5. Noise Assessment
This chapter describes the change in noise levels through the introduction of Super Hornet at RAAF Base
Amberley. This involves the review of the existing noise environment around the Base and a quantitative
description of the likely noise impacts. It identifies noise sensitive land uses and the potential impact on those
uses, as well as considers the need for mitigation measures, costs and offsets.
The following information is provided:
1)
Background to aircraft noise;
2)
Explanation of noise and how it is measured;
3)
The existing noise environment around the Base;
4)
Description and comparison of Super Hornet and F-111 aircraft noise in regard to flight path and altitude,
maximum sound levels, number of flights and time period of noise (noise impacts need to be considered
in regard to all of these factors);
5)
Assessment of potential effects of noise;
6)
Mitigation and monitoring measures;
7)
Implications for future land use development around the Base; and
8)
Summary of the noise assessment.
5.1. Background
RAAF Base Amberley has been operating as a military airfield since the 1940’s. Its prime purpose is the
conduct of military aircraft operations to support the defence of Australia which is an essential responsibility of
the Australian Government. People in the surrounding community have experienced and will continue to
experience aircraft noise as a result of aircraft operations.
Where operational requirements allow, Defence modifies its aircraft operations to limit noise impacts on the
community. Chapter 2 describes how Super Hornet flying operations have been designed to achieve
operational goals while reducing potential noise impacts. This chapter provides a description of the potential
change in noise environment.
5.2. Explanation of Noise
In order to understand the impact of aircraft noise on people, it is important to understand what sound is and
how it is described.
People’s ears respond to sound pressure. Because the loudest sounds (highest sound pressures) that we
can comfortably detect are a trillion times higher than those that can be barely detected (lowest sound
pressures), a linear scale to represent the intensity would be very unwieldy. As a result, a logarithmic unit
106
known as the decibel (dB) is used to represent the level of a sound. A sound level of 0 dB is approximately the
threshold of human hearing. On the other hand, sound levels as high as 130 -140 dB can be felt as pain.
Appendix I.1 provides more information regarding sound and its characterisation.
A chart showing the typical decibel level for common sounds is shown on Figure 5-1.
Noise is defined as “unwanted sound”, with the sound being greater than background sound levels and
therefore being noticeable. Busy suburbs can have instantaneous sound levels of up to 60 to 70 dB(A) and as
high as 80 to 90 dB(A) near major roads when noise sources such as cars and trucks pass by or when lawn
mowers are used. Quiet rural localities generally have ambient levels around 30 to 40 dB(A) while suburban
areas might have ambient levels around 35 – 50 dB(A) (US Department of the Navy, 2003).
When a sound changes in level, the minimum decibel increase or decrease required before we can recognise
a change varies. Table 5-1 shows the necessary change in decibel level for a change in perception of that
sound to be noticed. For example, if the decibel level increases by 10 dB, then subjectively the perception
would be that the loudness of the sound had doubled. At low frequencies, the decibel change required for a
given change in perception is reduced.
„
Table 5-1 Perception of Increases in Decibel Level
Perception
Decibel
Imperceptible Change
1dB
Barely Perceptible Change
3dB
Clearly Noticeable Change
5dB
About Twice as Loud
10dB
About Four Times as Loud
20dB
Noise levels, including aircraft noise, are commonly measured in dB(A). The ‘A’ refers to a weighting that
represents the response of the human ear to sound.
107
108
Source: Main Roads, 2008
„
Figure 5-1 Common Sounds at their Decibel Level
5.2.1.
Maximum Sound Level - L(A)max
In Australia, a commonly used measure of aircraft noise is L(A)max. L(A)max is the highest instantaneous
sound pressure level measured during a single aircraft flight. This metric provides some indication of
interference with speech, listening to the television, sleeping or other common activities.
An L(A)max outdoors of around 70 dB(A) or below is unlikely to interfere with verbal communication indoors
even with an open window. Aircraft noise up to this level is likely only to be momentarily intrusive, if at all.
Inside a building, an aircraft noise event is unlikely to interfere with conversation or listening to the radio or
television if it has an L(A)max of less than 60 dB(A) (DOTRS, 2000; Southgate, 2000; Connor 2007). The
fabric of a building reduces noise from outside to inside by around 10 dB(A) with an open window and by 23 –
28 dB(A) with windows closed (up to 35 dB(A) for a very well insulated building) (Morrow et al, 2003). This
means that an L(A)max from an aircraft flight needs to exceed 70 to 80 dB(A) outdoors before indoor activities
such as conversation or listening to a television in a building with an open window is likely to be interrupted.
As bedrooms are typically quieter environments, an L(A)max of as low as 45 to 50 dB(A) indoors may
interfere with sleep (enHealth, 2004; AS2021-2000). Sleep inside a house may therefore be interfered with by
external noise with a sound level as low as L(A)max 50 to 60 dB(A), depending on whether windows are
closed or open.
L(A)max is just one way of describing noise. It indicates the maximum sound level which may be experienced,
but it does not give any information about how long this level will last or how frequently it will occur. NX
contours provide information about the frequency of noise events.
5.2.2.
NX Contours
The number of actual movements past a particular location is an important parameter in determining whether
noise annoyance may be experienced. For example, a small number of very short passing flights may not be
as annoying as a very large number of passing flights of lesser sound level. People living near to major
airports such as Brisbane can experience 100 – 200 flights on a daily basis.
NX contours represent the number of movements per day that would result in a nominated L(A)max noise
level at the given location. So the N70 represents the number of movements at a given location that result in
an aircraft noise level over L(A)max 70 dB(A), for an average flying day.
5.2.3.
Time Dimension of Sound
It is also useful to describe noise in terms of how long the sound may be expected to be experienced. During
an aircraft over flight, the sound begins at the ambient level, gradually rises to a peak of the L(A)max and then
decreases as the aircraft flies away.
109
5.2.4.
Transparent Noise Information Package
The Federal Government Department of Transport and Regional Services (DOTARS) developed a computer
program that can be used to better inform the community concerning issues surrounding aircraft noise. The
program, the Transparent Noise Information Package (TNIP), can calculate and display detailed information
on the aircraft modelled including flight track information.
TNIP is able to display noise contours such as NX and L(A)max, together with comparisons of different noise
metrics discussed in the draft PER.
A TNIP has been prepared for Super Hornet flying operations and is available on CD. A copy of the TNIP may
be requested through post, email and fax contacts at 1.4.1 or by calling 1 800 451 766.
5.3. Integrated Noise Model
Noise contours are developed by noise modelling. In Australia, the model used is the INM which was
developed by the Federal Aviation Authority of the USA. Detailed information on the INM is provided in
Appendix I.2.
Defence has used the INM to model the noise levels around RAAF Base Amberley from all aircraft planned to
operate there including the Super Hornet. Defence uses a standard 10-year horizon for noise forecasts.
Noise models for Amberley were prepared beginning in 2008; hence 2018 has been used as an appropriate
forecast date. INM has produced a range of noise contours including L(A)max for Super Hornet and other
aircraft.
5.4. Current Noise Environment around RAAF Base Amberley
5.4.1.
Ambient Noise Levels
In order to determine the likely noise impact due to aircraft noise, it is necessary to consider the existing
ambient noise level conditions. An aircraft flying over or near a quiet rural type area will cause a different
impact than one flying over or near a more noisy suburban, commercial or industrial area. Expectations of
residents are related to their surrounding environment. It has been found that annoyance response to aircraft
noise is dependent on the background noise level (Ohrstrom et al 2007, Lim et al 2008).
RAAF Base Amberley is located on the western side of Ipswich City, surrounded by a mixture of industrial,
agricultural and residential land uses. Various areas around Amberley are already impacted by sources of
noise other than aircraft, such as road and rail traffic, the Willowbank Raceway and mining activities.
Short term attended noise measurements were conducted in April 2009 at nine locations. For this purpose,
four 15-minute measurements were conducted at each of the locations over a 24 hour period. Figure 5-2
shows the locations relative to the Base.
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Ironbark
A description of the noise environment in the suburbs where the noise measurements were taken is provided:
„
„
„
„
„
„
Location 1 (Ironbark) - Ironbark is located north of the Base in a quiet, mainly agricultural area
surrounded by open fields and well dispersed residential dwellings near to the Brisbane Valley Highway.
Local ambient noise throughout the 24 hour period included traffic along Ironbark Road (trucks, cars),
local farm animals, distant traffic and bird song;
Locations 2 and 3 (Walloon 1 and Walloon 2) - Walloon is a residential area north-west of the Base,
surrounded by open fields. Common background noise ranged from bird song, distant traffic, jets
overhead and rail noise;
Location 4 (Karrabin) - Karrabin is a quiet rural residential area surrounded by open fields and well
dispersed residential dwellings. Typical noise around the area included bird song, distant traffic,
occasional light aircraft, jets passing overhead and train noise;
Location 5 (Blacksoil) - Blacksoil is a quiet rural residential area surrounded by open fields, residential
dwellings and near to West Moreton Anglican College. Typical noise around the area included bird song,
distant traffic and occasional light aircraft;
Locations 6 and 7 (Leichhardt 1 and Leichhardt 2) - Leichhardt is a built up residential area with some
agricultural pockets of land surrounding the area close to the Base and west of Ipswich. There is also a
sizable golf course within Leichhardt. Common background noise included bird song, local farm animals,
distant traffic and trains passing along the nearby train line; and
Locations 8 and 9 (Yamanto 1 and Yamanto 2) -Yamanto is located south-east of the Base and is
mainly a residential area, surrounded by open fields and close to the Cunningham Highway. Common
background noise included bird song and distant traffic.
Appendix I.3 provides the data collected from the noise monitoring.
The monitoring results identify that L(A)max values are currently at or above 70 dB(A) for most locations
visited, both day and night. These levels could possibly interfere with communication. The majority of
locations have an L(A)max in the range 70 – 80 dB(A). Some areas have noise levels exceeding L(A)max
70 dB(A) due to noise sources other than aircraft and these noise levels are not necessarily considered to be
a source of annoyance or disturbance.
Three of the nine monitoring locations exhibited noise levels above L(A)max 70 dB(A) (where noise may be
noticeable indoors when there are open windows) during all of the times when measurements were made
(Walloon 1, Karrabin and Yamanto 2). Ironbark and Leichhardt 2 also exhibited noise levels above L(A)max
70 db(A) for the majority of the day measurements. Noise monitoring identified that the quietest period of the
day was between the hours of midnight and 5 am.
112
Whilst monitoring locations recorded noise levels above L(A)max 70 dB(A), noise levels at monitoring
locations do not exceed L(A)max of 90 dB(A). Additionally, noise monitoring levels above 60 dB(A) are
generally not experienced for longer periods than 10% of the 15 minute sample time.
5.4.2.
Existing Meteorological Conditions
The actual received noise level on the ground will be affected by the meteorological conditions at the time.
Wind blowing to a receiver from a noise source (the receiver therefore being downwind of the noise source)
will result in increased noise levels while reduced noise levels would be experienced in the opposite (upwind)
direction.
Year round the prevailing wind is generally from the south and east. Therefore areas to the north would
experience elevated noise levels for most of the year. In spring, summer and autumn, easterly winds would
lead to elevated noise levels areas to the west of the Base, particularly Jeebropilly, Walloon and Thagoona.
In winter, Yamanto and Churchill could experience increased noise levels due to north-westerly winds (refer to
Appendix I.4 for wind rose information).
In addition, there can be increased noise levels around dusk or dawn or during the evening time if a
temperature inversion occurs.
A temperature inversion is when the air temperature is coolest right next to the ground and gets warmer as
height increases above the ground. When this happens, sound waves are bent back towards the ground and
sound can then be heard at larger distances from the noise sources. Temperature inversions are very
common in some areas and occur on almost all calm clear nights and less frequently, under certain daytime
conditions. In the context of perception of aircraft noise operating at RAAF Base Amberley, this means that
aircraft noise may be audible over larger distances from the Base during inversion conditions.
To obtain an indication of the number of occasions when temperature inversions occur around RAAF Base
Amberley , the meteorological data recorded by the Bureau of Meteorology (BoM) at Amberley was reviewed,
and the CSIRO meteorological model ‘TAPM’ was applied to obtain the Pasquill Atmospheric Stability Class
data. This data indicates that for many nights during the year, particularly between 8 pm and midnight,
inversion conditions occur. The frequency of occurrence of temperature inversions was determined through
analysis of one year of meteorological data generated by TAPM. Throughout the year temperature inversions
are estimated to occur 44% of days between 8 pm and midnight.
