to describe community exposure to noise'.
SEL OR SENEL: Sound Exposure Level or Single Event Noise Exposure Level.
The level of noise accumulated during a single noise event, such
as an aircraft overflight, with reference to a duration of .one'
second. More specifically, it is the time -integrated A -weighted
squared sound pressure level fora stated time interval or event,
based on a reference pressure of 20 micropascals ' and a
reference duration of one second.
SOUND LEVEL: The sound pressure level in decibels as measured on a sound
level meter, using the A -weighting filter. network. The, A
weighting filter de-emphasizes the .very low and very high
frequency components of the sound in a manner similar to the
response of the human ear and gives good correlation with
subjective reactions to noise.
B
t
r
-
Planning Division.
I F�
SEP
'
Oro v lie, California i
PARADISE AIRPOR
NOISE EXPOSURE CON'S
Butte County, California
...
Prepared For
' . .Butte County
+.
r
3
'
.7 County Center Drive
Oroville CA 95965-3397
-
August 30, 1996
Prepared By,
f
Brown-Buntin Associates, Inc...
Fair Oaks, California...a
y-
.-
... .. . •:� �� r
-.
�
; .
.BSA
. -
5150 Sunrlse'Blvd., Sulte D-3'
• Falr'.oaks, CA 95628 (916) 961-5822,• Fax: (916) 961.6418 '
- 319 West School Ave., Visalia,
CA. 93291 (209) 627-4923 • Fax: (209) 627.6284
• ,
iD
INTRODUCTION:
Brown-Buntin Associates, Inc. (BBA) has completed an analysis.of aircraft/airport operations and
related noise levels for the Paradise Airport. The analysis has been conducted for the preparation
of future year (2005) Community Noise Equivalent Level (CNEL)' noise exposure maps for the
Paradise Airport operations.
The Federal Aviation Administration's (FAA) Integrated Noise Model (INM) Version 5.01 was used
to prepare CNEL noise exposure maps for the Paradise Airport based upon the FAA noise level data
for single engine and twin engine aircraft, and airport operational factors as described below.
The MM was developed for the FAA, and represents the federally -sanctioned and preferred
method for analyzing aircraft/airport noise exposure. Version 5.01 is the currently -available
version of the INM, incorporating an updated data base of aircraft performance parameters
and noise levels.
Projected data for aircraft activity, aircraft fleet mix and airport configuration used in the noise
modeling process were obtained from the most recent (1988) California Aviation System Plan
(CASP), and discussions with the Paradise Airport officials. The following report summarizes
the data, methods and assumptions used in preparing the CNEL noise exposure maps.
The noise descriptor used by the FAA is the Day -Night Average Level (Ldp). The FAA uses the
Day -Night Average Level to describe land use compatibility with respect to aircraft noise exposures.
The FAA airport noise compatibility criterion for residential land uses is 65 dB Ldp. The California
Department of Transportation Division of Aeronautics uses the 65 dB CNEL descriptor to describe _
residential land use compatibility with respect to aircraft noise exposures. Generally, the predicted
Ldp and CNEL values agree within 1 dB of one another.
The CNEL descriptor is a method of averaging single event noise levels over a typical 24-hour day,
applying. penalties to noise events occurring during the evening (7 p.m. to 10 p.m.) hours, and
nighttime (10 p.m. to 7 a.m.) hours. CNEL is usually defined in terms of annual average conditions;
so that the CNEL measured on a given. day may be, either less than or greater than the annual
average.
AIRPORT OPERATIONS:.
Airport operational factors which can significantly affect overall noise levels as.described by CNEL
include the aircraft fleet mix, the number of daily operations and the time of day when aircraft
operations occur. Runway use. factors also significantly influence CNEL values. Trip length can
affect aircraft single event noise levels, as an aircraft which is prepared for a long flight may carry
more fuel and passengers than for a short flight. 'The INM applies corrections to air, carrier aircraft .
takeoff profiles to account for these differences, but makes no corrections to general aviation aircraft
takeoff profiles.
Aircraft operational assumptions for Paradise Airport are based upon analyses of airport activity
provided in the CASP and discussions with the Paradise Airport officials. These assumptions are
. _ described by Tables I and II.
TABLE I
AIRPORT
CONFIGURATION AND USE
Paradise. Airport ,
Configuration:
Runway Configur
2 1 length
17-35 7 0 g
Field Elevation:,
1344' MSL
Runway Use Factors:
50%. Rwy 10
50%"Rwy 28
Distribution Operations:
55% Day /10% Evening/ .5% Night
Traffic Flow by Direction:
To/From South
61%
To Southeast
17%
To"Southwest
17% ,
To/From North
5%
Piper Dipper
Cessna 180
Mooney M20 -C i
Comanche ,
Trip -Pacer
Cessna 120
Piper Arrow. BEECH58P 0'.8' 1.0
Detailed descriptions of aircraft flight tracks were provided by the Paradise Airport. staff. Based
upon these data, BBA prepared generalized flight tracks for use in the noise modeling process to
.describe areas with a concentration of aircraft overflights. Figure 1 shows the flight tracks used for
the noise modeling process.
