I
\ EPA 550/9-75-024
to
NATIONAL MEASURE
OF AIRCRAFT NOISE IMPACT
THROUGH THE YEAR 2000
JUNE 1975
U.S. Environmental Protection Agency
Washington, D.C. 20460
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Document is available to the public through the National
Technical Information Service, Springfield, Virginia 22151
Document is available in limited quantities through the
Environmental Protection Agency, Office of Noise Abatement
and Control, Arlington, Virginia 20460
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EPA 550/9-75-024
NATIONAL MEASURE
OF AIRCRAFT NOISE IMPACT
THROUGH THE YEAR 2000
JUNE 1975
Carroll Bartel
Larry Godby
Louis Sutherland
Prepared for:
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Noise Abatement and Control
Washington, D.C. 20460
Under Contract No. 68-01-2449
This report has been approved for general availability. The contents of this report
reflect the views of the contractor, who is responsible for the facts and the accuracy of
the data presented herein, and do not necessarily reflect the official views or policy of
EPA. This report does not constitute a standard specification, or regulation.
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Preface
In releasing this report for public availability, some comments are appropriate to
provide the reader with a balanced perspective related to the assumptions and conclu-
sions provided herein.
The data base for this report utilized the noise, performance, and operational
assumptions and forecasts developed for the DOT 23 airport study (Reference 1). That
study was initiated in 1972 and was modified in late 1973. This report therefore re-
flects a set of data available during that time period.
The fleet forecast assumption in Reference 1 (relatively high number of quiet
wide bodies) did not factor-in the effect of the energy "situation" or of the subsequent
economic downturn.
The implementation of SAM retrofit and two-segment approach procedures
were assumed to be initiated by 1/1/75 in the referenced DOT study.
Due to the preceding considerations, the absolute levels of benefit accrued as
a result of alternative actions, as well as the date for their realization, is subject to re-
view. However, the relative relationships among the alternatives should remain con-
sistent with a time phase shift. Also, the benefits of retrofit versus a do-nothing alterna-
tive should be significantly enhanced, since quieter aircraft will not be entering the fleet
as rapidly as indicated in the study.
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ABSTRACT
This program was undertaken for the Office of Noise Abatement and Control,
Environmental Protection Agency, to evaluate the nationwide community impact of
aircraft noise through the year 2000, considering a number of aircraft/airport noise
reduction alternatives. The study was based on the evaluation of operations at three
airports Los Angeles International, St. Louis, and Washington Dulles. Primary noise
reduction alternatives were applied at each of the facilities for the 1987 and 2000 time
periods. Secondary abatement alternatives were evaluated for 1987 only. The effec-
tiveness of the various alternatives was measured in terms of the total area impacted
under the Nth" 3D and 40 contours at the three airports. This area was then increased
by a constant factor to obtain an estimate of the impact at the national level. The
report also contains an estimate of the total area within the NEF 20 contours and the
impacted land area for NEF 20, 30, and 40 exclusive of airport property and water.
This study utilized, in part, the much more detailed results for 23 airports from the
"Airport Noise Reduction Forecast" study recently completed by Wyle for the Department
of Transportation. However, this study differs substantially from the Department of Trans-
portation program in that it is based on analysis at only three airports, includes no cost
or population data, extends beyond the year 1987, and focuses only on estimating trends
in aircraft noise impact to the year 2000 in order to evaluate the potential requirement
for research on new aircraft/airport noise reduction alternatives which may not currently
be under development.
Ill
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ACKNOWLEDGMENTS
The authors would like to express their appreciation to Mr. John Schettino, of the
Office of Noise Abatement and Control, Environmental Protection Agency, for his
encouragement and support throughout the conduct of this study. The helpful suggestions
of Messrs. Harvey Nozick, William Sperry, and Fred Mintz, also of this office, are
gratefully acknowledged. Finally, we wish to thank the other members of Wyle Research
who assisted in the completion of this report.
IV
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TABLE OF CONTENTS
Page
1. INTRODUCTION ............ 1
2. CONCLUSIONS AND RECOMMENDATIONS ...... 5
2.1 Conclusions - Primary Noise Reduction Alternatives ... 5
2.2 Conclusions - Secondary Noise Reduction Alternatives . . 12
2.3 Recommendations .......... 15
3. NOISE ANALYSIS ............ 17
3 1 Mr-.icr, Pc-.rhi.-f;.-,;" A I torn /-!«' ./--=- TO
* i **»».**» !**»* v vi t«*f . * I vi <* V w^ . . . . . . . JU
3.1.1 Primary Alternatives ........ 18
3.1.2 Secondary Alternatives ....... 27
3.2 National Model for Noise Impact Evaluation .... 30
3;2tl Se'ect'on «f Somnle Airport? ; ; t t 32
3.2.2 Extrapolation of Results to the Nation .... 33
4. AIRPORT/AIRCRAFT FORECAST ANALYSIS FOR U.S ..... 38
4.1 Forecast of Fleet and Airport Operations ..... 38
4.1.1 Long Term Fleet Forecast ....... 38
4.2 Forecast of Aircraft Categories ....... 41
4.3 Forecast of Level III Aircraft Characteristics .... 45
4.3.1 Performance Characteristics ...... 45
4.3.2 Aircraft Noise Characteristics ...... 45
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REFERENCES
TABLE OF CONTENTS (Continued)
Page
R-l
APPENDIX A
APPENDIX B
APPENDIXC
APPENDIX D
AIRPORT NOISE IMPACT ANALYSIS
A-l
DETAILED NOISE AND PERFORMANCE CHARACTERISTICS
OF ADVANCED TECHNOLOGY (LEVEL III) AIRCRAFT
UTILIZED FOR THIS STUDY B-l
AIRPORT ACTIVITY DATA
DERIVATION OF CLIMB GRADIENT FOR ENGINE
OUT CONDITION
C-l
D-l
VI
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LIST OF FIGURES
Figure Page
2-1 Estimated Total Area (National) Within NEF Contours for Approach
and Takeoff Noise Reduction Alternatives for 1972, 1987, and 2000 7
2-2 Estimated Total Area (National) Within NEF Contours for Retrofit
Noise Reduction Alternatives for 1972, 1987, and 2000 8
2-3 Estimated Total Area (National) Within NEF Contours for Improved
Technology Noise Reduction Alternatives for 1972, 1987, and 2000 9
2-4 Comparisons of Estimated Total Area (National) Within NEF
Contours Resulting from the Application of Various Secondary
Effect Alternatives for the Year 1987 14
3-1 6°/3° Glide Slope Procedure 21
3-2 ALPA Takeoff Profile 21
3-3 Forecast of U.S. Domestic RPM (Certificated Carriers, Scheduled
Service) 29
3-4 Model for Evaluating Effect of Dispersion of Flight Tracks 31
3-5 Relationship Between Total Area Within NEF 30 Contours and
Total Operations 34
3-6 Relationship Between Total Contour Area for 23 Airports (A?_)
and Three Airports (A,,) 37
4-1 History and Forecast - U.S. Air Carrier Fleet 43
4-2 Three-Engine Wide Body Reference Spectra 47
VII
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LIST OF FIGURES (Continued)
Figure Page
A-1 Relative Change in Total Area Within NEF Contours as a Function
of NEF Value A-2
A-2 Impacted Land Area Versus Total Area for Sums of Areas for
Alternatives and NEF 30 - 45 Values at 23 Airports A-3
A-3 Forecast of Size and Activity of U.S. Air Carrier Fleet A-7
A-4 Cumulative Distribution of Percent of Airports with Air Carrier
Operations Greater Than a Given Number Per Day A-8
A-5 Estimated Percent of Airport Operations Carried Out by
Propeller Aircraft A-11
A-6 Relationship Between Total Contour Area and Equivalent Jet
Operations for the NEF 30, 1972 Baseline Case from the
23 Airport Study A-13
A-7 Airport Area Versus Average Daily Operations for 36 Major U.S.
Air Carrier Airports A-16
A-8 Total Impacted Land Area Plus Water Area Versus Total Contour
Area for All and Seven Smallest of 23 Airports A-17
A-9 Estimated Area Over Water Predicted From Results of 23 Airport Study A-18
B-l Noise Curves for Level III Technology 2-Engine Aircraft B-3
B-2 Noise Curves for Level III Technology 3-Engine Aircraft B-4
B-3 Noise Curves for Level III Technology- 4-Engine Aircraft B-5
B-4 Takeoff Profiles for Level III Technology, 2-Engine Aircraft B-6
B-5 Takeoff Profiles for Level III Technology, 3-Engine Aircraft B-7
B-6 Takeoff Profiles for Level III Technology, 4-Engine Aircraft B-8
VIII
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LIST OF TABLES
Table Page
2-1 Number of Candidate Jet Aircraft for Each of the Retrofit Options
and Total U.S. Fleet Size 6
2-2 Summary of Estimated Impacted Area for Nation Within NEF 20
and 30 Contours Expressed as a Percentage of Impacted Area for
Base Year 1972 13
3-1 Scenarios of Noise Reduction Alternatives 19
3-2 Takeoff Climb Procedures with Reduced Power Setting 20
3-3 Average Climb Gradient end Relative Thrust During Power Cutback
Condition 23
3-4 EPNL Values Relative to Current FAR 36 Limits, dB 26
3-5 AEPNL Corrections Applied Uniformly to Noise Curves to Achieve
FAR 36-X Levels, dB 28
3-6 Summary of Scaling Factors Used to Extrapolate Results to Nation 36
4-1 Forecast of Traffic Demand and Fleet Size 40
4-2 Fleet Forecast Summary Year 2000 44
A-l Analysis of Total and Impacted Area Within NEF 30 for 1972 Baseline
at Air Carrier Airports Excluding the 23 in Reference 1 A-20
A-2 Estimated Total Area (National) and Impacted Area (National) for
Noise Abatement Alternatives for 1972, 1987, and 2000 A-22
A-3 Summary of Raw Data Showing Total Area Within NEF 30 and 40
Contours at Each Airport A-23
A-4 Results of Secondary Alternatives for 1987 A-24
IX
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LIST OF TABLES (Continued)
Table Page
C-la Airport Activity, Los Angeles - 1972 C-2
C-lb Airport Activity Forecast, Los Angeles - 1987 C-3
G-lc Airport Activity Forecast, Los Angeles - 2000 C-4
C-2a Airport Activity, St. Louis - 1972 C-5
C-2b Airport Activity Forecast, St. Louis - 1987 C-6
C-2c Airport Activity Forecast, St. Louis - 2000 C-7
C-3a Airport Activity, Dulles - 1972 C-8
C-3b Airport Activity Forecast, Dulles - 1987 C-9
C-3c Airport Activity Forecast, Dulles - 2000 C-10
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1. INTRODUCTION
Under Section 4(c)(l) of the Noise Control Act of 1972, the Environmental
Protection Agency is charged with the responsibility of coordinating the programs of
all federal agencies relating to noise research and noise control. Since aircraft have
been identified as one of the primary sources of noise, this responsibility includes
formulation of plans relative to the alleviation of noise exposure in the vicinity of
airports. The primary intent of this study is to provide EPA with a rationale for speci-
fying such plans by demonstrating the effectiveness of the various alternatives available
for reducing the impact of aircraft noise including reduction of noise at the source,
modification of operational procedures, and changes in compatible land use.
The analysis of the various noise reduction alternatives was based in part on
the results of an airport noise reduction forecast study for 23 airports recently completed
1*
by Wyle Laboratories for the Department of Transportation. As discussed in the
Wyle/DOT report, the 23 airports are estimated to encompass a majority of the U. S.
population exposed to aircraft noise. Three of these 23 airports were selected in this
study for the evaluation of noise abatement alternatives applied to the years 1987 and
2000. The principal assumptions utilized for these two studies may be compared as
follows:
Wyle/DOT Report Current Report
Number of airports 23 3
Final Year 1987 2000
Baseline for future 6°/3° approach No noise reduction alternatives
years
New aircraft New technology aircraft New technology aircraft constitute
constitute only 8 percent 65 percent of fleet by the year 2000
of fleet in 1987 and are and are assumed to comply with
represented by current FAR 36-10 limits
technology SAM-
retrofitted aircraft
A Superscripts refer to references listed on pages R-l and R-2.
1
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Wyle/DOT Report
Current Report
Air carrier fleet
forecasts
Airport operations
forecasts
Extrapolation of
noise impact to
nation
Estimate to 1987 by
detailed analysis of
required and available
air carrier transport
capacity
Estimate to 1987 based
on detailed analysis of
forecast passenger and
cargo traffic at each
airport and aircraft
capacity by type
Not attempted
Extrapolation beyond 1987 with
gradually reducing rate of growth
of required capacity, and unit
productivity
Extension of forecasts to year 2000
considering growth in aircraft
capacity, and improved operating
efficiency of airports
Extrapolation to nation based on
evaluation of current and forecast
profile of air carrier airports by
number of operations
The three airports Los Angeles International. St. Louis, and Dulles were
chosen on the premise that they were generally representative of air carrier airports
as defined by their respective operational categories, i.e., greater than 250,000
annual operations, between 100,000 and 250,000, and less than 100,000 annual
operations, respectively. This grouping was based on an analysis of air traffic activity
at 350 air carrier airports for 1972.
The analytical model to compute the reduction in noise exposed area incor-
porates the baseline plus six primary reduction alternatives for the projected operating
levels in 1987 and 2000 plus four secondary alternatives applied in 1987 only. These
alternatives are listed as follows:
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Primary Alternatives
o Baseline aircraft,* standard operating procedures
6°/3° glide slope approaches
Power cutback takeoffs
Quiet nacelle treatment (identified as SAM Sound Absorption Material)
to aircraft equipped with JT3D and JT8D engines for both standard
3° and 6°/3° glide slope
e Engine modification (identified as REFAN) of all 727-200 and DC-9
aircraft and SAM treatment of all JT3D, 727-100 and 737 aircraft.
a SAM treatment of all JT3D aircraft and REFAN treatment of all
JT8D aircraft
© Aircraft noise levels at 5, 10, 15, and 20 a'B below current FAR 36
aircraft levels applicable to all air carrier aircraft operating at
U.S. airports.
Secondary Alternatives
« Uniform percentage changes in fleet size
e Changes in flight procedures (flight track scatter)
« Changes in fleet composition
Night curfew
Total area within NEF 30 and 40 contours is evaluated as well as the impacted
land area for the three airports and subsequently applied in the development of a nation-
wide impact model. For this study, the impacted land area is defined as the total area
within a contour less the airport and water area within the same contour.
The results of this study and recommendations are summarized in Section 2 of
this report. The noise analysis and aviation system analysis elements of the study are
presented in Sections 3 and 4. Additional supporting data are provided in the appendices.
Baseline aircraft assumes normal attrition and replacement forecast.
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The conclusions and recommendations made in this report, although based on a
limited sample, are believed to be representative on the broader national scale within
the constraints of the assumptions applied.