These effects of weather particularly apply to noise generated at or close to ground level, such as aircraft
taxiing or increasing power prior to take-off. Wind and temperature inversions have a lesser effect on the
noise experienced from airborne aircraft.
The INM does not allow for the effect of meteorological conditions, such as wind and temperature inversions,
on noise propagation. Any forecast effects must therefore be generalised.
113
5.4.3.
Existing Aircraft Operations
A range of aircraft currently operate from RAAF Base Amberley. The F-111 flies the greatest number of
movements from the Base, followed by the C-17.
Table 5-2 shows the estimated historical number of F-111 movements at RAAF Base Amberley between
1998 and 2003 (1999 was not available).
„
Table 5-2 Estimated F-111 Movements at RAAF Base Amberley
Year
1998
2000
2001
2002
2003
F-111 movements
6,566
5,520
5,525
5,905
5,643
Source: GHD 2005
The RAAF has planned for 4,648 Super Hornet movements per year at RAAF Base Amberley. F-111s have
historically flown more movements than this, with over 6,500 movements at the aircraft’s operational peak.
The number of F-111 movements per year has been gradually declining over recent years, as the aircraft
ages and approaches its retirement.
In 2008, the F-111 fleet flew approximately 2,000 movements at RAAF Base Amberley, equating to the
average 8-10 movements per day discussed in Section 2.4.4.1. Data since then indicates the number of
movements is further reducing.
Defence has recently installed a Noise and Flight Path Monitoring System (NFPMS) at RAAF Base Amberley
(refer to Section 5.7.4.). In the future, this system will help Defence monitor the noise created by aircraft
operating from the Base.
Preliminary movement data from the NFPMS indicates that in the three months from February to April 2009,
214 F-111 movements were flown. This equates to just under 1,000 movements per year, roughly a quarter
of the rate expected from the Super Hornet. The low number of F-111 movements is due to a general decline
in the availability of the aircraft, as a result of increasing maintenance requirements, and the ending of F-111
pilot training in 2008.
There were 146 C-17 movements in the same three months, which equals just under 600 movements a year.
This indicates that the C-17 fleet at Amberley is currently flying close to its expected annual rate of
movements of 696.
Although C-17 operations are close to full rate, the significant decline in F-111 movements indicates a
generally low level of current aircraft noise around RAAF Base Amberley. This increases the likelihood of the
introduction of the Super Hornet being noticeable to the community.
114
The noise complaints within 37 km of RAAF Base Amberley for the period February 2007 until June 2009 are
shown in Appendix I.5. Out of the 41 complaints in total, ten relate to F-111 Airshow Display Practice on
three days. Otherwise, the majority are due to circuits and are widely distributed.
Overall, given the number of aircraft movements from RAAF Base Amberley, the number of recorded
complaints is small.
5.5. Description of Super Hornet Aircraft Noise
This section describes the noise changes that are predicted to occur as a result of the introduction of the
Super Hornet. At maximum power (in full afterburner), the Super Hornet produces more noise than the F-111.
This is due to a number of reasons, most notably the greater thrust the Super Hornet engines produce. The
absolute noise level at maximum power does not, however, adequately describe the potential impact of Super
Hornet. This depends on numerous factors, such as flight paths, number of movements, flying times and
planned respite periods. These factors are described as follows.
5.5.1.
Flying Operations
It is likely that the most noticeable change as a result of the introduction of the Super Hornet is a greater
number of daily aircraft movements than the F-111. As described in Chapter 2, planned Super Hornet
movements on an average day are approximately twice the 2008 movements of the F-111.
A typical flying day for the Super Hornet will have around 10 total flights which equates to 20 movements
(arrivals and departures). The maximum flying day will have around 24 flights or upwards of 48 movements.
A given location will not necessarily experience noise from every one of the planned movements, as they will
be distributed around the Base according to various flight paths. Additionally, Super Hornet movements will
tend to be gathered in formations of two to four aircraft, reducing the number of noise events experienced per
day.
The Super Hornet is operationally a very different aircraft to the F-111 aircraft and therefore flies a different
profile, including flying different flight paths.
115
5.5.1.1.
Profiles
A typical Super Hornet arrival height profile shows the aircraft height versus distance from the touchdown
point on the runway, and is shown in Figure 5-3. For comparison purposes, the F-111 arrival profile is also
shown. The Super Hornet maintains altitude longer than the F-111 before descending to 1,500 ft (450 m) to
complete an Initial and Pitch arrival. The F-111 also conducts an Initial and Pitch arrival but starts from a lower
altitude.
12000
Altitude (Feet)
10000
8000
6000
F-111
ASH
4000
2000
116
0
-50 -47 -44 -41 -38 -35 -32 -29 -26 -23 -20 -17 -14 -11 -8 -5 -2
Distance (km)
„
Figure 5-3 Typical Super Hornet and F-111 Arrivals
Typical Super Hornet and F-111 departure profiles are shown in Figure 5-4. After leaving the runway, the
Super Hornet climbs rapidly, passing through 1,500 ft (450 m) at about 3 km from start of roll, passing through
5,000 ft (1,520 m) at about 6 km and achieving 17,000 ft (5,150 m) at approximately 19 km distance. The
F-111 departure profile shows the F-111 at 1,500 ft (450 m), about 5 km from start of roll and passing through
5,000 ft (1,520 m) at about 11 km. The F-111 climb, on departure, is not as steep as that for the Super Hornet
and therefore is closer to the ground for a longer distance.
When departing from and arriving at the Base, the F-111 flies much closer to the ground for a much longer
time and distance compared to the Super Hornet.
18000
16000
Altitude (Feet)
14000
12000
10000
8000
F-111
6000
ASH
4000
2000
0
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17
Distance (km)
„
Figure 5-4 Typical Super Hornet and F-111 Departure Profile
5.5.1.2.
Flight Paths
The Super Hornet arrival, departure and circuit flight paths are shown on Figure 2-7, Figure 2-8 and Figure
2-11. F-111 arrival, departure and circuit flight paths are shown on Figure 2-12, Figure 2-13 and Figure
2-14. These show aircraft height at any given distance from either touchdown or start of take-off roll. The
height scale is colour coded and ranges from 0 (ground level) to greater than 15,000 ft (4,550 m). The height
of a given aircraft at any location within about 28 km of the Base can be seen.
The flight path figures further illustrate that the Super Hornet flies higher on arrivals and departures than the
F-111. They also show the planned Super Hornet flight paths are concentrated to the north, west and south of
the Base, to limit the noise impact on suburbs of Ipswich, located to the east.
The RAAF has designed Super Hornet flight paths to concentrate potential noise effects in limited, less
populated areas. This decision was taken to limit the number of people potentially affected by noise and
protect areas of future development. While a small number of areas will be more exposed to aircraft over-flight
compared to F-111 operations, the total number of aircraft movements is still small.
117
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AUSTRALIAN
SUPER HORNET
PER
FIGURE 5-6
μ
Projection: WGS 84 - Zone 56
0
85
Super Hornet L(A)max Contours
2
4
6
8
Kilometres
Scale 1:250,000 on A3
10
I:\QENV\Projects\QE09512\Spatial\ArcGIS\Arc_MXD\Report_Figures\Figure_5-6_ASH_Lamax_70-110_Contours_v4.mxd Produced: 29/7/2009.
47 78
111 99
93 11
96
5.5.1.3.
L(A)max
The potential noise impacts of the Super Hornet can be illustrated through comparison of the L(A)max for the
F-111 aircraft with the L(A)max for the Super Hornet. Figure 5-5 and Figure 5-6 show the forecast Super
Hornet and the current F-111 L(A)max contours for 70 dB(A) to 100 dB(A). These contours show the highest
instantaneous noise level that is expected to be experienced at locations around the airfield during all
operations of the respective aircraft type. The noise level shown is not heard at all locations simultaneously
but can reach that value at that location at a point of time due to an operation of that aircraft.
Table 5-3 identifies the number of dwellings and indicative population located within each of the L(A)max
noise contours for both the Super Hornet and F-111 (orange – higher comparative number, green – lower
comparative number). The relevant population was calculated by multiplying the average persons per
household by the number of residential property lots within each contour. The average persons per
household were determined for the Brisbane Statistical District area (2.6 persons per household) as of the
2006 Census.
While the population around RAAF Base Amberley is expected to grow, it is not possible to accurately
estimate the distribution of this growth. Regardless, the analysis in Table 5-3 gives a comparison of the effect
of the replacement of the F-111 with the Super Hornet.
„
Table 5-3 Estimated Population within the Super Hornet and F-111 L(A)max Contours
L(A)max
Contour
Super Hornet Dwellings
Super Hornet Population
F-111 Dwellings
F-111 Population
70 dB(A)
255,183
663,475
202,492
526,479
75 dB(A)
206,104
535,870
133,278
346,523
80 dB(A)
132,217
343,764
77,688
201,989
85 dB(A)
50,211
130,548
39,217
101,964
Population
and Dwelling
Percentage
Change F-111
to Super
Hornet
26% increase
55% increase
70% increase
28% increase
11% decrease
90 dB(A)
11,319
29,429
12,769
33,119
95 dB(A)
4,475
11,635
6,752
17,555
100 dB(A)
1,206
3,135
2,294
5,964
34% decrease
47% decrease
120
For each contour level category at 85 dB(A) and below, more people are included in the Super Hornet
contours than in the F-111 contours. As illustrated in Figure 5-1, 85 dB(A) is equivalent to the sound of a
large truck driving down the road outside a house or office. From 90 dB(A) to 100 dB(A), where greater
disturbance is possible, the number of dwellings and population is significantly less for Super Hornet
compared to the F-111.
The F-111 operations spread higher L(A)max noise levels around the Base, primarily due to the influence of
the training circuits. For example, the F-111 L(A)max 90 dB(A) contour extends to East Ipswich, Tivoli and
Newtown in the east while to the west, it reaches Walloon and Mount Marrow and to the west of Jeebropilly.
Also, due to the F-111 having multiple departure flight paths in a range of directions from the Base, many
areas surrounding the Base, particularly to the north and south, have L(A)max noise levels of 70 to 80 dB(A).
Due to the use of Runway 15/33 by the Super Hornet and in particular the arrival flight paths, those areas
mentioned in regard to F-111 will have a reduction of 5 to 10 dB(A) L(A)max. Areas such as Banks Creek,
Mount Nebo and England Creek could have a reduction from L(A)max 75 to less than L(A)max 65 dB(A).
However, other areas previously exposed to L(A)max of 70 to 80 dB(A) due to F-111 flights may now have
levels up to 95 dB(A) e.g. some sections of Mount Forbes could experience an increase from L(A)max 75 to
L(A)max 95 dB(A) while some areas in Peak Crossing would increase from L(A)max 80 to L(A)max 95 dB(A).
To the north, some areas in Wivenhoe Pocket could have an increase from L(A)max 80 to L(A)max 95 dB(A).
Other areas experiencing increases would be to the north and east under the Super Hornet arrival and
departure flight paths e.g. areas previously unexposed such as Pullenvale, Brookfield, Mount Coot-tha, The
Gap, Ashgrove would have L(A)max levels up to 85 dB(A).
Super Hornet noise in these areas would be experienced from over-flights at higher altitudes and would be
noticeable, particularly outside, depending on the levels of other noise such as urban traffic.
The relative number of sensitive public receivers located within the Super Hornet and F-111 L(A)max contours
are shown in Table 5-4 and Table 5-5 (orange – higher comparative value, green – lower comparative value).
These have been calculated based on a commercial dataset provided by MapInfo (StreetPro).
These tables provide a current snapshot in time but are valid for current comparison of the two aircraft types.