3
PREPARATION OF CNEL NOISE EXPOSURE MAPS:
' As discussed earlier in this report, the Integrated Noise Model (INM) Version 5.01 was used to
prepare CNEL noise exposure maps_ for the airport; based upon the aircraft noise level and airport.
operational factors described in the previous sections. The INM was developed for the FAA, and ,
represents the federally -sanctioned and preferred method for analyzing aircraft/airport noise'
exposure. Version 5.01 is the most recent version of the INM, incorporating an updated database
of aircraft -performance parameters and noise levels.
The INM calculates aircraft noise exposure by mathematically combining aircraft noise levels and
airport operational factors at a series of points within a cartesian coordinate system which defines,
the location of airport runways and'.aircraft flight tracks. User inputs to the INM include the
following:
a. Airport altitude and mean temperature
b. Runway configuration
c. Aircraft flight track definition
d. Aircraft stage length
e. Aircraft departure. and approach profiles
f Aircraft traffic volume and,fleet mix
g. Flight.track utilization by aircraft types
The INM data base includes aircraft performance, parameters and noise level data for aircraft classes. -
When the user specifies a particular aircraft class from the INM data base; the model automatically
provides the necessary inputs concerning aircraft power settings, speed, departure profile and noise
levels. JNM default values were used for all fixed -wing aircraft types. _
After the model had been -'prepared for the aircraft classes described in the preceding section, BBA
created. INM input files containing the number of operations by aircraft class, time of day and flight
track for annual average day. aircraft operations for the year 2005. The INM was' used with these
operational scenarios to prepare 55, 60 and 65 dB CNEL contours, which have been plotted on'
Figure 2. Total surface areas included in each of these CNEL contours are shown by Table III:
TABLE III'
SURFACE AREAS WITHIN CNEL CONTOURS
Paradise Airp6rt
Area, Square Miles
55 dB
60 dB
65 dB
Scenario
2005
0.16 ' ,
0.66 _
0.02
The shapes' of the CNEL contours are generated by the INM in response to the directional
characteristics of aircraft noise, while the size of the contours is affected by the number of aircraft
operations and the noise emissions of the types of aircraft in the aircraft fleet. Predominant aircraft
arrivals and departures are to and from the south. Based upon discussions with the Paradise Airport
staff, approximately 5 percent of all arrivals are from the north along runway 17, and approximately '
1 percent of departures are to the north along runway 35. Therefore, the noise level contours for the ;
airport are oriented predominantly to the south.
Respectfully submitted,
• Brown-Buntin Associates, Inc.
.Jin -f Brennan
Senior Consultant
Gli POE
MIaM
as
BSA
}
APPENDIX A
ACOUSTICAL TERMINOLOGY
AMBIENT
f
NOISE The composite of noise from all sources near and far. In this.
LEVEL:
context, the ambient noise level constitutes the normal or existing.
level of environmental noise a given location.
CNEL•
Community Noise Equivalent Level. The average equivalent sound
level during a 24-hour day, obtained after addition of approximately
five decibels to sound levels in the evening from 7:00 p.m. to 10:00
p.m. and ten decibels to sound levels in the night before 7:00 a.m.
and after 10:00 P.M.
DECIBEL, dBs A unit for describing the amplitude of sound, equal to 20 times the
logarithm to the base 10 of the ratio of the reference pressure,
which is 20 micropascals (20 micronewtons per square meter). .
Ld.:
Day -Night Average Sound -Level. The average equivalent sound
level during 'a 24-hour day, obtained after addition of ten decibels
to sound levels in the night after 10:00 p.m. and. before 7:00 a.m.
Ley:
Equivalent Sound Level. The sound level containing the same total
energy as a time varying signal over a given sample period. Ley is
typically computed over l,'8 and 24-hour sample periods.
Note:
CNEL and Ld„ represent daily levels of noise exposure averaged on an annual..
basis, while Ley represents the average noise exposure for a shorter time
period, typically one hour.
The maximum sound level recorded during a noise event. .
Lo:
The sound level exceeded "n" percent of the time during a sample
interval. 1-10 equals the level exceeded 10 percent of the time (L90,
L50, etc.)
BSA
}
A.2',.
ACOUSTICAL TERMINOLOGY
NOISE EXPOSURE
Lines drawn about a noise source indicating constant .levels of
CONTOURS:
noise exposure. CNEL and. Ld„ contours are frequently utilized
to describe community exposure to noise.
SEL OR SENEL: • .
Sound Exposure Level,or Single Event. Noise Exposure Level:
The level of noise accumulated during.a single noise event, such'.
as an aircraft overflight," with reference to a duration. of one
second. More specifically, it is the time-integrated A=weighted
squared sound pressure level for a stated time interval or event,
based on a . reference pressure of 20 micropascals` and a
reference duration of one second.
SOUND LEVEL:
The sound pressure level in decibels. as measured on'a sound
level meter using the A-weighting filter network. ' The A-
weighting -filter de-emphasizes the very low and very high
frequency components of the sound. in a manner similar to the. '
response of the human ear and gives good correlation with .
°subjective reactions to .noise.
.. BB