Recognizing these limitations, however, the general conclusions and change
in values of estimated noise impact are considered reasonable to the year 1987 (assuming
no major technological breakthroughs or unforeseen societal changes occur). The current
emphasis on fuel conservation could have an impact on the study results. However, the
consideration of the secondary alternatives, such as the effects of fleet size or fleet
composition, as discussed in Section 3, provide some insight into the possible effects
of ti long range energy conservation program. Although Jess confidence must be assigned
in the 26-year projection to the year 2000, the relative ranking of the effectiveness of
the various alternatives is considered sufficient to serve as a valid guideline for long
range research planning.
It should be pointed out that this analysis of aircraft/airport noise impact
accounts only for the principal component based on today's trends, mainly noise impact
around air carrier airports served by conventional takeoff and landing jet aircraft. The
additional components of aircraft noise impact attributable to military, general aviation,
or V/STOL aircraft are not included in this study. With the possible exception of noise
impact from future V/STOL airports, these components are expected to be relatively
small compared to the problem considered in this study.
Finally, it must be emphasized that the estimates of total impacted area should
be interpreted in terms of relative changes rather than absolute values. This qualification
is consistent with the basic intent of NEF contours as quantitive guides for planning and
not precise measures of noise impact.
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2. CONCLUSIONS AND RECOMMENDATIONS
This section summarizes the principal results of this study and outlines some
of the problem areas which were beyond the scope of the study and which should be
evaluated in the future.
2.1 Conclusions Primary Noise Reduction Alternatives
The primary noise reduction alternatives listed in the previous section were
evaluated in a series of scenarios of progressively greater noise reduction. This was
achieved by evaluating the cumulative effect of combining two or more alternatives
with greater and greater noise reduction potential. The effectiveness of each of these
scenarios is evaluated in terms of the total area, extrapolated to the nation, within
the NEF 30 and 40 contours for each time period.
Table 2-1 summarizes the number of aircraft for the years 1987 and 2000 for
which the SAM or REFAN Retrofit alternatives are applied as well as the total aircraft
ri«_». _:.. p: o i 1 o o :ii...<._.,<.,. «.u~ «.: *,J r *i .»_:rt. _tr d 1
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operational alternatives currently under active development or consideration which
were considered in this study. Note that while the time of initial effectiveness of the
various alternatives are only approximate, an attempt has been made, for this study, to
estimate the shape of the transition in noise-impacted area between these initial years
and the year 1987. For the year 1987, the various scenarios of noise reduction alterna-
tives differ substantially in absolute and relative effectiveness. By the year 2000, the
alternatives do not differ in effectiveness nearly as much from each other nor do they
achieve in total as much relative reduction. This is primarily because most of the
current technology aircraft will have been retired and replaced-by quieter new tech-
nology aircraft which comply with FAR 36-10 limits. In this case, the relative benefits
of two-segment approach or power cutback are reduced.
Figure 2-3 illustrates the time trend for the nonspecific improved technology
(aircraft noise level) alternatives in combination with the 6°/3° glide slope and power
cutback alternatives. In this case, even with the substantial initial effectiveness of
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Table 2-1
Number of Candidate Jet Aircraft for Each of the Retrofit
Options and Total U.S. Fleet Size (From Reference 1 and 3)
Technology
0
I
11
III
IV
I
ii
in
IV
Year
1987
2000
Aircraft Type
Propeller
4 Eng NB (707/DC-8)
3 Eng NB (727)
2 Eng NB (737/DC-9)
4 Eng WB (747)
3Eng WB(DC-lOA-lOll)
2 Eng WB (A300)
100-250 Seat(°)
S5T
Total
Narrow Body
4 Eng WB
3 Eng WB
2 Eng WB
100-250 Seat(b)
250-400 Seat(c)
>400 SeatsW
SST
Total
Number of Aircraft
in Fleet Retrofitted
SAM
-
170
341
407
-
-
-
918
-
-
-
REFAN
-
458
407
-
-
-
865
-
-
-
Total
Fleet Size
78
170
601 (°>
492(a>
660
1470
445
350
125
4391
325
600
500
400
1625
1300
1300
450
6500
Includes new aircraft not candidates for retrofit.
' 'Range, 0-500/500-2500 miles (short and medium range).
^Range, 500-2500 miles.
*d'Range, >2500 miles.
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«'««" E - SAM 30/80. 4V3', PCS (R»f«r.rK.)
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1972 1975
1980
1985 1990
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1995
2000
Figure 2-3. Estimated Total Area (National) Within NEF Contours for
Improved Technology Noise Reduction Alternatives for
1972, 1987, and 2000
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the two operational procedures and the projected conversion of the entire fleet to
quieter aircraft, these alternatives show a high degree of noise reduction effectiveness,
particularly for the year 1987 when, without retrofit or improved technology assumptions,
there would still normally be a substantial number of aircraft in the fleet not complying
with FAR 36 levels. However, it must be emphasized that the resultant impact data for
each alternative is an optimistic projection, i.e., the entire fleet meets or exceeds the
assumption criteria of the given point in time. Practical economics may, in fact, pre-
clude this from occurring, thereby slipping the effectivity date. Nevertheless, the
results of this projection indicate the potential for improved airport noise environments
achievable in the future by various assumed alternatives.
Since no data were analyzed for the time period between 1972 and 1987 in
this report, the trend lines indicated in Figures 2-1 to 2-3 were estimated, using data
from the Wyle/DOT 23 Airport study as a basis. For that period, the "B" trend line
(Baseline Aircraft, 6°/3° Approach) was estimated for the 1978 and 1981 time periods
by extrapolating the results of the 23 Airport Study to the nation on the basis of equiva-
lent aircraft operations as explained in Section 3.2.2 and in Appendix A. Having these
estimates, values for the "A" trend line (Baseline Aircraft, 3° Approach) were computed
for 1978 and 1981 by assuming that the percentage separation between these two lines
would be constant and the same as the percentage separation in 1987. A straight line
estimate was, assumed from 1972 to 1978 for the "A" trend line. The 6°/3° approach
alternative was assumed to be initiated by year end 1974 and in full operation by year
end 1978. Points for the "C" trend line (Baseline Aircraft, 6°/3° Approach, Power
Cutback (PCB)) were generated for 1978 and 1981, using the same percentage comparison
method with the "B" trend line. In a similar manner, the "D", "E", and "F" trend lines
were constructed with points computed for appropriate time periods. For the trend lines
representing retrofit categories, points were estimated for the transitional period from
start of retrofit to completion, using the implementation schedule specified in Reference 1,
and lines were faired using these points to estimate rhe trends over the entire implemen-
tation period. For the trend lines representing the FAR 36-5 and -10 options, the
10
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SAM 3D/8D, 6°/3°/ PCB trend (line E) was assumed up to 1978 and the percent
accomplishment of the difference between the 1978 and 1987 values was assumed to
be 20 percent by 1981, 50 percent by 1984, and 100 percent by 1987. It was assumed
that the FAR 36-15 and -20 options would not be initiated until after 1987. For all
cases considered, straight lines were used to represent the trends between 1987 and 2000.
The following explanation gives the rationale for the trend variations in
Figure 2-3 between 1987 and the year 2000 for the cases involving FAR 36-X.
There are three counteracting factors which can influence these trends in
4^>4-/'-»j .-- « .*v»"i f'rf"
I VS* V* I \^\SI I I
1) A tendency to increase from 1987 to 2000 due to increased number of
operations. This influence is constant for all four FAR 36-X cases between
1987 and 2000 in Figure 2-3.
")\ .A t£»>de!"!Cv/ to decreose from 1987 to 2000 due to the normo! ottrltior! of
the noisier Level I and II technology aircraft and replacement by the
quieter Level III technology aircraft. This influence is also constant for
all four FAR 36-X cases between 1987 and 2000.
3) A tendency in the FAR 36-X trend lines to decrease as X is increased
because the number of aircraft involved by each FAR 36-X level changes
from 1987 to 2000. For example, the imposition of FAR 36 -5, and -10
levels would affect 26 percent and 90 percent of the fleet, respectively,
in 1987 while these same levels would affect only 12 percent and 35
percent, respectively, of the fleet in the year 2000. One hundred percent
of the fleet would be affected by FAR 36 -15 or FAR 36 -20 levels in the
year 2000.
11
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The combined action of these three factors results in the trends observed. The first
two factors nearly balance out for the FAR 36 -5 level which influences a relatively
small part of the fleet in both 1987 and 2000. For the FAR 36 -10 level, however,
a major part (90 percent) of the fleet is influenced in 1987 but much less (35 percent)
is influenced in 2000 so that the net effect of more operations and less aircraft affected
overrides the downward tendency from quieter aircraft and results in a net trend upward
in this case. The overriding influence of the FAR 36-15 and -20 levels on all the fleet
result in a net downward trend in both cases.
A desirable national goal could be to reduce the impacted land area within
NEF 20 (~L , 55) contours to zero by the year 2000. Estimates of the impacted area
(excluding airport property and area over water) within NEF 20, 30, and 40 are pre-
sented in detail in Appendix A and are briefly summarized in Table 2-2 for NEF 20 and
30 contours. Even with the FAR 36-20 aircraft noise level alternative there is an esti-
mated remnant of about 310 square miles of impacted lend within the NEF 20 contour
by the year 2000. However, this is a reduction by a factor of about 35 from the esti-
mated 11,000 square miles of impacted land within NEF 20 contours around air carrier
airports today. The relative changes in estimated impacted land area in Table 2-2
clearly indicate the substantial downward trend in airport noise projected for the future
due to the present transition to quieter wide-body aircraft and the forecast transition
to new technology (FAR 36-10) aircraft in the future. Thus, an effective long-term
resolution of the problem of airport noise impact will require additional noise reduction
developments beyond current technology in order to counteract the projected reescalation
of noise due to future air transport demand.
2.2 Conclusions Secondary Noise Reduction Alternatives
The estimated total contour area, on a national basis, for various secondary
noise reduction alternatives in combination with the two-segment approach alternative,
is shown in Figure 2-4. These alternatives indicate the general sensitivity of the final
result to changes in some of the key assumptions made in the study, as well as indicating
12
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Table 2-2
Summary of Estimated Impacted Area for Nation Within
NEF 20 and 30 Contours Expressed as a Percentage of
Impacted Area for Base Year 1972*
Alternative
No Change - Base r\ii~crufi
6°/3°
PCB + 6°/3°
SAM 3D/8D
SAM 3D/8D + PCB, 6°/3°
SAM 3D, REFAN 8D + PCB, 6°/3°
FAR 36-5 + PCB, 6°/3°
FAR 36- 10 + PCB, 6°/3°
FAR 36- 15 +PCB, 6°/3°
FAR 36-20 + PCB, 6°/3°
1987
NEF 20
69%
65%
53%
58%
39%
25%
20%
10%
-
NEF 30
72%
67%
52%
61%
39%
23%
17%
7%
-
2000
NEF 20
29%
26%
24%
29%
24%
23%
20%
16%
7%
3%
NEF 30
27%
24%
22%
27%
22%
20%
17%
13%
5%
1%
Base impact area for 1972 = 11,000 and 1,800 square miles inside NEF 20 and
30 contours, respectively, for nation, excluding airport property and water.
Based on detailed data in Table A-2, Appendix A.
13
-------
3000
cr
cr>
D
o
z
c
IE
o
s
o
0
o
"o
2000
1000
Reduction due
- to6°/3°
T
Alternatives
A - Baseline Aircraft, 6°/3° Approach (Reference)
B - 10% Flee! Reduction (uniform for all a/c types]
C - 10% Fleei Increase (uniform for all a/c types)
D - 50% Narrow Body Aircraft Reduction*
E - 50% Narrow Body Aircraft Increase *
F - Narrow Body Operations Restricted to Daytime
Hours (0700-2200)
G - All Aircraft Operations Restricted to Daytime
Hours
* Seat capacity maintained by adjusting number
of wide body aircraft.
- Reduction due to
6°/3°
DTL
C D E
NEF30
C D E
NEF40
Secondary Alternatives
Figure 2-4. Comparisons of Estimated Total Area (National) Within NEF Contours Resulting
from the Application of Various Secondary Effect Alternatives for the Year 1987
-------
the effectiveness of night curfew alternatives. The substantial influence of the per-
centage of narrow body aircraft and night curfew procedures is quite apparent. The
effect of flight track dispersion, not illustrated in Figure 2-4, was relatively small
for the lower noise levels. A 9-degree dispersion in takeoff or approach paths produced
a 3.7 percent decrease in area within the NEF30 contour. These results are based on a
simplified analysis and are only intended to indicate trends.
2.3 Recommendations
The results of this forecast study on noise impact around the nation's airports
can provide a useful insight into the effectiveness of many of the aircraft/airport noise
reduction alternatives under consideration, it is recommended that an additional effort
be carried out to improve the utility and validity of these projections. The areas for
further study would include:
o Refinement of the secondary reduction alternative analyses to evaluate,
more completely, the effects of variations in the basic study assumptions.
o Evaluation of trends in noise impact for the entire aviation system, i.e.,
include military (including joint use) and general aviation airports.
e Evaluation of effectiveness in terms of projected number of people impacted
using forecasts of population trends around a sample of airports.
o A more detailed evaluation of the amount of compatible land within pro-
jected contours for all of the nation's airports (i.e., refinements in the
national airport noise impact model).
» A detailed evaluation of the potential effectiveness of a Fleet Noise Level
(FNL) taking into account the principle that the noise level of any given
fleet is a function of the engine noise of each aircraft in that fleet and
the total number of takeoffs and landings of each aircraft in that fleet:
1) determine the noise levels of each aircraft in that fleet; 2) determine
the total number of operations (takeoffs and landings) for each aircraft
15
-------
type for a representative 90-day period; 3) calculating FNL as a mean
logarithmic value; and 4) establishing a precise limit on fleet noise
levels. The simplified analysis carried out in this study of several versions
of an aircraft noise limit indicates the potential benefits that might be
achieved by such noise regulations.
16
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3. NOISE ANALYSIS
The analysis of airport noise impact is based on the development of contours
of equal Noise Exposure Forecast (NEF) around three sample airports (Los Angeles Inter-
national, St. Louis, and Dulles). These results, in conjunction with the results of
Reference 1, were then utilized in the development of the national impact estimate.
The analysis is divided into three basic categories of aircraft noise reduction effects.
1) Baseline fleet mix in which no change in aircraft or operational
practices occur except normal transitions to quieter aircraft that
have already been initiated and were extrapolated to the future.
2) Progressive application of primary noise reduction aiternatives.
3) Application of secondary alternatives in combination with the two-segment
approach.
The impact analysis is based on actual operational data in the 1972 baseline
east; uuu un flcei unu upeiciiiona! Torecasb provided uy R. Dixon Speas Associates for
3
1987 and 2000. Forecasts include type of aircraft (existing and new generation
replacement aircraft), aircraft mix, stage lengths, and day/night ratios for each of
the three airports. The baseline NEF contours for 1987 and 2000 were then modified
to reflect the five primary noise reduction alternatives. The 1987 case was further
analyzed to reflect the secondary alternatives. Analyses were made of the total impact
area change resulting from the individual and cumulative effects of applying the alterna-
tives. The impact was analyzed primarily in terms of the total area within NEF 30 and
40 contours and included estimated areas down to NEF 20 ( i.e., ~ L , 55). Additional
v dn
evaluation of the results provided an estimate of the impacted land area within these
contours exclusive of airport property and area over water.