121
„
Table 5-4 Sensitive Receivers within the Super Hornet L(A)max Contours
Super Hornet L(A)max Contours
Cultural Feature
70
dB(A)
75
dB(A)
80
dB(A)
85
dB(A)
90
dB(A)
95
dB(A)
100
dB(A)
Health, Police and Emergency
Services
61
42
26
1
1
0
0
Education
151
121
71
24
5
3
1
Aged Care
29
23
15
9
1
0
0
Places of Worship
142
106
60
18
2
0
0
Accommodation
5
2
2
2
2
0
0
Sport, Recreation, Leisure and
Cultural Facilities
67
52
31
10
7
3
2
Cemetery
17
14
11
6
2
1
0
TOTAL
472
360
216
70
20
7
3
„
Table 5-5 Sensitive Receivers within the F-111 L(A)max Contours
100dB(A)
95dB(A)
90dB(A)
85dB(A)
80dB(A)
75dB(A)
Cultural Feature
70dB(A)
F- 111 L(A)max Contours
Health, Police and Emergency
Services
21
15
10
10
3
2
1
Education
58
48
35
29
13
9
7
Aged Care
8
8
7
5
1
0
0
Places of Worship
38
27
18
15
6
3
3
Accommodation
5
5
5
5
1
1
0
Sport, Recreation, Leisure and
Cultural Facilities
32
29
22
19
12
9
5
Cemetery
11
10
5
3
0
0
0
TOTAL
173
142
102
86
36
24
16
For the lower L(A)max levels between 70 – 80 dB(A), the number of sensitive receivers, apart from
‘accommodation’, is significantly higher for the Super Hornet than for the F-111. However, above 80 dB(A),
where disturbances are more likely, the current F-111 operations affect a larger number of sensitive receivers
compared to the planned Super Hornet operations.
The L(A)max figures indicate the maximum noise level which may be experienced at a location as a result of
all flight paths planned in the noise forecast models. The maximum noise level may be experienced only once
a year, depending on the exact location under consideration. The number of times per day noise may be
experienced should also be taken into account in considering noise impacts. NX contours provide this
information.
122
5.5.1.4.
NX Contours
Figure 5-7, Figure 5-8 and Figure 5-9 show the Super Hornet N70, N85 and N100 curves respectively.
These curves represent the number of movements at a given location that result in an aircraft noise level over
L(A)max 70 dB(A), 85 dB(A) and 100 dB(A) respectively for an average flying day. NX contours do not take
into account planned periods of respite from Super Hornet noise such as weekends or over Christmas. The
equivalent information for the F-111 is provided in Figure 5-10, Figure 5-11 and Figure 5-12.
N70 Contours
The N70 contours show that, on average, 1 to 5 Super Hornet movements would be likely to be at least
perceptible over a large area each day. At that level, the aircraft noise would not necessarily be particularly
noticeable relative to other noise sources in the area and would be unlikely to interfere with communication
indoors (refer to Section 5.2.1). Closer to the Base, the number of movements resulting in L(A)max over
70 dB(A) increases to 15 – 20 on average on a daily basis.
N85 Contours
Table 5-6 provides an outline of the range of N85 flights (equivalent to the sound of a large truck driving
outside a house) for suburbs surrounding the Base relating to the F-111 and Super Hornet. The N85 contours
show the area where maximum noise levels could be expected to start interfering with communication indoors
(even if windows are closed).
123
Sensitive Receiver
Accomodation
(
!
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Retirement Facility
(
!
Boarding Kennel
(
!
Cemetery
(
!
Childcare
(
!
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(
!
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(
!
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(
!
(
!
37
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(
!
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3
30 32
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(
!
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(
!
13
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LEGEND
RAAF Base Amberley
Number of Movements > 70dB(A)
per Average Flying Day
5
(
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μ
Projection: WGS 84 - Zone 56
0
Super Hornet N70 Contours
1
2
3
Kilometres
Scale 1:100,000 on A3
4
I:\QENV\Projects\QE09512\Spatial\ArcGIS\Arc_MXD\Report_Figures\Figure_5-7_N70_Contours_v2.mxd Produced: 8/7/2009.
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RAAF Base Amberley
Number of Movements> 85dB(A)
per Average Flying Day
50
11 47
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AUSTRALIAN
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μ
Projection: WGS 84 - Zone 56
0
Super Hornet N85 Contours
1
2
3
Kilometres
Scale 1:100,000 on A3
4
I:\QENV\Projects\QE09512\Spatial\ArcGIS\Arc_MXD\Report_Figures\Figure_5-10_ASH_N85_Contours_v4.mxd Produced: 29/7/2009.
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50
LEGEND
RAAF Base Amberley
Number of Movements > 100dB(A)
per Average Flying Day
5
11 47
!78
((
!
(
!
AUSTRALIAN
SUPER HORNET
PER
FIGURE 5-9
10
15
(
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39
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(
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Projection: WGS 84 - Zone 56
0
Super Hornet N100 Contours
1
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3
Kilometres
Scale 1:100,000 on A3
4
I:\QENV\Projects\QE09512\Spatial\ArcGIS\Arc_MXD\Report_Figures\Figure_5-11_ASH_N100_Contours_v4.mxd Produced: 29/7/2009.
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LEGEND
RAAF Base Amberley Number of Movements > 70dB(A)
per Average Flying Day
5
10
AUSTRALIAN
SUPER HORNET
PER
FIGURE 5-10
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Projection: WGS 84 - Zone 56
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F111 N70 Contours
1
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Scale 1:100,000 on A3
4
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LEGEND
RAAF Base Amberley Number of Movements> 85dB(A)
per Average Flying Day
5
10
AUSTRALIAN
SUPER HORNET
PER
FIGURE 5-11
15
20
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Projection: WGS 84 - Zone 56
0
F111 N85 Contours
1
2
3
Kilometres
Scale 1:100,000 on A3
4
I:\QENV\Projects\QE09512\Spatial\ArcGIS\Arc_MXD\Report_Figures\Figure_5-11_F111_N85_Contours_v5.mxd Produced: 3/8/2009
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LEGEND
RAAF Base Amberley Number of Movements> 100dB(A)
per Average Flying Day
AUSTRALIAN
SUPER HORNET
PER
5
10
FIGURE 5-12
15
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1
2
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Scale 1:100,000 on A3
4
I:\QENV\Projects\QE09512\Spatial\ArcGIS\Arc_MXD\Report_Figures\Figure_5-14_F111_N100_Contours_v3.mxd Produced: 29/7/2009.
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„
Table 5-6 F-111 and Super Hornet N85 Overflights for Suburbs Surrounding RAAF Base,
Amberley
Suburb
Range of N85 Flights within Suburb
F-111
Super Hornet
Amberley
0-15
15
Blacksoil
0
5
Brassall
0
0
Churchill
0
0-5
Coalfalls
0
0
Deebing Heights
0
0-5
Ebenezer
0
0
Flinders View
0
0
Glamorgan Vale
0
0-5
Haigslea
0
0
Ipswich
0
0
Ironbark
0
5
Jeebropilly
0
0
0-10
5-10
Leichhardt
0
5-15
Muirlea
0
0
Mutdapilly
0
0
Karrabin
Newtown
0
0
North Ipswich
0
0
One Mile
0
10-15
Pine Mountain
0
0-5
0-10
5-15
Raceview
0
0
Ripley
0
0
Sadlier Crossing
0
0
Silkstone
0
0
Thagoona
0
0
Walloon
0
0-5
Wanora
0
0-5
West Ipswich
0
0
Willowbank
0
0-10
Woodend
0
0
Wulkuraka
0
0-15
Purga
130
On an average flying day, 5 – 10 of movements that result in a L(A)max of 85 dB(A) could be expected in
areas to the north and south of the Base, the western edge of Ipswich, Willowbank, eastern parts of Walloon
and Karrabin. In general, these areas will all experience an increase in movements above 85 dB(A) due to
the introduction of the Super Hornet.
N100 Contours
The N100 contours show the average number of movements outside the Base that result in a L(A)max of
100 dB(A) is in the range of 5 – 10, predominantly in areas to the north of Runway 15/33 including Ironbark
and to a much smaller extent to the south. This is primarily due to the significant arrival activity on Runway 15
and, to the south, due to the significant departure activity on Runway 15. Outside these contours, movement
numbers are less than 5 on average reducing in audibility as distance increases from the Base. By
comparison, F-111 movements creating greater than 100 dB(A) are fewer than 5 per day on average in areas
outside of the Base.
Note that the NX contours depict expected noise levels on an average flying day. The number of movements
associated with maximum noise levels shown in these contours may vary from day to day. On some days,
particularly weekends, there is expected to be no Super Hornet flying. On other flying days, there may be up
to twice the average number of movements.
The increase in Super Hornet movements will result in an increase in noticeable noise events in suburbs
around the Base on flying days. Super Hornet movements will generally be grouped into formations of two to
four aircraft, which will reduce the total number of noise events experienced per day. Regardless, the increase
in numbers of noise events is likely to be noticeable.
5.5.1.5.
Time of Noise
Maximum noise levels described by L(A)max will only be experienced for short periods of time as aircraft fly
past. For Super Hornet flying operations, noise will generally be experienced over a period of 30 to 90
seconds. Over this time, the noise level will gradually increase to a peak equivalent to the L(A)max value and
then decline as the aircraft flies away from the receiver.
The noise impact associated with military aircraft is less for a given L(A)max due to the relatively small
"exposure time”, as compared to the “drone” of General Aviation aircraft which lasts a longer period of time.
This reflects the difference in speed between military and civilian aircraft.
5.5.1.6.
Impact of Noise on Activities on the Base
F-111s have operated from RAAF Base Amberley since 1973 and therefore Base personnel are familiar with
managing the impacts of aircraft noise. There are existing procedures on-Base to mitigate noise impacts,
including regular noise audits, mandatory areas for use of hearing protection devices and management
controls to limit noise exposure over time.
131
Figure 5-5 shows the current F-111 L(A)max contours over the Base. Buildings on-Base are located to the
western side of the runways. The buildings closest to the runways currently experience L(A)max in the range
85 dB(A) – 102 dB(A). The group of buildings further west, which includes the Amberley Childcare Centre, is
exposed to L(A)max in the range 82 dB(A) – 102 dB(A).
The NX contours for the current F-111 operations are shown in Figure 5-10, Figure 5-11 and Figure 5-12.
These figures show the band of buildings closest to the runways would experience close to 20 movements
above L(A)max 70 dB(A) and 10 to 15 movements above L(A)max 85 dB(A) due to the F-111 on an average
day. There would be less than 5 movements with L(A)max above 100 dB(A).
Change in Noise Environment Due to Super Hornet
The Super Hornet will increase aircraft noise within the Base. The L(A)max for the group of buildings adjacent
to the runway would increase to between 104 dB(A) – 117 dB(A) (highest values closest to the runways). The
group of buildings further west would experience a noise level in the range 96 dB(A) – 102 dB(A) similar to the
F-111 (but decreasing westwards rather than increasing as for the F-111).
As a result of the introduction of the Super Hornet, the buildings closest to the runways will experience 15 - 20
movements above L(A)max 100 dB(A) and close to 20 movements above L(A)max 85 dB(A). For the
buildings located in the western pocket of the Base, the current noise exposure due to the F-111 is less than 5
movements with L(A)max over 70 dB(A). With the Super Hornet, this would increase to 3 - 5 movements with
L(A)max above 100 dB(A) and 8 – 11 movements with L(A)max above 85 dB(A).
The buildings adjacent to the runways are currently subject to high levels of noise due to the F-111 and
workplace health and safety procedures are in place to manage working in this environment. With the Super
Hornet, the noise levels will be significantly higher, in the order of an increase of 15 dB(A). Given the existing
workplace procedures, the low number of movements in absolute terms and that the interruption to activities
may be only of the order of 30 – 90 seconds, the noise impact overall is assessed as manageable within
existing procedures.
On-Base noise levels are significantly influenced by aircraft at maximum power on the runway prior to takeoff.
L(A)max values calculated by the INM do not take into account the shielding effects of buildings.
Consequently, Defence has initiated a separate study of on-Base noise impacts. This study is examining
expected noise at several key locations on-Base, to assess the impact on everyday on-Base activities. It will
take into account building design and shielding effects. Defence and the RAAF will implement any
recommendations that come out of this study to ensure Defence meets its responsibility for the health and
safety of its personnel.
The potential impact of noise on the Amberley Childcare Centre is discussed at Section 5.6.4.2. L(A)max
contours for the Super Hornet and F-111 across areas on-Base, and close to the Base, are shown Figure
5-13 and Figure 5-14.
132
35 51
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LEGEND
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Childcare
Education
RAAF Base
Amberley
Super Hornet
L(A)max Contour
80
110
140
85
115
145
60
90
120
150
65
95
125
155
70
100
130
160
75
105
135
10
46
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AUSTRALIAN
SUPER HORNET
PER
FIGURE 5-13
Super Hornet L(A)max Contours
Close to Base Facilities
μ
Projection: WGS 84 - Zone 56
0
0.5
1
Kilometres
Scale 1:50,000 on A4
1.5
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I:\QENV\Projects\QE09512\Spatial\ArcGIS\Arc_MXD\Report_Figures\Figure_5-13_ASH_Lamax_Contours_Contours_Close_Base_Facilities_v3.mxd Produced: 3/8/2009
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Childcare
Education
RAAF Base
Amberley
F111 L(A)max
Contour
75
100
125
80
105
130
60
85
110
135
65
90
115
140
70
95
120
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AUSTRALIAN
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FIGURE 5-14
F-111 L(A)max Contours
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44
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5.5.2.
Ground Activities
There are two main ground activities associated with the Super Hornet:
1)
Engine running on flight line associated with maintenance activities – up to 95 events per year for 30
minutes, 80% of events will be between 7 am and 11 pm with 20% of events during the remaining hours
of the day; and
2)
High-power in-aircraft engine running at ETC 3 associated with maintenance activities – up to 12 events
per year for 30 minutes with all events before 11 pm. Currently the test cells are enclosed by a 3.5 m
concrete bund with a 3.5 m barrier on top, 7 m in total height. The existing 3.5 m barriers are faced with
absorptive treatment and perforated metal.
The F-111 aircraft currently uses ETC 3 once every 11 days for around 30 minutes. F-111 high-power engine
running results in noise levels of 55 to 60 dB(A) in the nearest residences in western Leichhardt.
The Super Hornet is louder than the F-111 at full power. Super Hornet will therefore increase noise from ETC
3 to up to 75 to 80 dB(A) in adjoining residential areas. However the Super Hornet engine is very reliable
compared to the F-111 engine, which will reduce the need to run engines on the ground. The Super Hornet is
expected to use ETC 3 only once a month and not between 11 pm and 7 am. Consequently, Super Hornet
high-power engine running is not expected to have a significant effect on the surrounding community.
The flight line area is more remote from residential areas than ETC 3. Additionally engines are run at lower
power settings in the flight line area. The noise levels at low power are similar between the Super Hornet and
the current F-111 engine runs. As the Super Hornet is a more reliable and newer aircraft, the RAAF expects
less need for engine running on the flight line compared to the F-111. Super Hornet engine running on the
flight line is not expected to cause a noticeable change in the noise environment.
5.5.3.
How Meteorological Conditions may affect Super Hornet Aircraft Noise
Prevailing winds will influence noise distribution – downwind is likely to receive higher noise levels than
predicted and upwind is likely to receive lower noise levels than predicted. In the case of the Super Hornet
flight paths from RAAF Base Amberley:
„
„
Spring, summer and autumn - areas to the west e.g. Walloon-Thagoona and Jeebropilly, may be subject
to increased noise levels and other areas e.g. Ipswich, reduced noise levels; and
Winter – areas to the south-east e.g. Yamanto, may be subject to increased noise levels and other areas
reduced noise levels.
Super Hornet flights climb away from the ground quicker and are planned not to follow low-level flight paths
around the Base. The effects of wind cannot be avoided; however, these measures will reduce potential
impacts to an extent.
135
Temperature inversions can occur in the area between 8 pm and midnight. Therefore noise from night flights
(Monday to Thursday) may be increased due to the temperature inversion effect. The majority of Super
Hornet night operations will be conducted between 8 pm and 10 pm and will in general avoid the most likely
period for stronger temperature inversions.
5.6. Potential Effects of Noise
This section examines the potential effects of the changes in noise levels identified in preceding sections.
The potential effects of high levels of aircraft noise on people include potential sleep disturbance,
cardiovascular and physiological effects, effects on communication (at home and at school), on sleep and
mental health, birth weight of babies and possibly mortality. The evidence from the studies does not provide
definitive answers. Many of these studies are short term rather than long term and while short term effects
may be established, the long term practical effects are unknown.
The New Parallel Runway Draft EIS undertaken for Brisbane Airport (BAC, 2007: D9 364), identified that
some groups within the community are more sensitive to high levels of aircraft noise than the general
population and subsequent effects such as sleep disturbance, annoyance and health effect. These include:
„
Shift workers and persons who sleep/rest during day time hours;
„
Young children;
„
School students; and
„
Elderly persons, including hospital and nursing home patients.
5.6.1.
Housing Values
There have been quite a number of studies conducted documenting the impact of noise on the cost of housing
nearby (Bateman et al, 2004, Nellthorp et al 2007). The factors influencing the selling price and selling time of
a house are (Nelson 2008):
„
House attributes;
„
Seller characteristics;
„
Seller strategies;
„
Bargaining strength;
„
Spatial competition; and
„
Temporal Factors – time of the sale and season of the sale.
Nelson (2008) reviewed studies about house values and noise levels around civilian airports, particularly in
regard to value changes as distance from an airport increases. The Noise Depreciation Index (NDI) is the
change in house value experienced as a result of an increase in noise level by one decibel. The NDI is
136
measured by comparison of houses at different locations around an airport at a given time. It is not derived
from how much house values change as a result of changes in noise over time.
Nelson established a mean NDI value of 0.92%, meaning a house exposed to one decibel more noise than
another equivalent house could be expected to be valued 0.92% less, and concluded that NDI values are
reasonably stable over time. The NDI has been applied to both airports and road traffic but has not been
applied to military airfields.
For areas around airports, it is unclear as to what extent the locational benefits, for example being close to
employment, positively affect house values (MVA Consultancy 2007).
Faburel (2005) identified that a stabilisation of noise exposure or even a reduction in levels is not necessarily
accompanied by a restoration of real estate values. This shows that the depreciation of property values is not
directly linked to the physical characteristics of the noise.
The baseline housing price data from the Real Estate Institute of Queensland in Table 4-11 provides an
indication of the house and vacant land pricing change for the area around the Base for the December
Quarter of 2008. The data is not consistent in terms of either aircraft noise exposure or in terms of direction
and degree of change. It can be seen that many factors apart from noise are an important determinant in the
final sale price. It is likely that other factors will dominate any movement in house price.
In summary, it is unlikely that the Super Hornet noise levels will directly affect house values in surrounding
areas as:
„
„
Existing changes to house values in areas around the Base vary widely showing that many factors affect
house values regardless of aircraft noise; and
Numerous other factors, such as economic conditions and changes in supply and demand for different
types of housing, have an effect on house values.
5.6.2.
Sleep Disturbance
Aircraft noise is more intermittent than other sources resulting in a greater potential for disturbance to sleep
patterns. Many sleep studies have been conducted in the field and in the laboratory and it was observed that
people respond to the maximum noise level during a nearby flight (Morrell, Taylor and Lyle 1997, PasschierVermeer 2003). Repeated sleep interference from aircraft noise may affect an individual’s health (Wyle 2003).
A study conducted by Lukas (1978, cited in Wyle 2003) indicated that some people are more sensitive to
noise during sleep, including older persons and women. The study also noted that there was a wide variation
in noise sensitivity in individuals.
137
Sleep disturbance is generally considered to be an issue during the night time but could also be a factor
during the day for shift workers. Noise may interfere with sleep in a number of ways including:
„
Awakening – it may cause a sleeper to awaken repeatedly resulting in poor sleep quality;
„
Alter sleep pattern – noise may cause sleep to change from heavier sleep to lighter sleep;
„
„
Reduction of the percentage and total time in REM (Rapid Eye Movement stage of sleep) sleep and may
result in increased body movement; and
Effects on slow wave sleep.
Sleep disruptions may cause fatigue, short term annoyance and changed mood that may lead to impaired
performance. Analysis of demographic data and Super Hornet noise contours indicates a potential for an
increase in interrupted sleep for a limited number of hours in the evenings from Monday to Thursday for
vulnerable groups.
The areas with the highest percentage of these groups are located to the east of the Base, while for Super
Hornet, most movements are planned for north, south and west of the Base.
The effect of aircraft noise appears to be related to both the maximum level and the number and duration of
the events. eNHealth 2004 concludes that for short term or transient noise events and for good sleep over
eight hours, the indoor sound pressure level should not exceed L(A)max 45 dB(A) more than 10 – 15 times
per night. The current Australian Standard AS2021-2000 recommends an indoor L(A)max of 50 dB(A) to avoid
sleep disturbance. In other words, outside noise levels greater than 55 dB(A) to 60 dB(A) may disturb sleep,
depending on whether windows are closed or not and the individual’s susceptibility to disturbance.
Night-time Super Hornet noise has the potential to disturb sleep. Figure 5-7 shows that a large area will be
exposed to several movements on an average flying day of greater than 70 dB(A). When night flying is
programmed, a proportion of these movements will be between 7 pm and 1 am. Night flying is, however, only
planned for Monday to Thursday nights and the majority of night flights will be between 8 pm and 10 pm. No
flights are planned between 1 am and 7 am Monday to Thursday, and no flights are planned for Friday,
Saturday or Sunday nights. Potential disturbances would be of short duration and would not persist through
the night. The ambient noise levels described in Section 5.4.1. show that in some locations, night-time noises
of over L(A)max 85 dB(A) due mainly to road or rail traffic, are occasionally already experienced.
Additionally, the F-111 currently spreads maximum noise levels of greater than L(A)max 85 dB(A) wider than
is forecast for the Super Hornet. In some locations, a decrease in maximum noise levels (particularly due to
the absence of night circuits over Ipswich) will be experienced, improving conditions for sleep.
Although for more sensitive people in certain locations the Super Hornet may have a negative impact on
sleep, overall a significant disruption to sleeping patterns is not expected.
138
5.6.3.
Shift Workers
The noise impact on shift workers will vary depending on:
„
The activity they are conducting at the time of a nearby aircraft flight, e.g. sleeping, relaxing, listening to
radio or watching TV;
„
Whether the aircraft is arriving, departing or conducting circuit training;
„
The type of house that the shift worker lives in;
„
Which room in the house they are in e.g. room with windows facing outdoors or inside the house; and
„
The number of aircraft flying past in the wave and which flight path is being used.
The highest proportion of shiftworkers is located to the east of the Base. Current F-111 movements occur to
the east of the Base and therefore could potentially affect sleeping shiftworkers located in this area. Super
Hornet movements are planned more to the west, north and south of the Base.
It is possible that some shift workers will be awoken from their sleep on occasion due to Super Hornet noise,
which could be a cause of annoyance, but this is also possible currently due to F-111 flights. The frequency of
disturbance is expected to be minor and no significant impacts are envisaged.
5.6.4.
Health
5.6.4.1.
Cardiovascular Impacts
Many studies have been conducted to investigate mean blood pressure, hypertension and heart disease.
There is evidence of an association with high levels of transportation noise (Morrell, Taylor and Lyle 1997,
Babisch 2005, 2006). More recently, Black et al (2007) concluded that long term aircraft noise exposure was
significantly associated with chronic noise stress and chronic noise stress was significantly associated with
the prevalence of hypertension i.e. high levels of aircraft noise have a health impact in terms of hypertension
and stress.
There are also a range of other factors that are directly and indirectly linked to cardiovascular health issues.
Communities surrounding the Base are currently subject to aircraft noise from F-111 movements. While the
number of movements will increase, the total number of movements, and therefore levels of aircraft noise, is
small in comparison to a major civilian airport. The change in noise levels due to the Super Hornet is unlikely
to be significant in regard to cardiovascular impacts.
139
5.6.4.2.
Children and Learning
In the last 20 years here has been increased empirical research investigating the effects of noise on children,
many of those focused on aircraft noise (US DOD, 2003, enHealth 2004). The evidence for the effects of high
levels of noise exposure on child health is strongest for cognitive effects, though these effects are not uniform.
Tasks which involve reading, attention, problem solving and memory appear to be most affected by high
levels of noise.
enHealth (2004) concluded that while there is sufficient evidence to support a conclusion that chronic noise
exposure at schools affects child health and performance, further data is required to provide guidance on the
noise threshold level. More recently, Eagen et al (2008) noted that high levels of aircraft noise interfered with
reading, motivation, language and speech acquisition and that learning decreases in reading when the
outdoor noise level exceeded L(A)eq5 65 dB 16 hours. As a result of the recognition that chronic exposure to
high aircraft noise levels may impair learning, WHO (2000) concluded that daycare centres and schools
should not be located near major sources of noise such as airports or highways.