17
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3.1 Noise Reduction Alternatives
The various noise reduction alternatives applied in this study are defined
below. The scenarios of progressive application of these alternatives, which were
used for the noise analysis, are summarized in Table 3-1. A baseline set of contours
was also developed for each time period, i.e., a reference base situation reflecting
no noise reduction practices against which all primary noise reduction alternatives
were compared. The reference condition for the secondary alternatives consisted of
the baseline aircraft using a two-segment approach procedure.
3.1.1 Primary Alternatives
Baseline
Using the operating levels for 1972 and those forecast for 1987 and 2000,
it was assumed that aircraft use ATA takeoff procedures defined in Table 3-2 and a
3° glide slope for all approaches.
6°/3° Glide Slope
Using the operating levels forecast for 1987 and 2000, the aircraft were
assumed to use a 6°/3° glide slope on approach. This procedure involves intercepting
the 6° portion of the glide slope at an altitude of 3000 feet or above, then descending
at a 6° angle until reaching an altitude of 690 feet where the transition to the 3°
portion begins. The aircraft is established on the 3° glide slope at or above an alti-
tude of 500 feet. The 3° descent angle is maintained until touchdown. The procedure
is approximated by straight line segments for the NEF computer program model as shown
graphically in Figure 3-1. Normal aircraft approach intercepts for a 3° glide slope at
the three study airports occur at 2500 to 3500 feet altitude, depending on the ground
track. For the 6 /3° glide slope procedure, the 6° portion of the approach is initiated
at a minimum of 3000 feet. This necessitates adjusting the entire traffic pattern existing
at each airport, so that the minimum intercept occurs at 3000 feet. Therefore, the intercept
altitude for 6°/3° glide slope occurs at 3000 feet to 4000 feet for Los Angeles Inter-
nationa! and D-jIbc and at 2000 feet for St. Lc^is.
18
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Table 3-1
Scenarios of Noise Reduction Alternatives
Noise Reduction Alternatives
Primary
Baseline - 3°, Approach
Operational - 6°/3°, Approach
- PCB, Takeoff
Nacolle - 3D
Treatment .. 8D (A|| TyF=s)
- 737/727-100 Only
Refan - 8D
- 727-200/DC-9 Only
Aircraft Noise- 5 dB
(FAR-36) -10dB
-15dB (2000 only)
-20 dB (2000 only)
Secondary
Fleet Size (±10 Percent Change)
Scenarios oF Alternatives
1972
1
X
1987 and 2000
2
X
3
X
X
X
4
X
5
X
X
6
X
X
X
X
7
X
X
X
X
X
8
X
X
X
X
9
X
X
X
10
X
X
X
11
X
X
X
12
X
X
X
Fleet Mix (±50 Percent Change in Narrow Body Aircraft)
Dispersion in Flight Tracks (9 Degrees)
Night Curfew - No Narrow Body Nighttime Flights
Night Curfew - No Nighttime Flights
1987 Only
13
X
X
14
X
X
15
X
X
16
X
X
17
X
X
19
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Table 3-2
Takeoff Climb Procedures with Reduced Power Setting
(from References 4-6)
Segment
1
2
3
(Cutback)
4
Parameter
Alt
Pwr
Speed
Flaps
Alt
Pwr
Speed
Flaps
Alt
Pwr
Jp£cil
Flaps
Alt
Pwr
Speed
Flaps
ATA
0-1500'
Takeoff
2V2 + 10 kts
Takeoff
^
r
1500-3000'
^ Climb Pwr
v.\ /-.
V - , £
j. Irt l.i.
1 ^f tMrf
Optimum
9 >3000'
Climb
250 kts
Retract on
Schedule
ALPA*
0-400'
Takeoff
V2 + 10 to 20 kts
Takeoff
400-1500
Takeoff
Accelerating.,
Retracting
1500-4000'
Thrust required for
one engine out
gradient.**
. Tin l.i.
tf £. < ^ K.,*
Up
> 4000'
Climb
1 210 kts
i Up
FAR 36
0-1000'- 3 eng. or less
0-700' -4 eng.
Takeoff
V2 + 10 kts
Takeoff
T
1000'(min
700' (min
r
^-3eng. or less
-4 eng.
Thrust required for
level flight (one engine
out) but not less than
thrust for 4% gradient
\ * , * ** i.*-
c v- > ii/ ""
Takeoff
i
r
*Refer to Figure 3-2.
Climb gradient y' (with one engine out) not less than:"
1.2% for 2-engine aircraft
1.5% for 3-engine aircraft
1.7% for 4-engine aircraft
Climb gradient (all engines operating) y = ?. +(TTT) "T (derivation from Appendix D
~ ...!«.L i /r\ - irv\
12.4% for 2-engine aircraft
7.3% for 3-engine aircraft
5.6% for 4-engine aircraft
with L/D = 10)
20
-------
3000' Minimum
Intercept Altitude
Figure 3-1. y"/3" Glide Slope Procedure
Lift Off
Gear Up
V2 + 10 to 20 kts
Reduced Thrust
and Gradient
210 kts
Climb Out
210 kts
Figure 3-2. ALPA lakeofF Profile
21
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Power Cutback
The noise abatement procedure, recommended by the Air Transport Association,
is currently used during takeoff at many air carrier airports. However, it was recognized
that this procedure does not provide as much noise reduction as a) the procedure recom-
mended for a noise reduction power cutback (PCB) by the Airline Pilots Association
(ALPA) or b) the PCB procedure allowed for a FAR 36 aircraft noise certification. The
basic characteristics of each of these procedures are summarized in Table 3-2 which
defines the flight parameters for each of the segments of the takeoff profile illustrated
in Figure 3-2.
For this study/ the minimum power setting employed during power cutbviclc
was that which just allowed level flight with critical engine out. As illustrated in
Table 3-3, this procedure resulted in a varying climb gradient and thrust, relative to
maximum takeoff thrust, depending on the number of engines. As indicated in the
last column, the average climb gradient during power cutback for 2-, 3-, and
4-engine aircraft was close to that given by a simple aerodynamic performance model
developed in Appendix D which predicts that for all engines operating at the power
necessary to maintain level flight with critical engine out, the gradient is
Climb Gradient = 100 , percent
where N = number of engines.
The values of the predicted gradients given in Table 3-3 are based on a typical
lift to drag ratio of 10 to 1. The resulting climb gradient meets the FAR 36 requirements
for 2- and 3-engine aircraft and is about 20 percent below the FAR 36 requirements for
4-engine aircraft. The gradients are also about 35 to 40 percent below those indicated
for the ALPA power cutback procedure in Table 3-2. Although climb gradients for
4-engine aircraft are not exactly compatible with FAR 36, the difference in noise impact
22
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Table 3-3
Average Climb Gradient and Relative Thrust
During Power Cutback Condition
Number
or
Engines
(N)
2
3
4
Reduced T'nrusi
Maximum Takeoff Thrust
Minimum T.O.W.
0.74
0.61
0.47
Maximum T.O.Wo
0075
0.68
0.64
Ciimb Gradient
*
Average
%
9.3
5.3
3.2
**
Predicted
%
10
5
3.3
Average values for all Level I and II (current technology) aircraft for minimum
and maximum takeoff weight (T.O.Wo).
**Predicted climb gradient = 100[1/(N-1)3 (Drag/Lift) for .power setting equal
to that required to maintain level flight with critical engine out.
23
-------
is not large since 4-engine narrow body aircraft constitute less than 4 percent of the
total fleet in 1987 and even less in 2000. Therefore, the cutback procedure used here
is considered essentially equivalent to that allowed by FAR 36.
The ALPA procedure corresponds to a climb gradient defined in Table 3-2.
Thus, the ALPA power cutback procedure would be expected to produce slightly less
noise reduction than that employed in this study. Based on the decreased reduction in
thrust that would be allowed, it is estimated that ALPA power cutback procedures would
produce approximately 75 percent of the reduction in impacted area computed by the
power cutback procedures followed in this study.
The benefit of pc\ver cutback in tnkecff procedures is greatest in the 1972 to
1987 period and diminishes as the year 2000 is approached. This occurs because the
JT3D and JT8D engine takeoff noise can be reduced significantly with power cutback.
After 1987V, all aircraft produced conform to FAR 36 requirements or better .and hence
the benefit of power cutback decreases.
o Quiet Nacelle
The quiet nacelle or SAM treatment, analyzed in Reference 1, for current
technology narrow body aircraft, was applied to all JT3D and JT8D aircraft in combina-
tion with either the standard 3° glide slope during approach or the combination of the
6°/3° glide slope and power cutback on takeoff.
* REFAN
This condition was evaluated by applying engine REFAN modifications, also
evaluated in Reference 1, for current technology JT8D-powered narrow body aircraft
(i.e., 727, 737, and DC-9) and applying the quiet nacelle treatment to all JT3D air-
craft (i.e., 707, DC-8). A second REFAN case was also developed by refanning only
the 727-200 and DC-9 aircraft and applying the quiet nacelle (SAM) treatment to the
727-100, 737, and all the JT3D-powered aircraft.
24
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e Aircraft Noise Level
Up to this point, the noise reduction alternatives considered have consisted
of available operational procedures or aeronautical system changes currently being
developed. In order to examine the potential effectiveness of further noise reduction
steps, a series of progressively greater reductions (i.e., -5 to -20 dB) relative to
current FAR 36 certification limits were explored. This study did not attempt to
determine the feasibility or practicability of achieving these arbitrary reductions in
aircraft noise levels. Rather, the objective was to develop a better perception of
the relative noise reduction value of these alternatives if, in fact, they were to
become available in future years.
The following procedure was used to evaluate the aircraft noise level alterna-
tive. The basic approach consisted of uniformly reducing the noise level characteristics
of each type of aircraft by the amount necessary for the revised noise levels to conform
to FAR 36-5, -10, -15, or -20 certification levels. Table 3-4 defines the approximate
noise level, in terms of EPNL values relative to FAR 36 limits, for each type of aircraft
and two FAR 36 measurement positions.* The relative EPNL levels are specified, in all
cases, for the baseline unmodified aircraft. Relative EPNL values are also specified
for existing narrow body aircraft in the SAM or REFAN configurations. It can be seen
from the data in Table 3-4 that when SAM or REFAN alternatives are applied, the
resulting aircraft noise levels would either equal or fall significantly below FAR 36
criteria for many aircraft types. For example, the 727 easily meets a FAR 36 -5 level
for the REFAN option at all FAR 36 measurement locations. However, the same aircraft
would not meet a FAR 36-10 in the approach and takeoff mode. Thus, referring to the
REFAN column under Approach for the 727, the relative EPNL level is 7 dB below
existing FAR 36 levels so that an additional 3 dB decrease in level would be required
to achieve a FAR 36-10 limit. This 3 dB correction was applied (uniformly at all dis-
tances and at all thrust levels) to the existing REFAN noise versus slant range curves to
achieve the desired FAR 36-10 limit on approach. This simple correction process to
*The sideline FAR 36 position is not listed since relative FAR 36 aircraft noise levels
at this point we re always less llioii relntivc levels for apfjr<_'Gc!'i or lukeoff positions.
25
-------
1
Table 3-4
EPNL Values Relative to Current FAR 36 Limits, dB'
(All Numbers Calculated from Noise and Profile Curves
2
in Reference 7 or Appendix B)
FAR 36 Position
^^x.^ Alternative
Aircraft ^^^^^
DC -9
737
727
DC -8 (Turbo fan)
707 (Turbo fan)
PC-10
747
L 1011
2 Eng. Wide Body
Level III, Small
Level 111, Medium
Level III, Large
Approach
-------
achieve a specified level below current FAR 36 requirements resulted, as expected,
in hypothetical aircraft noise characteristics which just met the desired limit at one of
the three certification points but usually fell well below the allowed limits at the
other points. This same process was followed for each aircraft type and revised FAR
36 levels to obtain the hypothetical noise performance curves that would comply with
the respective lower FAR 36 limits. Note that, for the existing narrow body aircraft,
the retrofit configuration with the lowest levels (SAM or REFAN as appropriate) was
used arbitrarily as the starting point to achieve levels below FAR 36 and further noise
reductions were then assumed as required.
The resulting changes in EPNL level and the configuration to which they
v/erc applied tc achieve the various aircraft noiss level alternatives are summarized
in Table 3-5. In all cases, each of these alternatives was combined with the 6°/3°
approach and power cutback alternative for evaluation in the program.
3.1.2 Secondary Alternatives
In order to evaluate the sensitivity of the results to small variations in some
of the key air traffic parameters and to explore other possible operational noise
reduction alternatives, the following secondary alternatives were evaluated.
Fleet Size and Load Factor
The fleet size as projected to the year 1987 was modified by a factor of ±10
percent. This appears to be a reasonable range of possible error based on historical
g
forecasts and probabilities of air traffic demand (see Figure 3-3). For a constant
air carrier passenger demand, the fleet size will vary inversely with the load factor
as expressed by the formula:
r-i r Demand
Fleet Size (in number of available seats) = . ^
Thus, a 10 percent decrease in fleet size corresponds to a 10 percent increase in
load factor for a constant demand. In either case, the changes in fleet size or load
27
-------
Table 3-5
AEPNL Corrections Applied Uniformly to Noise Curves to
Achieve FAR36-X Levels, dB
Aircraft
DC-9*
737*
727*
DC-8*
707*
DC-10
747
L1011
2 Eng. Widebody
Level III, Small
Level III, Medium
Level III, Large
FAR 36-5
REFAN-3
REFAN-3
REFAN-0
SAM-3
SAM-3
-1
-2
-1
-2
0
0
0
FAR 36-10
REFAN-8
RE FAN -8
REFAN-3
SAM-8
SAM-8
-6
-7
-6
-7
0
0
0
FAR 36-15
RE FAN- 13
REFAN-13
REFAN-8
SAM- 13
SAM- 13
-11
-12
-11
-12
-4
-5
-5
FAR 36-20
REFAN-18
REFAN-18
REFAN-13
SAM- 18
SAM-18
-16
-17
-16
-17
-9
-10
-10
*
REFAN and SAM indicate to which noise curve sets the given modifications
were applied. (Reference 7)
28
-------
O
ca
v>
V
0)
O)
c
JP
c
-------
factor were evaluated by varying the number of operations, assuming a constant
demand and constant fleet mix.
Fleet Composition
The basic variation applied here was a +50 percent change in the number of
narrow body aircraft in the national fleet. It Is obvious that the fleet size is signifi-
cantly affected through this manipulation. The fleet size was modified so that total
seats available was maintained constant by adding or subtracting corresponding wide
body aircraft to make up for the change in the number and seating capacity of narrow
body aircraft.
Flight Track Scatter
Flight track scatter is demonstrated using a hypothetical airport configuration
but applying the Dulles 1987 operating levels and aircraft mix. Two cases are evalu-
ated for a two-runway configuration one runway perpendicular to the other, as shown
in Pinnrti .14rt Tlio Fircfr rnta ronr/iconfc ri c!r>nlia ctrni/iM ir> fni-ir»rr>/i/~l-i\ <-i"d «'f ^fn!re«-»ff\
a--- ~ - .-,-. '- ..I.-,.- _.._!-,[ v-rr.~ 1 -..i_ . v. .,
track for each runway. The second reflects 20 tracks for each runway, with 9 incre-
mental one-degree left and right turns on approach and takeoff, as seen in Figure 3-4b.
Night Curfews
Two night restriction alternatives are evaluated. The first reassigned all narrow
body aircraft operating between 2200 - 0700 hours to daytime (0700 - 2200) operation.
The second represents a total ban on night operations for all aircraft, reassigning these
to daytime operations. In both cases, fleet mix and available air carrier capacity
remain constant.
3.2 National Model for Noise Impact Evaluation
The evaluation of the noise impact on the national level involved the following
basic steps.
30
-------
A
i
a) Straight Flight Tracks
4nii i '( *i
b) Track SeporoMon 1
Figure 3-4. Model for Evclucting Effect or Dispersion of Flight Tracks.
31
-------
]. Selection of a representative sample of airports for analysis. (The resources
for this program necessarily limited the approach to an analysis of a few of the 23 airports
studied in the Airport Noise Reduction Forecast program. )
2. Extrapolation of the results for the sample airports to an estimate for
the nation.
3. Extrapolation of the analysis carried out for total areas within the NEF 30
and NEF 40 contours to estimate the total area within the NEF 20 contours. The latter
NEF value can be considered as approximately equivalent to the Day-Night Average
Sound Level (L , ) of 55 dB recently identified as a possible lower limit for outdoor noise
to protect health and welfare with an adequate margin of safety.
4. Estimation of the area within the NEF 20, 30, or 40 contours excluding
airport property and water, i.e., impact area.
The first two steps are treated in this section since they represent the two
basic steps required ro obtain rhe fundamental torai area values within rhe NEF 30 or
40 contours. The remaining two extrapolation steps are discussed in Appendix A.
3.2.1 Selection of Sample Airports
Annual level of operations was the sole criterion for selecting a sample of
three airports for analysis. For the year 1972, Los Angeles International (LAX) was
considered representative of airports with greater than 250,000 operations, St. Louis
(STL) represented the airports between 100,000 and 250,000 operations, and Dulles
(IAD) represented those with less than 100,000 annual operations. To examine validity
of this sample, data from the 23 Airport Study were used to relate the total area within
the NEF 30 contour to the number of operations. These data included the airports con-
sidered in this study, since the three airports selected are part of the 23. The general
agreement between calculated areas versus operations for LAX, STL, and IAD and the
corresponding least square regression lines computed for all 23 airports was generally
good and improved as one proceeded from 1972 to later years and as aircraft noise
32
-------
A - A
N Ref
NN(eq)
. NRef(eq).
levels decreased (see Figure 3-5). This evaluation indicated that LAX, STL, and
IAD represented a reasonable sample of airports to use in formulating a national model.
However, it also was apparent that the most accurate estimate for a 1972 national base-
line would be best provided by using the data from Reference 1 for all 23 airports.
3.2.2 Extrapolation of Results to the Nation
After considering several methods for extrapolating results for the three airports
to an estimate for the nation, the following simple scaling procedure was chosen as the
most straightforward and practical for this study.
For any given year and alternative, the area A., within an NEF contour for
the nation is estimated to be:
, square miles
A- = total contour area for the reference sample of airports for a given year
and noise reduction alternative
NK|, v = total equivalent jet aircraft air carrier operations in the nation for the
specified year assumed equal to the total air carrier operations minus
90 percent of the nonjet operations
N_, x = corresponding total equivalent operations for the reference sample airports
" in the specified year
The assumptions upon which this scaling procedure are based may be stated
as follows:
1. The total area within a given noise contour is directly proportional to
the number of equivalent (jet) aircraft operations. Thus, for two airports
with different number of total operations, but otherwise identical, the
total areas within a given contour level at each airport is expected to
vary in direct proportion to the ratio of equivalent operations (evidence
to support this concept is presented in Appendix A).
33
-------
200
-------
2. With one exception, obvious secondary effects on contour area for a
constant number of operations will tend to vary in random fashion over
a representative sample so that variations in the relationship between
contour area and equivalent operations between specific airports will
tend to average out over a large sample, i.e., the population of all
the nation's air carrier airports.
3. The exception to neglecting secondary effects is to lump all air carrier
aircraft into just two types jet and nonjet and to count the noise
impact of the latter by counting 10 nonjet aircraft operations as equiva-
lent to one jet aircraft operation. This highly simplified model for
equivalent operations is considered justifiable for this initial forecast
estimate of national airport noise impact.
For maximum accuracy in defining the 1972 baseline area for the nation, the
larger 23 airport sample is used as the reference sample to define A - and Np, ..
For the years 1987 and 2000, the three airports evaluated in this study are
used as the reference sample for consistency in future years. In general, as illustrated
in Figure 3-6, the correlation between the total contour areas for comparable cases for
the 23 and three airport samples is quite good. However, upon closer examination, it
becomes clear that the total contour area for the three airports (A,,) is correlated better
with the area for 23 airports (A__) for 1987 cases only than for all of the years combined.
Furthermore, it was clear that for the 1972 baseline case, the results for the three air-
ports would not be a reliable model for NEF 30 areas for the 23 airports and thus, similarly
unreliable for extrapolating to the nation. In summary, therefore, the 23 airport data
were used, with the preceding equation, to estimate the national values prior to 1987 and
the results for the three airports in this study were used for the years 1987 and 2000.
In all cases, the specific scaling factors employed are summarized as follows:
35
-------
Table 3-6.
Summary of Scaling Factors Used to Extrapolate
Results to Nation
Year
1972
1978
1981
1987
2000
No. of
Reference
Airports
23
23
23
3
3
Equivalent Jet Operations*
Reference Airports
11,650
13,722
15,007
2,499
3,414
Nation
22,231
26,623
30,205
38,493
54,795
Ratio of
Equivalent Jets (Nation)
Equivalent Jets (Reference Airports)
1.91
1.94
2.01
15.4
16.1
»t« = jpt AJp Corner p!'j? 10 r»?rc'?nt of Pror*e!!<3r Air Corner Ooerotion? P?r Dciv
36
-------
Q>
O
D
O"
to
O
Q.
CO
CM
O
0
o
o
U
"o
"o
CO
CM
1400
1200 -
1000
0 1972
A 1978
o 1981
a 1987
0
Figure 3-6.
25 50 75 100 125 150
A,., Total Contour Area for Three Airports, Square Miles
Relationship Between Total Contour Area for 23 Airports (A«,J and
Three Airports (A_). (For the sake of illustration these simple regression
lines were forced through the origin.) Data from Reference 1 for all
alternatives and NEF values.
37
-------
4. AIRPORT/AIRCRAFT FORECAST ANALYSIS FOR U.S.
The airport operations data base, as indicated earlier, was derived from informa-
1 2
tion from the Wyle/DOT 23 Airport Study, FAA aviation statistics, and a special
3
study, which is contained in this report, conducted by R. Dixon Speas Associates.
The following paragraphs summarize the data and projections from these sources which
were used in this study.
4.1 Forecast of Fleet and Airport Operations
The information in this section, prepared by R. Dixon Speas Associates, contains:
1. A forecast of the general types and numbers of transport aircraft expected
to be in operation in the U.S. air carrier fleet in the year 2000.
2. A forecast of the numbers of daily movements of aircraft of each general
type expected to be operating in the year 2000 at Los Angeles International, St. Louis,
and Dulles Airports.
The U.S. fleet forecast is based on a prediction of continued advances in air-
craft technology, and without significant changes in the nature of air transportation
services provided in response to a forecast of continuous growth and demand.
The airport operations forecasts reflect a prediction of continued existence of
these major hub airports, growth in the average size of air carrier aircraft, and con-
straints on the development of airport capacity relieved by improved operating efficiency
and acceptance rates.*
4.1.1 Long Term Fleet Forecast
The forecast of the future makeup of the aircraft fleet proceeded with the
following steps:
1. Forecast of traffic demand
2. Forecast of capacity required to satisfy demand
*
Thus, for the purpose of this report in developing operational data for the year 2000,
airport capacity was considered to be unconstrained (improvements made to take
care of new loaa's).
38
-------
3. Forecast of future aircraft unit productivity
4. Forecast of required fleet size
5. Forecast of aircraft categories in the fleet
Forecast of Traffic Demand
The traffic forecast used in this analysis was an extension to the year 2000 of
the forecast (through the year 1987) developed by Speas Associates for the Wyle/DOT
Airport Noise Reduction Forecast Study. The new resulting forecasts coincide in the
year 1987 with those in Reference I and reflect conservative estimates of required air
carrier capacity by the year 2000.
Forecast of Capacity Required
The required total fleet capacity, in available ton-miles (ATMs), was computed
using the following load factors:
Scheduled Domestic Passengers 60 Percent
Scheduled International Passengers 60 Percent
Nonscheduled 85 Percent
Cargo 42 Percent
Based on these data, and a gradually decreasing rate of growth, the required
capacity through the year 2000 was estimated to be:
1980 112 billion ATMs
1985 185 bill ion ATMs
1987 218 billion ATMs
1990 278 billion ATMs
1995 385 billion ATMs
2000 500 bill ion ATMs
39
-------
Forecast of Future Aircraft Unit Productivity
Aircraft unit productivity (annual ATMs per aircraft) has increased dramatically
in recent years. In I960, the average aircraft productivity was about 5 million ATMs
per year and by 1970 it was about 18 million, reflecting the period of transition from
propeller aircraft to larger, faster jets.
Unit productivity is forecast to continue to increase, but at a somewhat lower
rate. The increase is mainly attributable to:
- Continued increases in aircraft utilization (hours per aircraft per year)
- Some additional increases in average aircraft speed (due, in fum, to
continued retirement of propeller aircraft in the near term and intro-
duction of SSTs in the long term)
- Increases in aircraft capacity, averaged over rhe fleet, from the present
level of about 20 rons to about 50 tons by the year 2000.
Forecast of Required Fleet Size
The final estimates of the traffic demand and resulting estimates of the total fleet
size, calculated by dividing the total capacity required by the average unit productivity,
are given in the following table.
Table 4-1
Forecast of Traffic Demand and Fleet Size
Year
1980
1985
1987
1990
1995
2000
Revenue
Passenger
Miles
(Billions)
450
730
850
1075
1470
1885
Revenue
Cargo
Ton Miles
(Billions)
17
30
36
47
67
90
Capacity Required
ATMs (Billions)
112
185
219
278
385
500
Average Annual
Unit Productivity
ATMs (Mi II ions)
36.4
45.5
49.8
58
69
77
Fleet
Size
3080
4050
4400
4800
5600
6500
40
-------
The method for applying these estimates of fleet size to the definition of
specific aircraft operations at the three representative airports has been developed
in detail in Reference 1. To summarize for this report, the development of estimated
fleet mixes for each of the study airports involves three primary steps. The first step
involves estimating passenger traffic and total operations at each airport. The second
step required that the projected distribution of the U.S. fleet be converted into a dis-
tribution of operations of the U.S. air carrier fleet. The third step developed airport
mixes based on a comparison of their present air carrier operations mix versus mix for
total U.S. operations, and extrapolated a general relationship into the forecast years.
The average aircraft size estimate for forecast years was utilized in this step as a general
controlling number. Details of the forecast aircraft categories follow.
4.2 Forecast of Aircraft Categories
The major aircraft categories considered for projection of the U.S. fleet are
characterized by five "levels of technology:"
e Level 0 (Zero) Propeller aircraft, both piston- and turbine-powered.
» Level I Turbojet and low bypass ratio turbofan aircraft based upon the
technology of the early 1960's. These are typically "narrow body" aircraft with normal
operating speeds in the Mach .80 to .84 range. Examples are B707, B727, B737, DC-8,
and DC-9. New production of these aircraft beyond 1974, designated in the airport
activity forecast tables in Appendix C as "unspecified," were assumed to be equipped
with quiet nacelles (SAM).
e Level II High bypass ratio turbofan aircraft based upon the technology of
the late I960's. These are the current generation of "wide body" aircraft and their
expected evolutionary developments. Examples are B747, DC-10, L-1011, and A.300B.
41
-------
e Level III Aircraft based on the technology of the later 1970's and
early 1980's. These are assumed to differ from the Level I and II families through
substantial improvements in propulsion/ aerodynamic, and structural efficiency, as
well as advanced noise reduction technology. The changes assumed reflected these
improvements.
a Level IV Supersonic transport aircraft in the Mach 2 to 3 range based
upon conservative evolutionary developments from the technology of the 1970's. (SST
aircraft noise impact was included in this study by assuming noise characteristics were
equivalent to current 4-engine narrow body turbo fan aircraft with SAM retrofit. )
Figure 4-1 indicates the history and forecast of the distribution by category
of the U.S. fleet. The figures show the rapid displacement of the Level 0 (propeller)
aircraft by Level I during the 10 years, 1959 to 1969. The Level II aircraft are pro-
jected to expand their share of the fleet over the 1975 to 1985 period, but this will not
be as dramatic a transition as was the initial changeover to jets because thfi rfilnttve
improvements in vehicle productivity and efficiency of the total air carrier fleet will
not be so great. Beginning in the early 1980's, the retirement of the older Level I jets
with 15 to 20 years of service will lead to the introduction of new technology (Level III)
aircraft of small-medium capacity, and by the late 1980's, large capacity aircraft of
this same general technology level will begin to supplant the large Level II aircraft.
Supersonic transports (Level IV) are forecast to be introduced in the early 1980's, grad-
ually reaching about 450 aircraft by the year 2000.
Table 4-2 summarizes the resulting estimate of the fleet for the year 2000,
indicating the forecast numbers of aircraft by size and range category.
42
-------
7000
u.
O
cc
Ul
CO
5
13
2
6000
5000
4000
3000
2000
1000
TECHNOLOGY LEVEL III
MEDIUM-LARGE
TECHNOLOGY LEVEL II
TECHNOLOGY LEVEL 0
PROPELLER AIRCRAFT
TECHNOLOGY LEVEL III
SMALL-MEDIUM
1950
2000
Jump caused by inclusion of
Alaskan and Supplemental carriers
Figure 4-1. History and Forecast - U.S. Air Carrier Fleet (Reference 3)
43
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Table 4-2
Fleet Forecast Summary Year 2000
Technology
Level
I
II
III
IV
i i
Aircraft
(-. *
Size
Small
Medium
Large
Small
Medium
Large
SST
Seating
Capacity
90 to 200
200 to 300
250 to 400
>400
ICO to 250
250 to 400
>400
150 to 300
Total
Number of
Aircraft
325
400
500
600
1,625
1,300
1,300
450
6,500
Stage Lengths
0 to 2500 miles
0 to 500 miles
0 to 2500 miles
>500 miles
0 to 2500 miles
500 to 2500 miles
500 to >2500 miles
> 2500 miles
i
Small .~2-Engine
Medium ~3-Engine
Large ~4-Engine
44
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4.3 Forecast of Level III Aircraft Characteristics
Based on the projections given in the preceding section, two-thirds of the
U.S. fleet will consist of Level III aircraft in the year 2000. Therefore, it was
necessary to make some assumptions about Level III aircraft noise and performance
characteristics.