Table 5-7 shows the L(A)max value at each of the schools and childcare centres close to the Base for both
the F111 (current) and the Super Hornet (future). For the Amberley State School and Amberley Community
Pre-School, the current value reflects their current locations and the future values the expected future
locations for these facilities. Apart from Amberley Childcare Centre (discussed separately), there is a
significant reduction in L(A)max values for educational facilities located near to RAAF Base Amberley.
„
Table 5-7 L(A)max Values for Schools and Childcare Facilities close to RAAF Base
Amberley
Site
F-111
Amberley State School
(Amberley Site)
87
0
87
+1
87
Amberley State School
(Yamanto Site)
Amberley Community PreSchool and Kindergarten
Association (Amberley Site)
Super Hornet
Change from F-111
to Super Hornet
L(A)max
86
Amberley Community PreSchool and Kindergarten
Association (Yamanto Site)
Amberley Childcare Centre
86
104
+18
West Moreton Anglican College
105
99
-6
West Moreton Anglican
Community Kindergarten
100
98
-2
5
L(A)eq is the equivalent continuous noise level i.e. it is the steady dB(A) level which would produce the same A weighted
sound energy over a stated period of time as the specified time-varying sound.
140
F-111
Super Hornet
Change from F-111
to Super Hornet
Leichhardt State School and
Prep year
102
88
- 14
Ipswich Early Education Centre
and Pre-School
102
88
- 14
Immaculate Heart School
100
88
- 12
Ally’s Kindy at One Mile
102
91
- 11
Site
L(A)max
It is important to consider the number of movements that may occur in addition to the maximum aircraft noise
level due to either F-111 or Super Hornet operations. Table 5-8 shows the N70, N85 and N100 for both the
F-111 and the Super Hornet at each of the educational facilities.
„
Table 5-8 NX Values for Schools and Childcare Facilities close to RAAF Base Amberley
Site
F111
Super Hornet
N70
N85
N100
N70
N85
N100
Amberley Childcare Centre
10
<5
0
>15
>15
8
West Moreton Anglican College
10
<5
1
>15
10
0
West Moreton Anglican
Community Kindergarten
9
<5
1
>15
10
0
Leichhardt State School and
Prep year
7
<5
1
>15
11
0
Ipswich Early Education Centre
and Pre-School
7
<5
1
>15
11
0
Immaculate Heart School
7
<5
1
>15
11
0
Ally’s Kindy at One Mile
8
<5
1
>15
13
0
While the number of Super Hornet movements will be greater than F-111 movements, they are relatively small
compared to major civilian airports. The operational profile has been designed to minimise noise impacts and,
in general, maximum noise levels will decrease from the current situation for schools. A noise level of L(A)max
85 dB(A) is the equivalent of a large truck driving into or past the school. Super Hornets will in most cases be
creating noise up to this level for a very short period of time, in the order of 30 to 90 seconds. Schools and
other educational facilities in the area surrounding the Base are currently affected by F-111 movements.
Educational facilities will not be greatly affected by changes in noise levels due to the Super Hornet and
therefore impacts on learning are not expected.
141
Amberley Childcare Centre
At the childcare centre on Base, there would be an increase of the number of movements with the increase in
noise level in the order of 20 dB(A) (perceived as approximately four times as loud as the F-111). This
increase is significant and momentary disruption in the class rooms may occur depending on the activity being
undertaken at the time. Although the maximum noise level increase is significant, the number of average
movements is low (8 per day, which will generally be gathered in 2-3 formations of 2-4 aircraft). Depending on
the current design of the Centre, additional noise mitigation may be required. Outdoors, noise exposure is not
sufficient to cause hearing impairment, just momentary distraction.
The Amberley Childcare Centre, located in a Defence-owned building, is included in the on-Base noise study
Defence is commissioning. This study will take into account the effects of building shielding and building
design on potential noise impacts. Defence will implement the recommendations of this study, including any
requirement for additional noise attenuation.
5.6.4.3.
Mortality
A number of studies of mortality rates around airports have been conducted and these show that there is no
strong or consistent correlation with aircraft noise (Morrell, Taylor and Lyle 1997). As for annoyance, any
effect is likely to be related to number of movements and also with the L(A)max level. Due the limited number
of Super Hornet movements and lack of a strong correlation between aircraft noise and mortality, it is not
expected that the Super Hornet will influence mortality in surrounding areas.
5.6.4.4.
Effect on Hearing
The current Queensland occupational noise criterion is Part 12 of the Workplace Health and Safety
Regulation 2008 (Qld) which states that the employer must prevent risks to the health and safety of workers
from exposure to excessive noise at work. Under the regulations, "excessive noise" includes an 8 hour
equivalent continuous A-weighted sound pressure level, L(A)eq of 85 dB(A), referenced to 20 micropascals.
The regulation applies to situations where people have unprotected ears and would apply to RAAF Base
Amberley employees.
The regulation can be applied to assess the risk of hearing damage to people exposed to high maximum
noise levels due to aircraft flying nearby. Residents living in areas near to the Base can be exposed up to
L(A)max 90 – 100 dB(A) outdoors during nearby aircraft flights. In particular, people in Purga or Wanora may
be exposed to a L(A)max of 90 dB(A) due to a Super Hornet operation. A wave of ten aircraft passing nearby
will have a total energy equivalent to less than 55 dB(A) which is much less than the noise exposure criterion
limit.
A laboratory study of military low-altitude flight noise identified that repeated exposure to a noise level of
greater than L(A)max 114 dB(A), especially if the noise increases rapidly, may cause noise induced hearing
loss (reported in US Department of the Navy 2003).
142
Figure 5-9 shows that the number of aircraft flights with levels in excess of L(A)max of 100 dB(A) are less
than 10 per day on average close to RAAF Base Amberley and even less further away. Given the limited
exposure to Super Hornet movements, no danger of hearing loss is expected.
5.6.4.5.
Overall Health Impacts
Morrell, Taylor and Lyle 1997 concluded that “While there is a lack of strong evidence supporting the
hypothesis that aircraft noise causes long term effects on health, not all the hypothesized health risks, such as
aspects of mental health and perinatal outcomes, have been studied in detail. Other effects, because of
possible long latency between exposure and manifestation, and because of difficulties in measuring exposure
and confounding variables, require large long term studies on populations in which individuals are followed
over an extended period under changing conditions of exposure.”
Based on this conclusion, the current occurrence of aircraft noise from F-111s and the limited number of
Super Hornet flights, there is insufficient evidence to link future health impacts to the operation of the Super
Hornet.
5.6.5.
Impact on Recreational Areas
People engaged in recreational activities such as camping or hiking may be “startled’ by the sudden
appearance of a Super Hornet as they might experience a sudden loud noise without visual or audible
warning. The likelihood of this occurring will be reduced with the introduction of the Super Hornet as it will not
fly at low levels in the vicinity of the Base as the F-111 currently does. In addition, recreational areas are
more often used on weekends and public holidays when the Super Hornet flights would generally not occur.
Furthermore, these areas are currently impacted by the F-111 and introduction of the Super Hornet will not
result in any significant changes, even with increased movement numbers.
5.6.6.
Impact of Aircraft Noise on Animals
Animal species exhibit a wide variety of responses to noise which are somewhat dependent on the type of
aircraft and the noise exposure. It is therefore difficult to generalise across animal responses as reactions
appear to be species specific.
It is recognised that hearing is critical to an animal’s ability to react and survive in its environment to avoid
predators, obtain food and communicate with and attract other members of their species. It has been found
that, in general, most animals are not particularly affected or that they habituate to increased noise levels.
The largest impact may come from a “startle” effect causing a flight response which could result in death or
injury and damage to fences when stock or animals react instinctively. Manci et al (1988) also reported that
avian species may be more sensitive than mammals.
143
Chapter 4 identifies that there are environmentally sensitive areas at and surrounding RAAF Base Amberley
and that there are some threatened species. These are all currently impacted by aircraft noise, in particular
by the current F-111 operations and they appear to exhibit a fair degree of habituation to aircraft noise. In
particular, these species include:
„
A population of koalas – koalas occur throughout the Base and surrounding areas within open eucalypt
woodland and riparian corridors of Warril Creek and Bremer River. They also occur within operational
areas immediately west of the flight line. Some of the koalas are exhibiting signs of chylamadia (due to
stress) though this is not necessarily noise related but rather due to a range of factors including
increases in construction surrounding the Base, traffic and people associated with construction activities;
„
A grey-headed flying-fox colony located at Woodend, 4 km north-east of the Base; and
„
Kangaroos on base.
As a result of current F-111 operations, some of the koala primary habitat areas would experience L(A)max
levels ranging from 85 to over 105 dB(A) (refer to Figure 4-13). The majority of the secondary habitat areas
experience L(A)max in the range 80 – 90 dB(A). With the introduction of the Super Hornet, the L(A)max level
would be in the range of 90 - 100 db(A). The majority of the secondary habitat areas would experience
LAmax in the range of 90 – 100 L(A)max. Generally the noise levels in the primary habitat areas will be
reduced while those in the secondary habitat areas will increase but still be less than the current worst case
exposure by the F-111. The koalas in the primary habitat areas are already subject to aircraft noise and
overall the situation will improve with the introduction of the Super Hornet.
Given the current noise environment due to the F-111 in particular, the introduction of the Super Hornet
should not result in a significant impact, even with increased movement numbers.
5.6.7.
Vibration
Aircraft noise has been known to cause windows and other household items to vibrate and rattle and this can
cause annoyance to occupants. There have also been claims of roof tile damage as a result of aircraft flights.
However, the possibility of structural damage is only likely if the sound level exceeds 130 dB(A) (von Gierke
and Ward 1991) and the sound level must last more than one second.
The British Standard BS 73 85-2:1993 notes that for transient vibration, cosmetic damage to residential
buildings needs to exceed 15 – 20 mm/s peak particle velocity. Given that typically the vibration level due to a
truck at 5 metres is less than 1 mm/s, the likelihood of structural damage due to a nearby aircraft flight is
negligible.
Although the risk of structural damage is extremely low, aircraft noise from Super Hornet operations may
cause vibration in windows and other household structures. The likelihood of this occurring increases with
L(A)max values above 90 dB(A), particularly at low frequencies experienced during aircraft take-off.
144
Figure 5-6 shows the areas where an L(A)max above 90 dB(A) may be expected. In general, this will be to
the north and south of the Base, including Ironbark, Wivenhoe Pocket, Mount Forbes, Peak Crossing and
Purga. Some of the nearest residences in Karrabin, Wulkuraka, Leichhardt, One Mile and Yamanto may also
be exposed to these sound levels.
While vibration may be experienced in buildings in these areas, it will only be of a short duration, in the order
of seconds, when noise levels of 90 dB(A) are expected. Additionally, the number of times this will occur per
flying day will on average be less than five.
5.6.8.
Summary of Potential Noise Impacts
The assessment indicates that it is unlikely that the Super Hornet movements will have a significant impact on
most people living in the areas surrounding the Base. This includes outdoor activities.
In summary, there is:
„
A high existing ambient noise level in some of the surrounding areas;
„
Existing military aircraft noise, particularly from the F-111;
„
An increase in the areas experiencing L(A)max in the range of 70 – 85 dB(A) (up to the equivalent of a
passing large truck) and an increase in the number of movements which create noise up to this level;
„
A relatively infrequent and small duration of exposure, limited to 30 to 90 seconds;
„
Relatively small movement numbers;
„
No movements from Friday night to Sunday night; and
„
Schools close to the Base will be subject to a greater number of movements though at a reduced
maximum noise level.
In regard to health impacts, impacts to hearing, mortality and cardiovascular disease are unlikely. Similarly,
interruption to indoor activities, including sleeping and educational activities, would generally be minimal apart
from occasional disturbance on infrequent occasions.
Structural impacts to buildings are not anticipated.
The Amberley Childcare Centre, located within the Base boundary, will be exposed to increased maximum
noise levels and movements. This may cause momentary disruptions inside. Depending on the design of the
Centre, noise insulation may be required.
Noise levels and movement numbers will increase on-Base which is a workplace health and safety issue.
Procedures are currently in place to manage aircraft noise. Defence will be undertaking a separate study to
assess on-Base noise issues, including for the Amberley Childcare Centre, and will be conducting a noise
audit once Super Hornet operations are underway. Defence will be implementing the recommendation of this
study.