4.3.1 Performance Characteristics
Although industry studies have been recently carried out on performance and
noise characteristics of advanced technology aircraft, these studies were not con-
sidered applicable for purposes of this report. Therefore, assuming potential
weight savings due to improved structural design and material selection, and weight
savings due to improved propulsion efficiency and aerodynamic performance, it is
estimated that Level III aircraft should have approximately the same cruise perfor-
mance capability as current wide body aircraft with the same payload and range but
with a lower maximum takeoff weight. To account for the resulting improvement
in aircraft takeoff performance, the climb angles during takeoff for current wide
body (Level II) aircraft were modified to correspond to a reduction in takeoff weight.
The noise reduction due to increased distances to the aircraft (higher takeoff profiles
with larger thrust to weight ratios) or reduced noise output for lower engine thrusts
are assumed to be roughly similar. The final takeoff profile curves selected for the
Level III aircraft are shown in Appendix B.
4.3.2 Aircraft NoiseoCharacteristics
The basic approach for estimating the noise characteristics of Level III aircraft
consisted of four basic steps summarized below.
0 Define a reference noise spectrum for current 3-engine wide body aircraft.
Estimate the decrease in this noise spectrum for Level III aircraft assuming
a "quiet nacelle"-type treatment is incorporated in the latter.
45
-------
Use the modified sound spectrum, along with corrections, for duration
and propagation loss to estimate Effective Perceived Noise Levels versus
slant range for the reference (maximum thrust) condition.
o Empirically correct the levels to other thrust conditions and to 2- and 4-
engine Level III aircraft based on corresponding data for Level II aircraft.
These procedures are outlined in more detail in the following.
o Reference Spectrum Level II Aircraft
The reference spectrum consisted of published one-third octave band sound
levels of a 3-engine wide body aircraft, normalized to a distance of 200 feet, an angle
11 13
of 110 degrees to the engine inlet, a maximum takeoff thrust and standard day conditions.'
The resulting spectrum is shown by the upper solid line in Figure 4-2.
« Reference Spectrum Level III Aircraft
It was assumed that the advanced technology (Level III) aircraft would be
designed with noise suppression for the fan inlet and exit comparable to that achieved
12
by an advanced "quiet nacelle" system that could be employed. Representative values
for the additional attenuation obtainable for this design were estimated in the following
manner.
I. The levels observed for the current 3-engine wide body aircraft (top line
in Figure 4-2) were compared to predicted levels for the same engines without any
nacelle treatment using jet engine noise prediction methods developed by The Boeing
12
Company. This provided a measure of the amount of fan noise reduction achieved
with current technology aircraft.
2. The maximum total attenuation obtainable with a quiet nacelle treatment
12
was then estimated using nacelle attenuation prediction methods in the same reference.
46
-------
120
CM
E
z no
a.
o
CN
O
i_
" 100
V
90
-o
c
80
o
D
CD
(U
I 70
O
c
o
60
50
Current
Technology
Level II
Aircraft
Sea Level, 77°F, 70% Relative Humidity
Takeoff at 200 ft. - 110° re: Inlet
Additional Attenuation
(Level II to Level III)
Fan Inlet(Level II)
Composite for Advanced
Technology (Level III)
Aircraft
III I
100 200 400 1000
Frequency
(Hz)
2000
4000
\
I I
10,000
Figure 4-2. Three-Engine Wide Body Reference Spectra
(Data for Level II Aircraft from References
11, 12, ond 13. Data for Level III Aircraft
Computed see Text)
47
-------
3. The difference between this latter maximum attenuation for advanced tech-
nology aircraft and that predicted from step 1 for current technology aircraft was then
applied as the incremental increase in fan noise reduction anticipated for Level III air-
craft. This approach insured that one consistent industry-developed method was used to
evaluate only the incremental change in fan noise attenuation.
It was also assumed that the jet noise portion of the current engine noise signa-
ture, in Figure 4-2, was attenuated by an additional 3 dB. For reference purposes,
Figure 4-2 shows, in addition to the overall noise level for Level II aircraft, estimated
levels of its major components and, finally, the resulting estimate of the composite
attenuated noise signature for Level III aircraft.
Effective Perceived Noise Level Versus Distance
To obtain values of EPNL versus distance, the new reference spectrum was first
used along with an improved air absorption propagation loss model to compute maxi-
mum Perceived Noise Level (PNLM) versus slant range. EPNL versus slant range was
then cemptied from c.~. empirical correction between CPNLaiiu* PNLm veisu;. slant
range, reported in Reference 12, which was derived from extensive experimental data
on current narrow body jet aircraft. The air absorption propagation loss model actually
employed provides attenuation values nearly the same as those computed from the
industry standard for standard day conditions.
0 Corrections for Varying Thrust and Number of Engines
The EPNL versus slant range values (at maximum takeoff power for a Level III
3-engine aircraft) were extrapolated to lower thrust levels using the same comparable
changes in EPNL noted for Level If aircraft. The 3-engine noise curves were adjusted
for application to the 2-engine Level III aircraft by subtracting 1.8 EPNdB, which
accounts for the difference in the number of engines. For the 4-engine Level III air-
craft, the 3-engine noise curves were increased by 3 EPNdB, which accounts for the
difference in the number of engines and the difference in maximum corrected net thrust.
The resulting final values of EPNL versus slant distance for Level III aircraft are given
in Appendix B.
48
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REFERENCES
1. Barrel, C., Sutherland, L. and Simpson, L, "Airport Noise Reduction Forecast -
Vol. I - Summary Report for 23 Airports, " Rept. No. DOT-TST-75-3, U.S. Dept.
of Transportation, Wyle Laboratories, El Segundo, California and R. Dixon Speas,
Manhasset, L.I., New York, October, 1974.
2. Federal Aviation Administration, "FAA Air Traffic Activity, Fiscal Year and
Calendar Year 1972, " U.S. Department of Transportation, Federal Aviation
Administration, Washington, D.C.
3. Speas, R. Dixon and Associates, "A Long Range Forecast of the U.S. Air Carrier
Fleet and Operations at LAX-STL-IAD in the Year 2000. " R. Dixon Speas
Associates, Manhasset, L.I./ New York, May 13, 1974.
4. Hurlburt, R.L., "Report on Operations Analysis Including Monitoring, Enforce-
ment, Safety and Costs (Aircraft)." Report No. NTID 73.3, U.S. Environmental
Protection Agency, July 1973.
5. Federal Aviation Administration, "Federal Aviation Regulations: Part 36 - Noise
Standards: Aircraft Type Certification," 1969.
6. Federal Aviation Administration, "Federal Aviation Regulations, Part 25 -
Airworthiness Standards: Transport Category Airplanes."
7. Bartel, C., Coughlin, C., Moran, J., and Watkins, L., "Airport Noise Reduction
Forecast Vol. II - NEF Computer Program Description and User's Manual," Rept.
. No. DOT-TST-75-4, U.S. Dept. of Transportation, October 1974.
8. Simat, N. and Carlson, K., "Forecast of Air Traffic Demand and Activity Levels
to the Year 2000. " Report No. PB 216 252, Aviation Advisory Commission,
Washington, D.C. Simat, Helliesen & Eichner, Inc., Washington, D.C., 1972.
9. U.S. Environmental Protection Agency, "Information on Levels of Environmental
Noise Requisite to Protect Public Health and Welfare With an Adequate Margin
of Safety." Report No. 550/9-74-004, March 1974.
10. Personal Communication, H.J. Nozick, U.S. Environmental Protection Agency,
Office of Noise Abatement and Control, June 1974.
11. Lockheed California Company, "Preliminary L-1011/RB.211-22B Flyover Noise
Definition," Report No. LR 26075, Vol. II, Lockheed California Company,
Burbank, California, 1973.
R-l
-------
REFERENCES (Continued)
12. Dunn, R.G., et al., "Jet Engine Noise Source and Noise Footprint Computer
Programs, " NASA Report No. CR 114517, NASA Ames Research Center,
The Boeing Company, Seattle, Washington, 1972.
13. Douglas Aircraft Company, "Determination of Indoor Sound Levels for Jet
Transport Aircraft, " McDonnell Douglas Corporation, Long Beach, California,
29 March 1973.
14. Federal Aviation Administration, "Airports Certificated for Scheduled Air
Carrier Service, " Form 5010-2, June 1, 1974.
15. Society of Automotive Engineers, "Standard Values of Atmospheric Absorption
as a Function of Temperature and Hurridity for Use in Evaluating Airrrrff
Flyover Noise, " ARP 866, August 31, 1964
16. Sutherland, L.C., Piercy, J.E., Bass, H.E., and Evans, L.B., "A Method for
Calculating the Absorption of Sound by the Atmosphere." Paper presented by
Members of the Sl-57 Working Group, Sound Propagation, before 88th Meeting,
Acoustical Society of America, St. Louis, Missouri, November 1974.
17. Federal Aviation Administration, "Terminal Area Forecast, 1975-1985," U.S.
Department of Transportation, Federal Aviation Administration, Office of
Aviation Economics, Aviation Forecast Division, July, 1973.
18. Federal Aviation Administration. Unpublished data, February 12, 1975.
R-2
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APPENDIX A
AIRPORT NOISE IMPACT ANALYSIS
This appendix outlines a procedure for extrapolating estimates of the total
area within NEF 30 or 40 contours to the area within NEF 20 contours. The latter
p
value corresponds approximately to a Day-Night Average Sound Level (L ) of 55.
dn
In addition, a method is defined for estimating the total impacted area which excludes
the portion within the airport boundary and area over water. This method is then applied
to development of a procedure for estimating the total and impacted area for the nation's
air carrier airports. The latter procedure includes the evaluation of the distribution of
air carrier airports, according *o their number of daily operations, for the years 1972,
1987, and 2000. Finally, the detailed tables of computed areas for the three airports
and estimated values for the nation are provided.
A. 1 Extrapolation to NEF 20 Areas
By combining data from a few specific cases for the three airport sample
for which NEF 20 contours were computed with data from the Airport Noise Reduction
Forecast study, it was possible to show the relationship indicated on Figure A-l for
enclosed area relative to the area within the NEF 30 contour. The average relationship
indicated in the figure is equivalent to a doubling of area within NEF contours for each
decrease of NEF by 4.1 dB or, alternately, an increase in area by a factor of dbout 2.33
for each decrease in NEF by 5 dB. On the basis of this scaling law, the areas computed
for NEF 30 were increased by a factor of 5.44 to obtain the estimate for areas within
NEF 20 using the equation shown in Figure A-l.
A.2 Evaluation of Impacted Land Excluding Airport Property and Area
Over Wafer
Drawing, again, on the detailed data from the Airport Noise Reduction
Forecast Study in Reference 1, Figure A-2 shows the systematic relationship obtained
between the sum of the total areas within NEF 30 to 45 contours for the 23 airports
A-l
-------
n 23 Airport Dora (Reference 1)
3 Airport Data (This Report)
30 35 40 45
NEF, dB
Figure A-1. Relative Change in Total Area Within NEF Contours As a Function of NEF Value
A-2
-------
1200
1000
800
cr
IS)
o
£
600
o
e-
400
200
80
#40
°8r
O NEF 30
O NEF 35
0 NEF 40
A NEF 45
40 80 120
X, Sq. Mi.
23
Y ^ I A.jk*
*» I * *
X = I A;jk
[X2 *(88.7)? ]"-83.7
VIM 0,724 (X - 8S 7) fcr X > 300 s~ ~:
(A-l)
200
= tofa' area af
400 600 800 1000
X, Sum of Total Areas, Square Miles
1200
1400
a'T3ort f°r the jth olternative wifhin the kth NEF value contour.
Aijk
= impacted land area at the ith airport for the jth alternative within the kth NEF
value contour.
Figure A-2. Impacted Land Area Versus Total Area for Sums of Areas for Alternatives
and NEF 30-45 Values at 23 Airports (Data from Reference 1)
A-3
-------
and the total impacted area which excludes airport property and area over water.
Note that this figure also includes the effect of various alternatives and time periods
(1972 1987) on the relationship between total and impacted areas. We will examine
this type of relationship in more detail later in this appendix. The linear trend shown
in Figure A-2 for large values of total contour area can be fairly well explained in
terms of a simple model which would predict that for the 23 airports, the impacted
area is 72.4 percent of the total contour area in excess of a fixed minimum (non-
impacted) area of about 89 square miles representing airport property within the con-
tour. The more complex equation shown on the figure (Equation A-l) represents a
hyperbola which fits the nonlinear relationship between total area and impacted area
when the former is less than about 300 square miles (for the 23 airports).
i
A.3 Method for Extrapolation of Study Results to the Nation
The following technique was developed in order to extrapolate the results
of the airport sample considered in this study (23 airports for the 1972 baseline and
3 airports for the years 1987 and 2000) to estimated national values for total and im-
pacted area. The technique involved the following elements to predict the total
contour area.
Estimate the profile of the nation's air carrier airports by number of
air carrier operations for the years 1972, 1987, and 2000.
Estimate the percent of nonjet air carrier operations at each airport
(grouped according to number of operations). Add 10 percent of
these nonjet operations to the jet air carrier operations to obtain the
"equivalent jet" operations.
Estimate the total contour area for each airport category according
to the number of equivalent jet air carrier operations.
Sum up the total contour areas using the previously developed profiles
of airports by numbers of operations.
A-4
-------
To estimate the total impacted land area, the following additional steps
were taken:
9 Estimate the components of nonimpacted area (i.e., airport property
and water area inside the contour). It was found possible to roughly
estimate these nonimpacted area components by knowing the number of
air carrier operations at an airport, and its general proximity to water.
/
« Use the preceding profile of air carrier airports (for 1972) to compute
the total impacted land area for the 1972 baseline case for all of the
nation's airports.
© Use these results to modify results of Section A. 2 which were based on
the 23 airport data, to a form suitable for estimating impacted land area
for all of the nation's airports.
The following considers each of these elements in more detail,
A.3.1 Profile of the Nation's Air Carrier Airports by Number of Operations
The total number of air carrier operations in the U.S. were forecast in
Reference 1 through the year 1987. Based on the additional forecasts on air carrier
activity to the year 2000 discussed in Section 4.1, it was possible to estimate the growth
in air carrier operations to the year 2000 for the U.S. air carrier fleet. Starting from
a figure of 14.3 million operations per year in 1987, it was estimated that annual opera-
tions would grow at the rate of 2.6 percent per year to reach 20 million operations per
*
year by the year 2000. This estimate was consistent with the forecast growth in air
carrier capacity (available ton-miles), unit productivity (available ton-miles per air-
craft), number of air carrier aircraft and the corresponding slow decrease in the average
number of daily operations per aircraft, as the size and trip lengths of the fleet-average
The forecast of total operations at the three sample airports in this study increased
at a rate equivalent to 2.4 percent per year from 1987 to 2000. For the purpose of
this report in developing operational data for the year 2000, airport capacity was
considered to be unconstrained (improvements made to take care of new loads).
A-5
-------
aircraft tend to increase. Several variations on this empirical extrapolation of oper-
ations to the year 2000 produced similar results so that a more detailed analysis was
not considered warranted.
The forecast trends in these parameters are shown in Figure A-3. The values
from 1987 on, including some previously listed in Section 4.1, are summarized as
follows. (Values for these parameters before 1987 may be computed or obtained from
the data in Reference 1.)
Year
1987
1990
1995
2000
Annual
Operations
x 106
14.3
15.4
17.6
20.0
Average
Daily Operations
Per Aircraft
8.9
8.8
8.6
8.4
ATM
(Annual Jotal)
x 10'
219
278
385
500
U.S.
Fleet
Size
4400
4800
5600
6500
With the knowledge of total operations, it was now possible to estimate the profile of
operations per airport using an extrapolation of airport operations forecast data from
Reference 17. The latter provides values of actual (FY 1973) and forecast (FY 1985)
operations at each of the air carrier airports in the U. S. This includes all airports
with FAA control towers plus a large number of smaller airports without FAA control
towers. The estimated cumulative distribution of these airports by number of opera-
tions per day in the study years 1972, 1987, and 2000 is shown in Figure A-4. The
cumulative distribution is shown in terms of number of operations in logarithmically-
spaced intervals for which the geometric center points differ by 10 to the 0.1 power.
The estimated distributions for the years 1972, 1987, and 2000 were constructed
as follows. For 1972, the profile of operations for the 23 airports were used along with
values from Reference 2 for the other larger airports (32 or more operations per day). The
A-6
-------
80
.60
40
Forecost Based on Reference 1
Forecast Based on Reference 3
o
E
D
L.
D
a.
O
6
V
o
U
CO
Z)
20
10
8
No. of Air Carrier
Aircraft
x 102
Available Ton Miles
Per Year
x 109
6
Annual Operations x 10
Doily Operations/Aircraft
2
1.5
1970
Figure A-3.
Unit Productivity ,
(ATM Per Aircraft) x 10
1980
1990
2000
Year
Forecast of Size and Activity of U.S. Air Carrier Fleet
A-7
-------
x
o
O
v>
-------
operations for smaller airports were estimated by adjusting the F' ' 1973 distribution until
the total integrated number of operations at all the airports agreed with the value of
10.02 million operations per year cited in Reference 1 for CY 1972. The adjustment
was a minor one and was only made to provide a consistent profile of operations for the
1972 baseline.
For the years 1987 and 2000, the FY 1985 profile of airports in Figure A-4
was adjusted by shifting the curve horizontally along the percent axis. The shift was
just that necessary to change the mode of the distribution (i.e., the 50 percent point)
by the same ratio as the ratio of total operations forecast in Reference 17 for FY 1985
and the desired total operations for 1987 or 2000. This empirical approach provided
a new distribution which, within 1 to 2 percent, added up to the desired number of
total operations. No further adjustment was made to try to eliminate the remaining
small residual error in total number of operations. Furthermore, no attempt was made
to include the addition of new, very small, air carrier airports in this distribution which
could occur as new cities are formed. However, it should be noted that the forecast
distribution of airports for future years show a steadily increasing number with more than
10 air carrier operations per day, (i.e., 292 airports in 1972, 319 In 1987, and 365 in
the year 2000). This is considered to represent the increase in airports with sufficient
operations to cause a significant noise impact. As shown later on, it was estimated
that, for the 1972 baseline case, less than 10 air carrier operations per day did not show
any significant noise impact. This is due, in part, to the estimated higher proportion
of low-noise prop aircraft at such small airports. In future years, as prop aircraft are
replaced with jets, the decreasing noise levels of these newer jets will tend to minimize
any significant increase in noise impact for such low levels of operations. Thus, while
there will undoubtedly be an increase in the total number of air carrier airports in the
future, the increase, over and above the number accounted for in the projections in
Figure A-4, is expected to occur in categories of very low operations per day below the
level of significant impact. When specific operations data had to be estimated (i.e.,
small airports for 1972 and all airports for 1987 and 2000), the total operations were com-
puted by the sum of the number (n.) of airports in a given (i ) category of operations per
day multiplied by the geometric mean (N.) of the operations per day in each i category.
A-9
-------
Thus, the total for all airports was simply
I
S~*
N =/ * N. n. , operations (A-2)
i=1
where the index I represents the number of categories
A. 3. 2 Nonjet (Propeller) Aircraft Operations
Based on an analysis of the 1972, 23 airport sample and 1972 aircraft
traffic data for a 10 percent sample of the smaller airports, an estimate of the relative
number of jet aircraft operations was made as a function of number of daily departures
for each interval in the airport distribution. As shown in Figure A-5, the estimate for
1972 ranged from 6 percent nonjet operations at the large airports with a smooth tran-
sition to 100 percent nonjet operations at airports with less than two operations per day.
For 1987, the estimated shift in percent distribution of propeller aircraft was made so
that the decrease in total number of propeller operations predicted, according to the
forecast profile of total operations, corresponded approximately to the values projected
in Reference 1 for total operations of propeller aircraft (i.e., 0.3x 10 operations per
day in 1987). There were no propeller aircraft operations forecast by the year 2000
(see Section 4.2).
The nonjet operations were counted. for this study, at 10 percent of their
actual value and added to the actual jet operations to provide the total equivalent jet
operations as a conservative basis for estimating impact from all air carrier aircraft.
A . 3 . 3 Total Area Within NEF 30 Contours Versus Equivalent Jet Operations
Using the 23 airport data from Reference 1, a regression line between total
area within the NEF 30 contours (for 1972 baseline conditions) and total (equivalent)
jet operations for 1972 was constructed. A correlation coefficient (r) of 0.839 was
obtained when the logarithm of total contour area (A ) was plotted versus the log of
total equivalent operations (N ) to produce a regression equation given by:
A, =0.097 (N ) lt012 (A-3)
A-10
-------
100
o
u
g. 80
8-
O
c 60
§
£ 40
i r
T I
20
Estimated Trend - 1972
O - Uata from 10 percent
Sample of All Air Carrier
Airports
Estimated
Trend
1987
10 100
Annual Average Daily Operations
1000
Figure A-5. Estimated Percent of Airport Operations Carried Out
by Propeller Aircraft
A-H
-------
However, as shown in Figure A-6, a simpler expression can be used which is based on
a forced linear fit of the data. This linear expression, which also assumes zero con-
tour area for zero operations, is given by:
A =0.114 N (A-4)
t eq
Such a linear scaling law simply expresses the concept that total contour area would
vary directly with number of equivalent jet operations. The proportionality constant
would, of course, depend on the contour level and aircraft mix or noise reduction
alternative. This general trend towards a simple linear scaling law was observed for
other NEF levels and alternatives.
However, for estimating the total contour area for other cases, for the nation,
it is not necessary to define the particular proportionality constant involved for each
case. Rather the simple linear scaling law defined earlier in Section 3.2 of the main
body of the text can be used. This linear scaling of total contour area by the ratio of
6(jUiVuicut jet opcTotions tciiCvVS imrne~-T/
cited above.
A.3.4 Projected Total Contour Area for the Nation
Applying the techniques defined in the preceding paragraphs, including
the analysis of the airport/operations profiles, the percent nonjet operations, plus air-
port operating data for this study in Reference 1, produced the following figures for
total and equivalent jet operations for the nation and the two airport samples for the
study years.
A-12
-------
400
1 I
2 100
-------
Total Operations Total Equivalent Jet
Per Day Operations Per Day
Year (Nation) Nation 23 A/P 3 A/P
1972 27,452 22,231 11,650 1605
1987 39,233 38,493 17,571 2499
2000 54,795 54,795 - 3414
These values of equivalent jet operations were used, as specified in Section
A.3.3, to predict the national contour areas.
For the 1972 baseline case, the total sample areas employed from the 23
airport study were as follows:
NEF 30 1333 square miles
NEF 40 226 square miles
the total sample areas from the three airports used in this study are sum-
marized in Section A.4 of this appendix along with the areas scaled to the nation.
A.3.5 Impacted Area for the Nation
Evaluation of the components of nonimpacted land area obtained from the
results of Reference 1 made it possible to define the following approximate predic-
tions for (a) the portion of airport property inside a contour in terms of total airport
property (A ) and total contour area (A ), and (b) the portion of contour area over
water (A ) for airports near water.
A-U
-------
Airport Area - FAA Form 5010-2 records as of June 1, 1974 indicate
981 square miles of property area for 463 certificated airports. These national figures
and the specific property areas for 36 major U.S. airports with a total area of 201
square miles provided the basis for the following rough estimates for total property areas
within any of the nation's airports in terms of total operations per day (N. ).
N £ ISO/day, A = 0.2+0.0086 Nf, mi.2 (A-5)
N < 180/day, A =1.8 mi. (A-6)
These relationships are based on a rough approximation of the airport property area versus
operations data shown in Figure A-7.
Impacted Area for Airports Not Near Water - For all of the airports in
the 23 airport sample, when the area over water (Aw) was added (where applicable)
to the impacted land area (A.), it was found that this sum (equal to the total contour
area minus only the airport area within the contour) could be predicted for the total
of the 23 airports, or the total of the 7 smallest of these 23, by the following expression
7?
(At)2l -0.8Ap ,mi.2 (A-7)
As shown in Figure A-8, the curvilinear relationship obtained for small values of the
total contour area (A ) is well defined by Equation (A-7) for either the entire sample
of 23 or the 7 smallest airports. Thus, this equation provided a good estimate of
impacted land area for any airport not near water (those for which A was zero) and
was applied to the detailed national estimate of impacted land area for the 1972 baseline.
Impacted Area for Airports Near Water - Based, again, on the 23 airport
data for airports near water, it was possible to roughly predict the area over water (A )
in terms of the total contour area, A . The following simple relationships, which
depended on airport size, are shown in Figure A-9.
A-15
-------
v>
V
£
o
cr
CO
o
V
x
0)
r
o.
4_
o
Q.
<
29
28
16
14
12
10
2
0
ADallas-Ft. Worth
OIAD
Prediction Line,
=0.2+ .0086 N. , Sq Mi
t
<180, A = I.SSqMi
ORD
O "23 Airports"
Other Major
Airports
Minimum Area = 1 .8 Sq Mi
Based on Remaining 780 Sq Mi
for 463-36 = 427 Airports Not
Identified on This Plot. These
36 Have a Total Area of 201
SqMi.
0 400 800 1200 1600 2000
N , Average Air Carrier Operations Per Day (CY 1972)
Figure A-7. Airport Area Versus Average Daily Operations for
36 Major U.S. Air Carrier Airports
A-16
-------
1600
o
0)
o
o
o_
E
Total Airport Property
Area = 107 Square Miles
1
o
o
o
4-
0 200 400 600 800 1000 1200 1400
A , Total Contour Area, Square Miles
160
120
E p> 80
40
Figure A-8.
b) 7 Smallest Airports
A. + A = [(0.8A ) +A 1 -
i w L P t J
A =29.0 Square Miles
P
0.8A
25 50 75 100 125
A , Total Contour Area, Square Miles
150
175
Total Impacted Land Area Plus Water Area Versus Total Contour Area
for All and Seven Smallest of 23 Airports. (Data from Reference 1)
A-17
-------
£
0)
o
T
to
K
L.
o
"o
O
D
0)
400
300
200
100
0
a) "Large" Airports
N > 300 Ops/Day
0
Cluster of Data Points
for NEF = 40, 45
200 400 600 800
A Total Area Within Contour, Square Miles
900
b) "Small" Airports
N < 300 Ops/Day
? o
20 40 60
A , Total Area Within Contour, Square Miles
Figure A-9. Estimated Area Over Water Predicted from Results of 23 Airport Study
(Reference 1)
A-18
-------
For N > 300 operations/day, A = 0.41 A, square miles (A-8)
For N < 300 operations/day, A = 0.14 A, square miles (A-9)
w
From a rough sampling of about 250 of the air carrier airports, it was estimated that
about 21 percent are located near water with part of the contour areas lying over water.
This proportion was applied later, along with Equations A-8 and A-9, in making the
detailed estimates of impacted area.
Estimate of Total Impacted Land Area for 1972 Baseline - The preceding
techniques have been used to make a detailed estimate of the impacted land area for
the nation for the 1972 baseline case. It was anticipated that a simplified method
could be developed from this analysis which would be patterned after the simple approach
for estimating impacted land area discussed earlier in Section A.2.
The profile of airports by operations for 1972 and the resulting analysis of
the total contour area and impacted land area for the nation for NEF 30 is presented in
TuLJe A-l. Ab inu'ieureu, ihe known results for the 23 airports from Reference i are not
included in the analysis. Thus, only the remaining 491 oir carrier airports (514-23)
were analyzed for this base case. The resulting estimate of total contour area for the
nation wi,thin NEF 30, including the 23 airports, is 2589 square miles just 2 percent
higher than the value obtained by scaling the total contour area for 23 airports to the
nation according to the ratio of equivalent jet operations. The total impacted land
area for the nation was computed to be 1854square miles.
The same result for impacted land area could be obtained by adjusting
Equation A-l shown in Figure A-2 which related total contour area and impacted land
area for all of the 23 airport study cases from 1972 to 1987. First, an adjustment was
made to increase the constant term (88.7) in this expression by the ratio of total opera-
tions for the nation to the total operations for the 23 airport sample. For the years 1972
to 1987, this ratio averaged 2.12 ±0.08. The logic of this adjustment is that, as illus-
trated earlier, airport property scales roughly as the number of operations and this
A-19
-------
Table A-l
Analysis of Total and Impacted Ansa Within NEF 30 for 1972 Baseline at
Air Carrier Airports Excluding the 23 in Reference 1
i
ro
o
A
1 c
Operafion!/t)oy
Minimum
1250
tooo
800
633
500
«00
315
250
2M
160
125
100
eo
A3
SO
40
31.5
25
20
16
115
10
B
SfaKtmum
1600
1250
1000
800
630
500
4 00
315
250
200
160
125
100
80
63
50
40
31.5
25
20
16
12.5
10
Geometric
Mson
1410
1120
890
710
560
445
355
280
225
180
UO
no
89
71
54
45
35
23
22
18
14
II
9
<10
To'ol
0
E
Distribution
of Atiporrs
No
Water
-
-
-
1
1
.
1
3
3
4
5
7
12
9
16
9
20
21
13
13
21
23
15
190
387
Neor
Water
-
-
-
-
-
1
-
2
1
1
4
3
2
2
4
1
8
8
3
1
3
6
3
51
104
F
G
Totol
Operation!