145
Animals may be infrequently startled but should be relatively habitualised to aircraft noise.
5.7. How Super Hornet Noise Impacts are Mitigated
The RAAF will mitigate potential noise impacts from Super Hornet flying operations in three ways:
„
Modification of flight paths;
„
Modification of procedures; and
„
Continued communication with the public.
The following sections describe the flight path and procedural measures to limit noise impact already
incorporated in the design of Super Hornet flying operations. Also outlined are improvements to
communications the RAAF plans to implement to further mitigate potential environmental impacts. These
planned mitigations have been developed in consultation with members of the community around RAAF Base
Amberley.
In addition, Defence has recently installed a NFPMS at RAAF Base Amberley. This system will support review
of the proposed mitigation measures and communication of their effectiveness.
Defence does not believe offsets in the form of noise attenuation are necessary; however, they will be
considered if information comes to light indicating they are needed.
5.7.1.
Modification of Flight Paths
Planned Super Hornet flight paths are designed to avoid overflying Ipswich and other populated areas by
using existing arrival and departure corridors to the north and south of RAAF Base Amberley. The following
specific measures are planned to limit noise impact on the present and future community around the Base:
„
On departure, Super Hornet will climb as soon as possible above 15,000 ft (4,550 m);
„
Super Hornet circuits will be flown to the west of Runway 15/33, away from Ipswich;
„
Super Hornet will not use Runway 04/22 during normal operations;
„
Super Hornet will not turn left after take-off on Runway 15;
„
„
Left turn after take-off on Runway 33 will be delayed to minimise over-flight of Walloon and Thagoona;
and
Super Hornet will not normally conduct low level (less than 1,500 ft – 450 m) circuits, arrivals or
departures.
146
5.7.2.
Modification of Procedures
As well as designing where the Super Hornet will fly to minimise the potential effect of aircraft noise, the RAAF
has made changes to when and how the Super Hornet will operate. Procedural measures which limit
environmental impact are listed below:
„
„
„
„
Super Hornet operations include planned periods of respite from noise. In normal operations, Super
Hornet are not planned to fly on weekends. There will be breaks from Super Hornet flying at the Base of
two-three weeks in the middle of the year and three-four weeks over the Christmas period;
Super Hornet night flying will only be planned for Monday to Thursday nights. The majority of night flying
will be conducted between 8 pm and 10 pm. No repeated practice circuits will be flown between 11 pm
and 7 am. If aircraft are required to return to land after 11 pm, it will be via the straight-in approach
profile, which is less efficient but spreads aircraft noise less widely;
No Super Hornet high power ground engine running will be conducted at ETC 3 between 11 pm and
7 am; and
Where weather and operational requirements allow, take-offs will not use afterburner.
These requirements will be incorporated in Standard Operating Procedures for Super Hornet at RAAF Base
Amberley. These procedures have been designed to keep noise levels at or below those forecast in this
chapter. At times, Super Hornet flying operations may be conducted outside these limits, but that will be in
exceptional circumstances such as preparation for an operational mission.
5.7.3.
Communication
The RAAF recognises the vital importance of good communication to mitigation of potential environmental
impacts. It also recognises that communication with the community should be a continued focus for the RAAF
to ensure that future communication is achieved more effectively with the community.
5.7.3.1.
Community Consultative Meetings
While balancing open communication with operational security concerns, the RAAF has taken the Super
Hornet PER as an opportunity to reaffirm its commitment to effective community consultation. It has
established the Amberley Community Engagement Forum, a meeting of the Mayor of Ipswich and the Senior
Australian Defence Force Officer with other community leaders to discuss strategic issues concerning the
Base and the local region.
Under this higher-level forum, the RAAF has also established an Amberley Consultative Working Group. This
group brings community representatives together with Ipswich City Councillors, other local politicians and
Defence leaders from the Base to address topics involving the interaction between Amberley and the
community.
147
Both of these forums have met recently to discuss the Super Hornet PER and potential Super Hornet noise
effects. The discussion has been very positive and feedback received from these community leaders and
groups has been included in preparation of the Draft PER.
5.7.3.2.
Other Methods of Communication
Presently, the Base uses media releases and targeted letterbox drops to inform the community about
upcoming major events and potential disruption to members of the community.
The RAAF will continue to develop methods of communication to ensure its effectiveness. It is currently
investigating the following communication options:
„
„
Providing additional information on the RAAF Base Amberley page of the Defence website;
Sponsoring neighbourhood notice boards and signs, which will display information about upcoming
activities;
„
Reporting on flying activities monitored through the NFPMS (described in following section); and
„
Improved media releases and advertisements.
5.7.3.3.
Information to be Communicated
The types of Super Hornet flying information the RAAF will communicate include:
„
Periods of increased flying activity,
„
Periods of night flying,
„
Exercises, and
„
Flying activities which will be noticeably different from normal operations.
5.7.3.4.
Noise Complaints
The current system for registering a noise complaint will not change. Members of the public may call RAAF
Base Amberley at any time of the day on (07) 5461 1111 to register a noise complaint. Air Force staff treat all
community concerns seriously and with respect.
During working hours, questions regarding aircraft noise will be received by the Base Command Post.
Detailed information is taken from callers on the nature of the complaint, the exact location and the action
Defence is requested to take.
Base Command Post personnel are able to provide information on the types of flying being conducted from
the Base and the reasons for these operations. Generally, the provision of more information is sufficient to
address public concerns. In the case that further action is requested, the appropriate authority will be involved
with follow-up discussions with the caller.
148
Outside working hours, complaints are received by the Duty Member. The same detail will be recorded and
logged, although follow-up action is generally taken by knowledgeable staff the next day.
5.7.4.
Noise and Flight Path Monitoring System
In late 2008, Defence installed an NFPMS at RAAF Base Amberley. The objective of the Amberley NFPMS is
to demonstrate open and transparent environmental management through the evaluation of forecast flight
paths and noise levels and the communication of these forecasts to the community and other stakeholders.
Environmental Monitoring Units (EMUs) gather noise and weather data. Currently there are four fixed EMUs
on RAAF Base Amberley located at the ends of the runways. In the future, six relocatable EMUs will be added
to the system. These units will be placed at key locations in the communities around Amberley. Information
from the EMUs is collated with Air Traffic Control radar and flight data to give a complete picture of flight paths
(in three dimensions) and noise emissions. As the system is linked to the radar tracking system, it is capable
of identifying which aircraft are responsible for which noise level.
Defence is currently developing a suitable format for NFPMS reports. In the future, reports will be made
available to the ICC and the public. These reports will compare recorded flight paths and noise levels against
the forecasts in the PER. NFPMS reports will allow the public to assess whether the predicted noise levels are
actually being experienced around the Base. They will also provide information on reasons for deviation from
expected normal flying operations and an outline of the expected flying operations in the coming reporting
period.
In addition to providing valuable information to the public, NFPMS reports will allow the RAAF to assess the
effectiveness of the mitigation measures outlined above. RAAF will regularly review this effectiveness and will
consider further measures if required to address concerns about noise levels.
5.8. Options for Insulation of Houses
Although in general Super Hornet movements are not expected to have significant noise impacts on the
community, the PER Guidelines require discussion of insulating houses to reduce noise levels. This section
investigates the effectiveness, feasibility and indicative cost of installing noise insulation in a house or
community facility.
5.8.1.
Considerations for Insulating Houses
Insulating a house to reduce noise levels is only effective if windows and doors are closed and air conditioning
is installed and operating. Insulation measures need to be comprehensively provided to the roof, walls and
windows.
A house or building constructed of brick with a tile roof has better existing noise insulation than weatherboard
buildings with a corrugated iron roof.
149
A 15 dB(A) noise reduction is considered a reasonable practical limit on how much an existing house could be
acoustically upgraded at reasonable cost. To achieve greater noise reduction outcomes would require a
significant expenditure in comparison to the house value.
Noise insulation is likely to be less expensive for brick and tile houses where the desired noise reduction is
15 dB(A) or less.
5.8.2.
Insulation
Generic noise insulation for each of the two types of dwellings (brick and tile, weatherboard and iron) were
costed. Appendix I.6 shows the details of the assumed treatments. These included upgrading the roof area,
introduction of acoustic absorption into the ceiling void, upgrading of walls and glazing.
It is assumed that with glazing upgraded and sealed, the house would need to have air conditioning provided
(given the need for acoustic performance, passive cooling has not been considered.) Installation of air
conditioning would result in an increased electricity cost to the homeowner but there would be no direct
environmental costs. Increased electricity cost has not been included in the supply and install estimate.
5.8.3.
Single House (Brick or Weatherboard)
Table 5-9 shows the results obtained in terms of the supply and installation cost (excluding GST) for noise
insulation to achieve several noise reduction levels for the two types of dwellings. These cost estimates are
based on SKM/Rawlinson Australian Construction Handbook.
„
Table 5-9 Calculation of Estimated Material Costs
Noise Reduction
Residential Building Type
5 dB(A)
Weatherboard / Corrugated metal deck Roof
$37,950
Brick Veneer / Tile Roof
$25,150
10 dB(A)
15 dB(A)
Estimated Cost of Acoustic
Treatments per House
Weatherboard / Corrugated metal deck Roof
$89,260
Brick Veneer / Tile Roof
$70,700
Weatherboard / Corrugated metal deck Roof
$116,420
Brick Veneer / Tile Roof
$88,900
Assumptions: (1) Average house floor area – 200 m2 (2) Window area 25% of Floor area – 50 m2 (3) Wall area - 128 m2
Noise insulation is more effectively and cheaply incorporated at the planning and design stage. An indicative
extra cost to home builders for noise insulation and mitigation measures would be in the region of $500 $1,000/m2.
150
5.8.4.
Single Public Building
A similar costing exercise was conducted for the provision of insulation treatment to a community facility or
sports related venue.
The material and cost assumptions are shown in Appendix I.7. A key assumption was that the walls at these
facilities are masonry and that therefore there would not be any need for these walls to be acoustically
upgraded. In addition, it was assumed that a facility such as this would already have air conditioning.
Refer to Table 5-10 for costings.
„
Table 5-10 Calculation of Estimated Material Costs
Noise Reduction to
meet AS2021 criteria.
Building
Estimated
Building Area
Estimated Cost
for Acoustic
Treatments per
Facility ($K)
Childcare
200 m2
$20
Sport, Recreation, Leisure and
Cultural Facility
400 m2 (Club
Room)
$40
Childcare
200 m2
5 dB(A)
$65
10 dB(A)
15 dB(A)
5.8.5.
151
2
Sport, Recreation, Leisure and
Cultural Facility
400 m (Club
Room)
$130
Childcare
200 m2
$84
Sport, Recreation, Leisure and
Cultural Facility
400 m2 (Club
Room)
$170
Discussion
Noise insulation does not appear warranted by the anticipated change in aircraft noise as a result of the
introduction of the Super Hornet. The relatively infrequent noise events, the planned periods of respite from
aircraft noise and the small increase over ambient noise levels mean that any benefit from insulation to reduce
Super Hornet noise would be minimal. The cost incurred would not be justified in comparison to the minimal
benefit.
Additionally effective noise insulation requires sealing of a building from outside airflows and necessitates the
provision of mechanical ventilation and air conditioning. This is inconsistent with a preference for outdoor
living.
Finally, noise insulation of a building will not have any impact on noise levels experienced while outside.
5.9. Land Use Planning Implications
5.9.1.
Australian Noise Exposure Forecast
The ANEF (Australian Noise Exposure Forecast) system is the usual descriptor for land use planning in the
vicinity of airports in Australia as per Australian Standard AS2021 – 2000. The ANEF system is a measure of
cumulative aircraft noise over an average day taking into account the level of the individual aircraft noise,
tonal and duration changes, and the number of each aircraft type.
The ANEF system is not used to regulate aircraft operations but rather to report on the effects of those
activities. It is intended to guide future land use planning within the vicinity of airports and designated flight
paths, so that future development is not affected by noise.
The ANEF system has not proved to be most useful tool for explaining the likely impacts of aircraft noise to
the community. Being in an area of low ANEF value, or outside the contour area, does not mean an absence
of aircraft noise. Equally being inside the ANEF contours does not necessarily mean there is sufficient noise
to disturb residents. The Guidance Material for Selecting and Providing Aircraft Noise Information (DOTARS,
2003) advises that, ‘land use planning contours such as ANEFs are not considered suitable for use as an
aircraft noise information tool’. For this reason, this PER has provided several other methods of describing the
potential noise effect of the introduction of the Super Hornet.