No
Water
-
-
-
723.
560
-
360
821
693
677
706
823
1039
638
674
392
704
604
284
207
291
264
141
351
Near
Woter
-
-
-
-
-
463
-
583
23?
17.1
59?
322
180
132
~234~
4!)
27.'
220
77
2V
49
65
25
94
H
Propeller
Aircrofi
Operations
in percent
6.2
6.5
6.7
7.0
7.5
8.0
9.5
II. 0
13.0
15.0
17.5
20.0
24.0
27.5
32.0
33.0
45.0
52.0
61.5
69.5
77.0
83.5
89.5
95.0
1
Total
Propel!
Aircra
Opcroli
ft
onl
-
-
-
5
42
4
34
154
121
128
228
229
293
212
355
167
441
430
222
164
262
275
149
423
J
K
Equivalent
Jel
Of notion!
Ml.
Wo' '.1
-
.
'
713
522
329
740
6U
5C1
595
675
815
4C3
622
253
41?
322
127
73
8>
6S
27
51
Neor
Water
-
-
-
-
-
480
-
525
211
151
. 505
264
141
99
167
32
165
117
34
11
15
16
5
14
I
M
Total Contour Ar to
No Water
Sq. Ml.
-
-
-
81.9
59.5
-
37.5
84.4
69.8
66.8
67.8
77.0
92.9
54.7
70.9
29.4
47. B
36.7
14.5
8.9
10.1
7.5
3.1
5.8
919.3-
Neor Woter
Sq. Ml.
-
-
N
Airport
Area
Per
Airpofl
12.3
9.8
1 7.9
-
-
54.7
-
5?.?
24.1
17.2
S7./.
30.1
16.1
11.3
19.0
3.t
18.3
13.3
3.f
1.3
6.3
5.0
4.0
3.3
2.6
2.1
1.7
1.8
1.8
1.6
1.8
1.8
1.8
1.8
1.8
1.8
1.8
1.7 i 1.8
1.5 i 1.8
0.6
1.6
336. 4«
1.8
1.8
0
P
Total Airport
Area
No
Water
-
-
-
6.3
5.0
.
3.3
7.8
6.4
7.0
9.0
12.6
21.6
16.2
28.8
16.2
36.0
37.8
23.4
23.4
37.8
41.4
27.0
342.0
Near
Water
-
-
-
-
-
4.0
-
5.2
2.1
1.7
7.2
5.4
3.6
3.6
7.2
1.8
14.4
14.4
5.4
1.8
5.4
10.3
5.4
91.8
0
Impacted
Area
No
Water
-
-
-
77.0
55.6
.
35.0
It
Wolif
Area
-
-
-
-
-
22.4
-
78.3 8.4
64.8
61.4
61.0
67.5
77.2
43.3
51.5
19.2
27.0
17.3
4.9
2.0
1.7
0.8
0.3
0.1
3.4
2.4
8.1
4.2
2.3
1.6
2.7
0.5
2.4
1.9
0.5
0.2
0.2
0.3
O.I
0.2
S
Impacted
Area
Neor
V/a>«
-
-
-
-
-
29.2
.
47.4
19.0
13.5
44.0
21.9
11.2
7.2
11.5
2.0
7.9
4.2
0.9
0.3
0.1
0.0
0.0
0.0
T
Tolol
Impacted
*reo
-
-
-
77.0
55.4
29.2
35.0
IJ5.7
£3.9
74.9
155.0
8?.4
63. 4
50.5
c3.0
21.2
34.9
21.5
5.9
2.3
1.7
0.8
0.2
O.I
966.2*
Kov to Table A-l
Column
A
B
C
O.I
f.G
H
1
J
K
Description
Minimum number of opsro'iorii per d
Geometric mean of daily operation!
Include! airport! without FAA towen
Include* oirport! without FAA towen
Set Column C and Figure A-5.
(F G) H/IOO
F (1 - 0.' H) | Equivalent to lubtroc
G(1-0.9H)| operations and oddin
oy.
°y- ,
(- VAB>.
.
ting ol! propeller
)-back 19 percent.
Co umn
L.M
N
O
P
Q
II
S
T
Det« ription
See Equation A-4. ^
See Figure A--7, Eqi.-otifmi A-5, -d O'.d Column C. E«c udot correipo^dinj
Co umn 0 lime! Column N. Areat for 23 Airporii
Co umn E time! Column N. In Reference 1
See Equation A-7, fllia AW='X Ap = Column O
ond A, = Column L.
See F'njure A-?, Equoticm A- 3, -9 ond Column! M ondC.
See Equation A-7, olio AW = 'Joiumn R, Ap "Column P
ond A. = Column M.
Co umn O plui Column 1
-------
constant (88.7) can be taken to represent the total airport area inside the contours for
only the 23 airports. The second adjustment was to increase the first constant (0.724)
in Equation (A-l) to 0.77 so that the resulting final expression produced the same
estimate of impacted land area (1854) as was obtained from the more detailed analysis
in Table A-l. The logic for this minor correction is that the smaller airports are expected
to have less contour area lying over water so that the net impacted area would tend to be
greater. The resulting final expression for estimating impacted area (A.) in terms of total
contour area (A ) for all the nation's airports is
( r 2 2\2 )
A. =0.77 j A +(188) -188 > , square mile* (A-10)
Since this type of relationship proved valid for the 23 airports, it was considered valid
as a predictor for the national estimates of impacted land in this study.
A A c ------ , -f t> i
- -
The values for total and impacted land area for the nation are given in
Table A-2 for NEF 20, 30, and 40. They were computed with the procedures specified
in the preceding sections of this appendix.
Table A-3 contains the raw data on total area within the NEF 30 and
40 contours for each airport and primary noise reduction scenarios. Table A-4 contains
the raw data and corresponding national estimates for the secondary alternatives evaluated
for 1987 only.
A-21
-------
Table A-2
Estimated Total Area (National) and Impact Area (National) for Noise Abatement Alternatives for 1972, 1987 and 2000
(Area in Square Miles and Rounded to Two Significant Digits)
i
to
N3
Year
1972
1987
2000
Operational Procedures
Approach
3°
X
X
X
X
X
6°/3°
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Takeoff
Cutback
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Acoustic Linings
SAM
30
X
X
X
X
X
X
X
X
80
X
X
X
X
737/727-100
X
X
Refanned Engines
REFAN
727-200/DC-9
X
X
80
X
X
Aircraft Noise Level
FAR 36
-5
<
X
-10
X
X
-15
X*'
X
-20
X"
X
NEF
20
Total [Impact
14000
10000
8500
9600
7700
5800
4100
3800
3000
1600
700
290
4300
4300
4000
3600
3600
3500
3400
3000
2500
1200
560
1000
7600
6400
7200
5800
4300
3000
2300
2200
1100
410
120
3200
3200
2900
2600
2600
2600
2500
2200
1800
790
310
NEF
30
Total
2500
1900
1600
1800
1400
1100
760
700
550
290
130
54
790
790
740
670
670
630
630
540
460
230
100
impact
1800
1300
1100
1200
940
710
460
410
300
120
31
6
480
480
440
390
390
360
360
300
240
84
19
NEF
40
Total jiTpocf
430
340
270
330
300
240
180
160
120
54
25
11
160
160
160
160
1*0
150
150
130
100
47
22
220
150
110
150
130
90
56
45
27
6
1
0
45
45
45
45
45
40
40
31
19
4
1
*Estina'ed impacted area excluding airport boundary and area ovur water, using Equation 10.
**These cases were computed but were not assumed to be achievab'e by 1987 (see text - page 1
1).
-------
Table A-3
Summary of Raw Data Showing Total Area Within NEF 30 and 40 Contours at Each Airport
(Area in Square Miles)
i
to
CO
Year
1972
1987
2000
Operational Procedures
Approach
3° k°/3°
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Takeoff
Cv'bl-.'r.
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Acoustic Linings
SAM
30
X
X
X
X
X
X
X
X
?r>
X
X
X
X
737/727-100
X
X
Refanned Engines
REFAN
727-200/DC-9 ^80
X
X
X
X
Aircraft Noise Leve
FAR 36
-5
X
X
-10
X
X
-IS
I
1
X
X
1
-20
1
X
X.
LAX
Area-sq.rri.
NEF
30
97.2
45.4
37.4
42.2
40.6
27.0
22.2
21.5
17.0
8.7
4.0
1.7
25.8
25.8
23.8
20.9
20.9
20.2
20. 1
17.2
14.2
6.8
3.1
40
20.5
9.6
7.3
9.2
8.3
6.3
5.4
5.2
3.8
1.8
0.9
0.4
5.0
5.0
4.9
4.8
4.8
4.6
4.6
3.7
3.0
1.4
0.6
STL
Areo-sq.mi .
NEF
30
29.9
29.8
28.1
26.8
22.8
21.5
15.6
14.4
10.9
5.5
2.6
1.2
11.7
11.7
11.2
!0.4
10.4
9.0
8.7
8.1
6.9
3.5
1.6
^0
5.4
5.3
5.0
5.1
4.8
4.5
3.4
3.1
2.4
1.1
0.5
0.2
2.5
2.5
2.5
2.5
2.5
2.2
2.2
2.0
1.6
0.7
0.4
IAD
Areo-sq.rri .
NEF
30
24.2
46.7
35.8
43.2
29. 1'
20.6
11.4
9.5
7.7
4.4
1.8
0.6
11.3
11.3
10.7
10.3
10.3
10.2
10.2
8.5
7.2
3.7
1.7
40
4.6
7.5
5.4
7.2
6.7
5.1
2.6
2.1
1.3
0.6
0.2
0.1
2.5
2.5
?.5
2.5
2.5
2.5
2.5
2.1
1.8
0.6
0.4
-------
Table A-4
***
Results of Secondary Alternatives for 1987
(in square miles and rounded to 2 significant digits)
Alternative
Fleet - 10%
Fleet + 10%
N.B. - 50% *
N.B. +50%
N.B. Daytime**
No Night
Flights
Total Area Inside Contours
LAX
NEF30
39.4
44.9
32.4
52.3
28.2
19.7
NEF40
8.6
9.8
7.1
11.1
5.9
3.8
STL
NEF30
26.5
31.1
22.6
34. 9
21.7
12.3
NEF40
4.7
5.4
4.2
5.9
3.9
2.4
IAD
NEF30
40.0
46.9
28.3
57.9
14.3
14.2
NEF40
6.8
7.7
6.0
11.1
3.1
3.1
National Total
Area
NEF30
1600
1900
1300
2?00
1000
710
NEF40
310
350
270
430
200
140
National Impact
Area
NEF30
1100
1300
840
1600
620
410
NEF40
130
160
100
?in
65
37
* N.B. denotes narrow body iets.
** Daytime = 0700 to 2200 hours.
***,The reference for the alternatives is baseline aircraft, 6°/3° glideslope for approach and standard takeoff procedures.
A-24
-------
APPENDIX B
DETAILED NOISE AND PERFORMANCE CHARACTERISTICS
OF ADVANCED TECHNOLOGY (LEVEL III) AIRCRAFT
UTILIZED FOR THIS STUDY
The assumptions for estimating the noise and performance characteristics of
the Level III aircraft were discussed in Section 4.3 of this report. This appendix provides
the specific noise versus slant range and takeoff profile curves utilized in the NEF
computer program for these aircraft. The corresponding data for the current technology
Level I and Level II aircraft are contained in Reference 1.
Figures B-1 through B-3 show the noise (Effective Perceived Noise Level in
EPNdB) versus slant distance curves for the 2-, 3-, and 4-engine advanced technology
aircraft respectively. Each graph shows the predicted noise level at several corrected
net thrust levels and includes, for comparison, the corresponding curve for the Level II
(current wide body) aircraft for one comparable corrected net thrust condition only.
Note that the maximum values of corrected net thrust shown on the graphs
(thrust/6) do not correspond to the maximum static thrust values normally associated
with the aircraft engines. Net thrust is a function of static thrust and velocity of the
aircraft. At takeoff, conditions and velocity less than 250 knots, net thrust decreases
very rapidly with increasing velocity. For example, a typical wide body aircraft engine
has a static thrust of 40,000 pounds/engine at zero velocity and 100 percent rpm cor-
rected to normal atmospheric conditions, while the same aircraft after brake release
at 32 knots and 98 percent rpm has a net thrust of 35,300 pounds/engine; further, at
rotation, 176 knots and 98 percent rpm, the net thrust equals 31,000 pounds/engine.
In most cases, the noise curves in the program for each of the existing aircraft
were calculated by the aircraft manufacturer from actual flyover measurements. These
test measurements were performed while the aircraft velocity was 140 to 200 knots.
Noise curves were constructed by the manufacturer from these data on the basis of
corrected net thrust and normalized to 160 knots. Noise levels at other thrusts were
B-1
-------
obtained by linear interpolation/extrapolation of corrected net thrusts. Note that
the noise curves for the Level III aircraft were computed from one analytical model,
outlined in Section 4.3.2. which is based, in part, on measured data from a 3-engine
(Level II) wide body aircraft.
Figures B-4 through B-6 show the corresponding takeoff profiles for the
advanced technology aircraft.
B-2
-------
CD
I
CO
CQ
o
Z
a.
LU
a>
6
Z
V
o
-------
120
oo
CQ
~a
Z
a.
LU
a>
0)
v>
'o
Z
-o
u
0)
a.
u
a>
no _
100
90
80
70
60
50
30800
24000
19800
I 12200
Thrust (Ibs/eng)
^^ ^
6
100
200
Level II Technology Aircraft
30800 Ibs/eng
400 600 1000
Slant Range - Ft.
2000
4000
6000
10,000
Figure B-2. Noise Curves for Level III Technology - 3 Engine Aircraft.
-------
CD
Oi
CO
-o
Z
Q_
LJU
O
V
0)
i/»
'o
Z
-o
0)
'to
u
>
tJ
120
no
100
90
80
70
60
50
Thrust (Ibs/eng)
6 33600
~ 26900
21100
12300
9900
_ 8000
Level II Technology Aircraft
33600 Ibs/eng
I
100
200
400 600 1000
Slant Range - Ft.
2000
4000
6000 10,000
Figure B-3. Noise Curve!; for Level III Technology - 4 Engine Aircraft.
-------
10
8
0)
o
o
o
.5?
*
0
Takeoff Weight, Ibs
250,000
(Short Range)
260,000
(Medium Range)
I
20 40 60
Distance from Brake Release, 1000 Feet
80
Figure B-4. Takeoff Profiles for Level III Technology, 2-Engine Aircraft
B-6
-------
10 -
Takeoff Weight, Ibs
0
20 40 60
Distance from Brake Release, 1000 Feet
Figure B-5. Takeoff Profiles for Level III Technology, 3-Engine Aircraft
B-7
-------
10
8
W
O z
LL. O
o
O
o
0
Takeoff Weight, Ibs.