Each civil aerodrome or military airfield has one published ANEF map at any one time. In military use, ANEF
maps generally have a ten year timeframe.
An Australian Noise Exposure Concept (ANEC) map is used as a planning tool to investigate likely changes to
aircraft noise exposure resulting from proposed changes to conditions at an airport. It shows what the ANEF
map would look like under a future scenario. An ANEC map does not have the legal standing for land use
planning an ANEF map does.
An ANEF map is normally presented as a series of noise contours on a map showing the area around an
airport that is potentially affected by aircraft noise. The ANEF levels are represented by a series of contours
joining all the points which have the same specified ANEF value e.g. 20, 25, 30 ANEF. The 20 ANEF value is
considered the level at which cumulative aircraft noise impacts begin having implications for land use
planning. The actual location of the 20 ANEF contour is difficult to define accurately, mainly because of
variations in aircraft flight paths, pilot operating techniques and meteorological conditions and is therefore
presented on these maps as a dotted line. Note that in areas outside the 20 ANEF contour, aircraft noise can
still be audible. However, the audibility will be dependent on the existing ambient noise in the area. The
ANEF system does not take into consideration ambient noise.
Apart from the number of aircraft, the runway used and the time of day, the shape and size of the resultant
ANEF contours are affected by:
152
„
„
„
The aircraft noise signature: each type and model of aircraft emits a different noise pattern;
Flight path and operation: the allocation of aircraft movements to flight paths and the type of operation
i.e. arrival, departure, touch and go or circuit, and time of day; and
The flight profile used when operating to and from an airfield: flight profiles characterise the aircraft
altitude (feet), its speed (knots) and thrust setting (percentage of maximum thrust) at a certain distance
from the runway (nautical miles).
The Australian Standard AS2021-2000 provides guidance to regional or local authorities and others
associated with urban and regional planning and building construction, on the acceptable location of new
buildings in relation to aircraft noise. Zones that are described as ‘conditionally acceptable’ may be approved
as building sites provided that any new construction incorporates sound proofing measures. Section 2 of the
Standard gives guidelines for determining the acoustic acceptability of a particular site.
Table 5-11 shows the recommended land use compatibility from Australian Standard AS2021. For land within
the 20 – 25 ANEF, AS2021 2000 advises that it is not compatible with residential or educational uses. In that
case, AS2021 states that land use authorities might consider that “the incorporation of noise control features
in the construction of residences or schools is appropriate”. In terms of planning, it can be seen that
residential/educational type uses are not recommended for land within ANEF 25.
„
Table 5-11 AS2021 Building Site Acceptability Based on ANEF Zones
Building Type
153
ANEF Zone of Site
Acceptable
Conditional
Unacceptable
House, home unit, flat,
caravan park
Less than 20 ANEF
20 to 25 ANEF
Greater than 25 ANEF
Hotel, motel, hostel
Less than 25 ANEF
25 to 30 ANEF
Greater than 30 ANEF
School, university
Less than 20 ANEF
20 to 25 ANEF
Greater than 25 ANEF
Hospital, nursing home
Less than 20 ANEF
20 to 25 ANEF
Greater than 25 ANEF
Public building
Less than 20 ANEF
20 to 30 ANEF
Greater than 30 ANEF
Commercial building
Less than 25 ANEF
25 to 35 ANEF
Greater than 35 ANEF
Light industrial
Less than 30 ANEF
30 to 40 ANEF
Greater than 40 ANEF
Other industrial
Acceptable in all ANEF zones
5.9.1.1.
Limitations for Application to Military Airfields
The ANEF system is primarily applicable to civilian aerodromes where numerous flights occur frequently every
day and throughout the year. RAAF airfields differ from civilian aerodromes as flights are not as frequent and
do not occur every day of the year. Furthermore, the operations of military aircraft can be managed, such as
planned for the Super Hornet, to not occur at sensitive times such as weekends and public holidays.
The ANEF system does not take into account the measures to manage military flying operations and depicts
cumulative noise impacts on an average flying day. To adequately describe potential noise impacts,
descriptors such as L(A)max and NX contours, as already discussed, are more appropriate.
The ANEF system is designed to guide future land use planning decisions rather than act as a description of
noise impacts.
5.9.1.2.
RAAF Base Amberley 2006 ANEF
The existing ANEF map for RAAF Base Amberley is titled the 2006 ANEF and is shown in Figure 5-15. The
RAAF Amberley 2006 ANEF map was released by Defence in July 1998 and is the approved baseline for land
use planning by Ipswich City Council in accordance with State Planning Policy 1/02.
5.9.1.3.
RAAF Base Amberley 2018 ANEC
Defence has prepared a 2018 ANEC map to show the modelled estimate of the future noise contours for
RAAF Base Amberley. It represents the expected cumulative noise impact (as depicted by the ANEF system)
of all aircraft planned to operate at the Base in 2018, including the Super Hornet. The 2018 ANEC map is
shown in Figure 5-16.
Following the finalisation of the Super Hornet PER and confirmation of Super Hornet operations, the 2018
ANEC will be converted to an ANEF for RAAF Base Amberley by Defence. Defence will engage an
independent consultant to validate the methodology used for the production of the ANEF.
154
20
20
25
40
20
30
25
RAAF Base Amberley
2006 ANEF Contour
20
25 - 40
AUSTRALIAN
SUPER HORNET
PER
FIGURE 5-15
μ
Projection: WGS 84 - Zone 56
0
2006 ANEF Contours
1
2
3
Kilometres
Scale 1:125,000 on A4
4
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35
LEGEND
5.9.2.
2018 ANEC versus 2006 ANEF
The change in average cumulative noise exposure from the 2006 ANEF map to the 2018 ANEC map for
RAAF Base Amberley can be seen in Figure 5-17. The area within the 2018 20 ANEC contour is increased
compared to the 2006 20 ANEF contour, particularly to the west and south of the Base. Areas which will have
changed in relation to both the 20 contours are:
„
Newly included in the contour are parts of Goolman and Walloon;
„
There is a reduction in part of Purga;
„
There is a reduction in the area of Ironbark;
„
There is an increase in the area of Pine Mountain; and
„
There is also a slight increase in the area covered out to the east at Churchill, Leichhardt and West
Ipswich.
This change in the shape of the contours is mainly, but not solely, due to the impact of the Super Hornet
arrivals and departures on Runway 15/33 as well as the Super Hornet training circuits being directed away
from Ipswich. The “horns” appearing at both ends of Runway 04/22 are due to C-17 circuits.
5.9.2.1.
Sensitive Receivers
The locations of sensitive receivers relative to the 2018 ANEC contours are shown by Figure 5-18. A majority
of these receivers fall within the 20 – 25 2018 ANEC contours though some fall within higher noise contour
areas. The location of these facilities relative to the 2006 ANEF contours is shown in Figure 5-19.
Table 5-12 identifies where the locations of sensitive receivers have changed in regard to the 2006 ANEF and
2018 ANEC contours. The table also documents the facilities that that fall within the 2018 ANEC contour, that
were not previously within the 2006 ANEF contours.
156
25
20
30
55
50
40
25
30
20
40
45
35
25
20
RAAF Base Amberley
2018 ANEC Contour
20
25 - 55
AUSTRALIAN
SUPER HORNET
PER
FIGURE 5-16
μ
Projection: WGS 84 - Zone 56
0
2018 ANEC Contours
1
2
3
Kilometres
Scale 1:125,000 on A4
4
I:\QENV\Projects\QE09512\Spatial\ArcGIS\Arc_MXD\Report_Figures\Figure_5-11_2018_ANEC_v2.mxd Produced: 8/7/2009.
30
LEGEND
20
25
20
25
20
30
30
25
20
40
55
35
35
45
40
30
30
20
25
20
LEGEND
RAAF Base Amberley 2006 ANEF Contour
20
25 - 40
2018 ANEC Contour
20
25 - 55
AUSTRALIAN
SUPER HORNET
PER
FIGURE 5-17
μ
Projection: WGS 84 - Zone 56
0
2006 ANEF / 2018 ANEC Change
1
2
3
Kilometres
Scale 1:115,000 on A4
4
I:\QENV\Projects\QE09512\Spatial\ArcGIS\Arc_MXD\Report_Figures\Figure_5-12_2006_ANEF_2018_ANEC_Change_v3.mxd Produced: 9/7/2009
50
35
40
25
0
35 3
40
35
30
35
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Accomodation
(
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Aged Care &
Retirement Facility
(
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Boarding Kennel
(
!
Cemetery
(
!
Childcare
(
!
Community Facilities
(
!
Education
(
!
Health, Police,
Emergency Services
(
!
Parks and Reserves
(
!
Places of Worship
(
!
Shopping Centre
(
!
Sport, Recreation, Leisure
and Cultural Facilities
(
!
Veterinary Clinics
LEGEND
2018 ANEC Contour
20
25 - 55
82
( (
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72
44
105
Inset B
AUSTRALIAN
SUPER HORNET
PER
FIGURE 5-18
Sensitive Receivers
ANEC 2018
μ
Projection: WGS 84 - Zone 56
0
0.9
1.8
2.7
Kilometres
Scale 1:75,000 on A3
3.6
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10
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(
!
Accomodation
(
!
Aged Care &
Retirement Facility
(
!
Boarding Kennel
(
!
Cemetery
(
!
Childcare
(
!
Community Facilities
(
!
Education
(
!
Health, Police,
Emergency Services
(
!
Parks and Reserves
(
!
Places of Worship
(
!
Shopping Centre
(
!
Sport, Recreation, Leisure
and Cultural Facilities
(
!
Veterinary Clinics
LEGEND
2006 ANEF Contour
20
25 - 40
11
48
99
(
! !
( (
111!
(
!
93
58
(
!
(
!
18
72
(
!
(
!
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105
(
!
Inset B
AUSTRALIAN
SUPER HORNET
PER
FIGURE 5-19
Sensitive Receivers
ANEF 2006
μ
Projection: WGS 84 - Zone 56
0
0.9
1.8
2.7
Kilometres
Scale 1:75,000 on A3
3.6
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(
!
83
98
Table 5-12 Sensitive Receivers within the 2006 ANEF and 2018 ANEC
Health, Police and Emergency Services
Flinders Peak Medical Centre
Ipswich Police Station (Police Beat)
Aged Care and Retirement Facilities
Gainsborough Downs Retirement Village
Palm Meadows Village
Childcare
Ally's Kindy At One Mile
Amberley Childcare Centre
Amberley Community PreSchool & Kindergarten Assoc. (Moving)
ABC Yamanto
Ipswich Early Education Centre & Preschool
One Mile Community Child Care Centre
Sunkids Children's Centre
Community Facilities
Amberley Girl Guides (Moving to site in Willowbank)
Amberley Playgroup (Moving to new site, yet to be determined)
Amberley Toy Library (Moving to new site in Ipswich)
Denman Street Youth and Education Centre
Leichhardt One Mile Community Centre
Places of Worship
Churches of Christ Leichhardt
Grace Baptist Church
Accommodation
Amberley Caravan Park
Willowbank Caravan Park
Willowbank Motel
Sport, Recreation, Leisure and Cultural Facilities
Active Golf Driving Range
Amberley RAAF Base Bowls Club
Jack Haggartey Shooting Complex
Ipswich Go Golfing Par 3 Course
Ipswich & West Moreton Tennis Association
Leichhardt Golf Course
Swifts Rugby League Football Club
Parks and Reserves
Bremerdale Park
Heit Park
Wulkuraka Park
Veterinary Surgery
Yamanto Veterinary Surgery
Cemetery
Warrill Park Land Cemetery
Boarding Kennel
Imparra Pet Motel
Shopping Centre
Yamanto Shopping Village
35-40
30-35
25-30
20-25
2018 ANEF
40-45
35-40
30-35
Name
2006 ANEF
20-25
Sensitive Receiver Comparison
25-30
„
161
The schools will not be changing their noise contour category. However, Ally’s Kindy at One Mile will have an
increased noise exposure in moving into the 25 – 30 2018 ANEC contour. This impact is due to C-17
operations and is not a result of the introduction of the Super Hornet.