550,000
(Short Range)
600,000
M_J:
IVICUI Ulll
0
20 40 60
Distance from Brake Release, 1000 Feet
80
Figure B-6. Takeoff Profiles for Level III Technology, 4-Engine Aircraft
B-8
-------
APPENDIX C
AIRPORT ACTIVITY DATA
The airport- operations data for Los Angeles International, St. Louis, and Dulles
Airports are given in Tables C-l, C-2, and C-2 respectively. Part (a) of each table
are actual figures with total operations based on FAA records for calendar year 1972,
while parts (b) and (c) provide forecast activity data for 1987 and 2000 respectively.
New technology (Level III) aircraft introduced before 1987 are included in
the 1987 operations forecast as unspecified (unspec.) Level I category aircraft. Noise
characteristics for iiiese new aircraft are assumed equal to that for their corresponding
current technology aircraft treated with quiet nacelles so as to nor exceed FAR 36 limits.
C-l
-------
Table C-la
Airport Activity
Los Angeles- 1972
Aircraft
Type*
720B
707-320B/C
707- 120B
DC-8-30
DC- 9- 15
DC-8-55 ,
DC-8-61(-63)
DC-9-32
DC- 10- 10
L-1011
VC-10
707-120/-320
727-200
720
727-100
737-100/-200
747-100
CV880
Turboprop
(STOL)
Arrivals
Day/Night"
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
31
3
16
3
39
11
5
1
10
0
31
14
12
10
10
1
16
2
2
0
1
0
10
8
97
7
8
2
42
13
46
5
34
6
1
0
12
0
Departures by Stage Distance (Statute Miles)
0
500
9
1
5
0
9
2
0
0
2
0
12
5
4
0
9
1
1
0
0
0
0
0
4
1
68
5
4
2
15
4
41
4
3
0
0
0
12
0
500
1000
7
1
1
0
1
0
0
0
8
0
1
0
0
2
1
0
3
1
0
0
0
0
0
0
11
1
4
0
5
2
5
1
0
0
0
0
1000
1500
5
0
0
1
5
0
2
1
1
0
1
1
2
0
0
0
0
0
0
0
15
1
6
1
2
1
0
0
1500
2500
8
1
8
0
22
9
3
0
15
8
4
5
9
1
2
0
1
0
0
7
3
0
16
6
18
2
1
0
2500
3500
2
0
2
2
2
0
2
1
0
2
1
0
2
0
9
3
3500
4500
1
0
1
0
2
0
4500
5500
0
0
1
0
Over
5500
2
0
2
0
* Excludes General Aviation and Military Operations.
** Day: 7:00 AM - 10:00 PM
Night: 10:01 PM - 6:59 AM
C-2
-------
Table C-lb
Airport Activity Forecast
Los Angeles- 1987
Aircraft
Type*
I
I
I
I
II Small
II Medium
II Medium
II Large
Range .
Capability Model
Short-Medium <
Medium
737
DC-9
Unspec.
1727-100
727-200
STOL Unspec.
Medium-Long <
707
DC-8
Uriipcc.
Short-Medium Unspec.
|
Medium
Long j
DC- 10
L-1011
Unspec .
IDC- 10
Unspec.
Medium-Long 747
***
Day
Night
D
N
D
N
D
N,
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
Arrivals
23
3
19
2
21
1
10
3
81
6
35
1
7
6
11
3
16
3
89
19
15
2
16
3
51
8
3
1
69
18
83
17
Departures by Stage Distance (Statute Miles)
0
500
21
2
17
2
18
1
4
1
57
4
30
1
3
1
5
1
2
0
57
8
1
0
1
0
13
0
1
0
9
2
8
0
500
1000
2
1
2
0
3
0
1
1
9
1
5
0
0
0
0
0
0
0
9
5
3
1
3
2
0
0
0
0
8
5
4
4
1000
1500
1
0
13
1
0
0
0
0
0
0
6
1
2
0
2
0
6
0
1
0
8
0
6
1
1500
2500
4
1
2
0
0
5
6
2
i2
3
17
5
8
1
9
1
32
8
1
1
39
11
43
3
2500
3500
1
0
2
0
1
0
1
0
5
0
20
9
3500
4500
1
0
2
0
4500
5500
0
0
Over
5500
'
2
0
* Excludes General Aviation and Military Operations.
** Models indicated as "Unspecified" may include current aircraft and/or new aircraft not yet in production.
*** Day: 7:00 AM- 10:00 PM
Night: 10:01 PM - 6:59 AM
C-3
-------
Table C-lc
Airport- Activity Forecast
Los Angeles -2000
Aircraft Type*
I Unspecified
(737/DC-9
Type
with SAM)
I Unspecified
(727 Type
with
SAM)
I Unspecified
(707/DC-8
Type
with SAM)
pv **
Day
Night
D
N
D
N
D
N
Arrivals
4
1
7
2
27
5
Departures by Stage Distance (Statute Miles)
0
500
3
1
5
2
11
3
500
1000
1
0
2
0
3
1
1000
1500
2
0
1500
2500
11
1
2500
3500
3500
4500
4500
5500
Over
5500
II Small
II Medium
II Large
III Small
III Medium
III Large
IVSST
D
N
D
N
D
N
D
N
D
N
D
N
D
N
47
9
58
11
70
13
190
35
173
32
173
32
11
0
38
5
4
4
0
0
75
19
12
11
17
0
0
0
9
4
11
1
7
0
115
16
33
3
10
0
0
0
7
2
4
1
21
6
75
2
0
0
36
4
36
5
107
12
49
11
6
0
20
6
7
14
0
0
3
1
10
3
0
0
5
2
0
0
5
0
Excludes General Aviation and Military Operations.
*Da": 7:00 AM - 10:00 PM.
Night: 10:01 PM -6:59 AM.
C-4
-------
Table C-2a
Airport Activity
St. Louis - 1972
Aircraft
Type*
707-320B/C
707-120B
DC- 9- 15
DC-9-32
L-1011
707-120/-320
727-200
727-100
737-100/-200
CV-880
BAG- 1 1 1
Turboprop
(STOL)
Arrivals
Day/Nighr
D
N
D
N
D
N
P.
IS
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
2
2
14
3
31
4
53
8
1
0
1
2
30
1
47
4
3
1
7
0
5
0
29
4
Departures by Stage Distance (Statute Miles)
0
500
0
0
10
1
30
2
50
4
0
0
0
1
16
1
26
0
1
0
2
0
5
0
29
4
500
1000
0
0
2
1
1
2
3
4
0
0
1
1
11
0
17
2
2
1
3
0
1000
1500
1
1
0
0
0
0
2
0
2
2
1
0
1500
2500
0
0
2
1
1
0
1
0
2
0
1
0
2500
3500
0
0
3500
4500
1
1
4500
5500
Over
5500
*' Excludes General Aviation and Military Operations.
** Day: 7:00 AM - 10:00 PM
Night: 10:01 PM - 6:59 AM
C-5
-------
Table C-2b
Airport Activity Forecast
St. Louis - 1987
Aircraft
Type*
I
I
I
I
II Small
II Medium
II Medium
II Large
Range ^
Capability Model
Short-Medium
Medium
737
DC-9
Unspec .
! 727- 100
727-200
STOL Unspec.
Medium-Long -
707
DC-8
Unspec.
Short-Medium Unspec.
Medium,. '
Long S
Medium-Long \
DC- 10
L-1011
Unspec.
DC- 10
Unspec.
,.
747
Unspec.
***
Day
Night
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
Arrivals
. 3
1
107
17
20
2
64
2
35
3
50
0
50
0
12
0
35
34
Departures by Stage Distance (Statute Miles)
0
500
1
0
101
9
11
0
34
2
19
0
0
0
0
0
0
0
0
0
500
1000
2
1
6
8
7
1
24
0
13
2
0
0
0
0
0
0
0
0
1000
1500
1
1
4
0
2
1
0
0
0
0
0
0
17
17
1500
2500
1
0
2
0
1
0
50
0
50
0
12
0
0
0
2500
3500
3500
4500
0 i 18
0 17
1
4500
5500
Over
5500
* Excludes General Aviation and Military Operations.
** Models indicated os "Unspecified" may include current aircraft and/or new aircraft not yet in production.
*** Day: 7:00 AM - 10:00 PM
Night: 10:01 PM - 6:59 AM
C-6
-------
Table C-2c
Airport Activity Forecast
St. Louis-2000
Aircraft Type
I Unspecified
(737/DC-9
Type
with SAM)
I Unspecified
(727 Type
with
SAM)
I Unspecified
(707/DC-8
Type
with SAM)
II Small
II Medium
II Large
III Small
III Medium
III Large
IVSST
Day**
Night
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
Arrivals
17
4
14
0
29
5
52
8
13
2
118
19
136
21
28
4
None
Departures by Stage Distance (Statute Miles)
0
500
10
2
7
0
23
3
-28-
1
2
0
88
12
20
2
0
0
500
1000
7
2
4
0
6
2
- 19
3
4
0
30
7
22
2
0
0
1000
1500
3
0
2
3
1
0
40
8
8
2
1500
2500
i
3
1
3
1
33
5
12
2
2500
3500
3
1
21
3500
4500
4500
5500
4 !
8 I
Over
5500
0 ; ;
Excludes General Aviation and Military Operations.
*Day: 7:00 AM - 10:00 PM.
Night: 10:01 PM -6:59 AM.
C-7
-------
Table C-3a
Airport Activity
Dulles- 1972
Aircraft-
Type *
720B
707-320B/C
707-120B
DC-9-15
DC-8-55
DC-9-32
DC- 10- 10
VC-10
707-120/-320
727-200
727-100
737-100/-200
747-100
Turboprop
(STOL)
Arrivals
Day/Night **
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
1
0
6
1
13
2
11
0
8
2
3
0
2
0
1
0
2
0
2
2
17
2
3
0
4
0
2
0
Departures by Stage Distance (Statute Miles)
0
500
0
0
3
0
7
0
6
0
3
2
1
0
0
0
0
0
1
0
0
2
6
1
3
0
0
0
2
0
500
1000
0
0
0
0
0
0
5
0
1
0
2
0
0
0
0
0
1
0
1
0
2
0
1
0
1000
1500
0
0
0
0
3
0
1
0
0
0
0
0
1
0
9
1
0
0
1500
2500
1
0
2
1
3
2
3
0
2
0
0
0
2
0
2500
3500
0
0
0
0
0 .
0
3500
4500
1
0
1
0
1
0
4500
5500
.'
Over
5500
* Excludes General Aviation and Military Operations.
** Day: 7:00 AM - 10:00 PM
Night: 10:01 PM - 6:59 AM
C-8
-------
Table C-3b
Airport Activity Forecast
Dulles-1987
Aircraft
Type*
I
I
I
I
II Small
II Medium
II Medium
II Large
Rcncs tir
Capability Model
Short-Medium <
Medium
737
DC-9
Unspec.
[727-100
727-200
STOL Unspec.
Medium-Long <
707
DC- 8
Unspec.
Short-Medium Unspec.
Medium <
Long <
Medium-Long <
fDC-10
L-1011
Unspec.
fDC-10
Unspec.
i
747
Unspec.
* **
Day
Night
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
Arrivals
4
0
23
0
23
3
13
13
17
0
11
3
4
0
11
1
10
0
8
0
10
0
12
0
36
0
Departures by Stage Distance (Statute Miles)
0
500
4
0
8
0
8
2
0
13
8
0
4
3
0
0
7
1
0
0
0
0
0
0
0
0
0
0
500
1000
15
0
3
0
7
0
9
0
1
0
0
0
1
0
0
0
0
0
0
0
0
0
9
0
1000
1500
12
1
6
0
2
0
0
0
3
0
0
0
0
0
0
0
0
0
0
0
1500
2500
4
0
0
0
10
0
8
0
10
0
12
0
18
0
2500
3500
0
0
0
0
3500
4500
4
0
9
0
4500
5500
Over
5500
* Excludes General Aviation and Military Operations.
** Models indicated as "Unspecified" may include current aircraft and/or new aircraft not yet in production.
*** Day: 7:00 AM - 10:00 PM
Night: 10:01 PM - 6:59 AM
C-9
-------
Table C-3c
Airport Activity Forecast
Dulles-2000
Aircraft Type*
I Unspecified
(737/DC-9
Type
with SAM)
I Unspecified
(727 Type
with
SAM)
.1 Unspecified
(707/DC-8
Type
with SAM)
II Small
II Medium
II Large
III Small
III Medium
III Large
IVSST
n **
Day
Night
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
D
N
Arrivals
2
0
3
0
22
0
19
2
32
4
41
5
64
8
53
5
60
7
10
0
Departures by Stage Distance (Statute Miles)
0 500
500 1000
2
0
3
0
8 14
0 . 0
16 3
2 0
11 3
0 0
0 5
0 1
41 6
3 2
6 : 15
o ; i
0 ! 16
0 1 2
i
0 1 0
o i o
1000 i 1500
1500 |2500
i
. j
j
i
i
i
j
i
6 12
1 3
15 I 7
1 i 2
17 j
3 i
19 ! 4
2 | 0
0 | 28
0 | 2
0 1 0
0 1 0
2500
3500
14
1
9
2 |
3500
4500
-
4500
5500
0 16 ;
0 3 :
064
0 010
Over
5500
Excludes General Aviation and Military Operations,
k*Day: 7:00 AM - 10:OOPM.
Night: 10:01 PM - 6:59 AM.
C-10
-------
APPENDIX D
DERIVATION OF CLIMB GRADIENT FOR
ENGINE OUT CONDITION
W
Center of Gravity
Assume a simple linear first approximation model of flight performance for an aircraft.
Define the following parameters:
V = Velocity
T = Thrust
D = Drag
W = Weight
0 = Climb Angle
Then, summing forces through the center of gravity
and
T - D - Wsin 8 = -T- , along the thrust axis
L - Wcos 8 = 0, normal to the thrust axis
D-l
-------
For unaccelerated climb -r- = 0 , so that these two
at
equations combine to give: sin 9 = TTT , or, for small climb angles,
sin 6 =* tan 0= y = climb gradient
= 1. 2.
y w "w
W= L cos 8 ^ L for small 0
_ T D
y~W~L
D
7 W L
where
N = number of engines and f = net thrust/engine.
For one engine out, the climb gradient y' is
-VN" A P D
y ~vw/ Vrr
Solving for the net thrust per engine,
_ w /D .
Substituting this back in the equation for y gives:
N \ / 1 \ D
which is the approximate climb angle for an engine thrust setting, for all
(N) engines, equal to that necessary to maintain a climb angle y1 with
(N - 1 ) engines or one engine out. For this simple model, the lift to drag
ratio (L/D) is assumed constant in all cases.
D-2
-------
EPA 550/9-75-024
t. Government Atcettion No.
'.. recipient'* Catalog No,
4. Titla end Subtitle
i.
l Dale
National Measure of Aircraft Noise Impact
Through the Year 2000
April 1975
6. Performing OiQortlxation CcJa
7. Aulhor(i)
Carroll Barrel, Larry Goefby, and
Louis Sutherland
8. Performing Crganiiotlon Report No.
WC R 74-13
9. Performing Orgonito'ion N
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