Defence has included the Amberley Childcare Centre in its study of on-base noise impacts, as discussed in
Section 5.5.1.6. While Table 5-13 indicates there is an issue to be quantified, the ANEF system is not suited
to assessment of noise impacts for buildings located on an airfield. The separate study is taking into account
building location, current insulation measures and the effect of shielding by other buildings. In accordance with
its responsibilities towards its members and their families, Defence will implement the recommendations of
this study
Community facilities, places of worship and caravan parks are only located in the 20 to 25 contours. The
sports, recreation and leisure facilities will generally be in the same contours to that currently, with only a few
moving to higher contours. These land uses are predominantly used on weekends when there are to be no
Super Hornet operations.
Table 5-13 provides a sensitive receiver category summary for the 2006 ANEF and 2018 ANEC. A
summation of the sensitive receivers that appear in the 2018 ANEC is also provided.
„
Table 5-13 Sensitive Receiver Category Summary 2006 ANEF, 2018 ANEC
No. of new
facilities within
2018 ANEC1
RAAF Base Amberley Sensitive Receiver
Summary
2006
ANEF
Type
Total
Total
Total
Health, Police and Emergency Services
2
1
1
Education
4
4
0
Aged Care and Retirement Facilities
1
1
1
Childcare
4
7
4
Community Facilities
4
3
2
Places of Worship
2
4
2
Accommodation
0
3
3
Sport, Recreation, Leisure and Cultural Facilities
7
8
2
Parks and Reserves
4
4
0
Veterinary Clinics
0
1
1
Cemetery
0
1
1
Boarding Kennel
3
3
0
Shopping Centre
1
1
0
Total
32
41
17
1
2018 ANEC
Where new facilities exceed the difference between the total facilities identified in the 2006 ANEF and 2018 ANEC, it is
likely that facilities that were originally identified in the 2006 ANEF are no longer located within the 2018 contours.
162
The number of facilities within the 20 – 25 zone will increase but this is generally compliant with the building
acceptability standards. A more comprehensive description of potential noise impacts may be found in
Section 5.4.
5.9.2.2. Population Change in Contours
The population change from the 2006 ANEF contours to the 2018 ANEC contours for RAAF Base Amberley
has been calculated by multiplying the average number of persons per household by the number of residential
property lots within each of the contours. The average persons per household were determined for the
Ipswich LGA area (2.8) as of the 2006 Census.
Table 5-13 shows that the number of people within the 20 - 25 contour will increase significantly by 2018.
The biggest increases predicted, percentage wise, are for the number of people that will be within the 25 – 30
2018 ANEC contour and 30 – 35 2018 ANEC contour. In absolute terms, the biggest increase is in the 20 –
25 2018 ANEC contour.
„
Table 5-14 Comparison of Estimated Residential Properties and Population Count (2009)
2006
2018
ANEF/A
NEC
Number of Residential
Properties
Estimated
Population
Number of
Residential
Properties
Estimated
Population
20-25
4,686
13,121
6,897
19,312
6,451
25-30
484
1,355
2,304
30-35
114
319
420
1,176
35-40
33
92
110
308
40-45
9
25
44
123
16
45
9,791
27,415
45-50
Total
5,326
14,913
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5.9.2.3. Implications for Land Use and Development – Ipswich City Council
As discussed in Section 4.1, a significant challenge for the future development and operations at RAAF Base
Amberley is urban encroachment and/or incompatible development.
Existing and proposed industrial areas to the west of RAAF Base Amberley are going to be included within the
20 - 25 contour. New residential areas in Yamanto would also be included within the 20 contour
(development areas are shown in Figure 5-20).
For example, residential developments on the western side of Yamanto of Rangeview Estate would be within
this contour. Other residential areas previously below 25 2006 ANEF contour, would also fall into the above
25 2018 ANEC contour. In accordance with AS2021, new residential areas, schools or hospital sites are
considered “unacceptable” in this zone.
The areas within the 25 and 30 contours are expanded to the north, south and west of RAAF Base Amberley
reflecting the arrival and departure operations on Runways 15/33 and also the training circuits out to the west
rather than to the east. In accordance with AS2021, new residential and community developments within
these areas should be limited or not occur.
While changes in the increase in the 25 – 30 ANEF contours may restrict residential and community
developments, other uses are acceptable in these areas. Commercial and industrial buildings may be built in
these areas.
Once the 2018 ANEC map is converted into an ANEF map, under SPP 1/02, it will replace the 2006 ANEF
map in providing guidance for future land development around the Base. Ipswich City Council will be required
to use the 2018 ANEF in development assessment to ensure the appropriate location of different land uses as
well as the incorporation of appropriate noise mitigation measures during construction. The 2018 ANEF will
need to be incorporated into the planning scheme either through a planning scheme amendment or through a
future planning scheme review. The ANEF will influence planning for additional future development areas.
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20
Wulkuraka / Karabin
Industiral
20
Residential development
(57 dwellings)
25
Walloon-Thagoona
Master Plan Area
25
20
30
30
Residential development
(141 dwellings)
25
20
Townhouse Development
Residential subdivision (160 lots)
30
UQ Health & Education
training facility
35
Major Centre development
Industrial / Commercial
40
55
35
35
4
35 0 40
45
Yamanto TOD
(70 dwellings/ha)
45
Business / Industry
40
30
Yamanto Primary
30
Approvals -Residential
(20 dwelling/ha)
Residential
25
Ripley Valley
Purga industrial
development area
20
Ebenezer Heavy & difficult to locate
industrial development
20
LEGEND
Proposed New Rail Corridor
RAAF Base Amberley
2006 ANEF Contour
20
Development Area
25 - 40
Walloon-Thagoona Master Plan 2018 ANEC Contour
Ipswich Cadastre
20
25 - 55
AUSTRALIAN
SUPER HORNET
PER
FIGURE 5-20
Impact on Future Development Areas
(2006 ANEF & 2018 ANEC)
Projection: WGS 84 - Zone 56
0
1
2
3
Kilometres
Scale 1:115,000 on A4
4
I:\QENV\Projects\QE09512\Spatial\ArcGIS\Arc_MXD\Report_Figures\Figure_5-20_Impact_on_Development_Areas_v4.mxd Produced: 28/7/2009
30
40
50
35
40
40
25
40
35
40
Currently developing residential
40 35 35
5.10.
Government Policy on Attenuation and Compulsory Acquisition
Section 10 of the National Aviation Policy Green Paper released in December 2008, refers to previous
Government insulation programs around Sydney and Adelaide airports, where attenuation was provided for:
„
Residences within the 30 ANEF contour; and
„
Public buildings within the 25 ANEF contour.
These attenuation programs applied to areas impacted by frequent and persistent civilian airliner movements
and were substantially paid for through levies on ticket prices. Although the Green Paper states that “the
government will consider such programs for any airport should they become exposed to similar noise levels
through an increase in air traffic”, this policy is relevant for civilian airports only and is not applicable to RAAF
Base Amberley and other military airfields.
The Green Paper also recognises that ‘programs to address noise issues need to be tailored to the specific
characteristics of each airport, to meet the airport’s requirements and the aspirations of the communities
involved.’ While RAAF Base Amberley is a military airfield, rather than an airport, these considerations apply.
The RAAF has other mitigation options, more appropriate than noise attenuation programs, available to it
such as planned respite periods and modification of flight paths and procedures. The marginal benefit of noise
insulation does not appear warranted to manage the expected change in aircraft noise levels.
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Government has also in the past compulsorily acquired residences within the 40 ANEF contour around
airports. Again, this was done in areas exposed to the continuous and intrusive noise of repeated airliner
movements. Such a program is not appropriate for the type of noise exposure likely around RAAF Base
Amberley.
Defence does not provide noise attenuation for residences potentially affected by aircraft noise around its
airfields nor has it compulsorily acquired any of these residences. The analysis of the potential impact of the
introduction of the Super Hornet does not justify any change in this approach at RAAF Base Amberley. The
RAAF has already implemented more suitable mitigation measures and will monitor their effectiveness
through consultation with the community and the NFPMS.
5.11.
Summary
The assessment indicates that it is unlikely that the Super Hornet movements will have a significant impact on
most people living in the areas surrounding that Base.
Aircraft noise is an unavoidable consequence of vital Defence operations at RAAF Base Amberley. Currently,
F-111 and C-17 aircraft operate from RAAF Base Amberley so there is existing aircraft noise, although the
recent decline in F-111 movements at the Base is likely to highlight the change in noise as a result of the
introduction of the Super Hornet.
Defence has developed the flying operations of the Super Hornet to minimise potential noise impacts while
meeting operational requirements. Arrivals and departures will be undertaken to the north and south of the
Base and circuits to the west, away from the Ipswich urban area. Furthermore, no movements are proposed
between Friday night and Sunday night so no aircraft noise will occur on weekends. There are planned
periods of respite from aircraft noise in the middle and at the end of each year.
The Super Hornet will have a greater noise impact that the F-111. As a result of the introduction of the Super
Hornet, more people around RAAF Base Amberley will be exposed to aircraft noise likely to be noticeable (in
the range of L(A)max 70 dB(A) to 85 dB(A)). Noise up to this level is equivalent to a large truck passing by.
The decision to reduce the number of Super Hornet flight paths compared to the current F-111 operations
has, however, significantly reduced the potential number of people and sensitive receivers exposed to
maximum noise levels above 85 dB(A). Noise at these levels is more likely to be intrusive or disturbing.
While there will be an increase in movements, Super Hornets will generally be grouped into formations of two
to four aircraft, which will reduce the total number of noise events experienced per day. Additionally, maximum
noise levels will only be experienced for short periods of time, over 30 to 90 seconds. Over this time, the noise
level will gradually increase to a peak equivalent to the L(A)max value and then decline as the aircraft flies
away from the receiver.
The Super Hornet will increase aircraft noise over RAAF Base Amberley itself. Defence has initiated a
separate study of on-Base noise impacts. This study is examining expected noise at several key locations on
Base, to assess the impact on everyday on-Base activities. It will take into account building design and
shielding effects. Defence and the RAAF will implement any recommendations that come out of this study to
ensure Defence meets its responsibility for the health and safety of its personnel.
The Amberley Childcare Centre, located within the Base boundary, will be exposed to increased maximum
noise levels and movements. This may cause momentary disruptions inside. Depending on the design of the
Centre, noise insulation may be required. Defence has included the Centre in a study of on-Base noise and
will implement the recommendations of this study.
167
In summary, there is:
„
A high existing ambient noise level in some of the surrounding areas;
„
Existing military aircraft noise, particularly from the F-111;
„
An increase in the areas experiencing L(A)max in the range of 70 – 85 dB(A) (up to the equivalent of a
passing large truck) and an increase in the number of movements which create noise up to this level;
„
A relatively infrequent and small duration of exposure, limited to 30 to 90 seconds;
„
Relatively small movement numbers;
„
No movements from Friday night to Sunday night; and
„
Schools close to the Base will be subject to a greater number of movements though at a reduced
maximum noise level.
Due to these factors, significant impacts to health, outdoor activities, indoor activities, education and buildings
are not expected. Impacts to animals are also unlikely to be significant given the current aircraft noise and
ambient noise levels.
Defence has already implemented the following mitigation measures, developed in consultation with the
community around RAAF Base Amberley, in the design of Super Hornet flying operations:
„
„
„
Flight paths – modifications to minimise impacts on Ipswich and other urban areas;
Procedural modifications – to provide respite from aircraft noise on weekends, Christmas and the middle
of the year; and
Communication – Defence has established the Amberley Community Engagement Forum and Amberley
Consultative Working Group to discuss key issues, including the Draft PER with community
stakeholders.
The NFPMS has been recently established at RAAF Base Amberley to provide information on the actual
number of flights and the levels of aircraft noise. This information will be able to be compared to the predicted
noise levels for the Super Hornet contained within the Final PER.
Following the commencement of the Super Hornet flying operations, Defence will undertake ongoing
communication with the public. This is to ensure open and transparent consultation with the community, so it
is informed of flying operations from the Base and has the ability to identify concerns if they arise. Results of
the NFPMS will be available as part of this ongoing communication.
The 2018 ANEC map, which includes the Super Hornet operations, will replace the 2006 ANEC map once
Super Hornet operations are approved. The ANEC map is used to manage future development to minimise
conflicts. Some identified future development areas are included within the 2018 ANEC contours which means
the Ipswich City Council will need to consider the impact of changes in ANEF on its planning scheme.
168