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Aircraft Noise


Methodology Adopted for Assessing Aircraft Noise Impact

1. Throughout the new airport master planning process, the Airport Authority in conjunction with the government have conducted assessments to determine the effects of aircraft noise impacts on off-airport areas. The noise impact assessment was conducted in accordance with the guidelines set out by the International Civil Aviation Organization (ICAO) and the Federal Aviation Administration (FAA) of the United States Department of Transport. The FAA's Integrated Noise Model (INM) which is considered a state-of-the-art tool for assessing airport noise exposure, was used to generate noise contours.

2. The noise impact arising from aircraft operation can be represented by the Noise Exposure Forecast (NEF), a criterion which takes into account the duration of flyover, the peak noise level, the tonal characteristics and the number of aircraft movements in both the daytime and night-time period. For the new airport at Chek Lap Kok, the Hong Kong Planning Standards and Guidelines stipulate a more stringent criterion of NEF 25 contour (as against NEF 30 for Kai Tak Airport) for planning of noise sensitive land uses. This criterion is in line with the international standards adopted by the developed countries.

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Results of Aircraft Noise Impact Assessment

3. According to the New Airport Master Plan – Environmental Impact Assessment (NAMP-EIA) completed by the Airport Authority in 1991, its Supplement in 1992 and its Update completed in 1998, only a very small number of residents in North Lantau, predominantly in Sha Lo Wan, are within the coverage of the NEF 25 contour of the new airport at design capacity and regarded as subject to aircraft noise beyond acceptable level from a planning and land use point of view.

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Measured Noise Levels

4. CAD has conducted noise measurements in several districts under the flight paths. The measured noise levels are summarised in the table below:-

Measured Noise Levels at Various Districts
(1 July 2015 - 30 June 2016)

 
Distribution of Noise Levels
Mainly affected by Operation
(Runway/Operation)
Lmax (Note 1)
<65 dB(A)
65–69.9 dB(A)
70–74.9 dB(A)
≧75 dB(A)
Sha Lo Wan
77.6%
12.9%
8.1%
1.5%
07R,07L,25R,25L/Arrival (Note 2)
07R,07L,25R.25L/Departure (Note 3)
Tung Chung
84.8%
13.2%
1.9%
0.1%
07R,07L,25R,25L/Arrival (Note 2)
07R,07L,25R.25L/Departure (Note 3)
Sunny Bay
81.7%
16.3%
1.9%
0.1%
25R,25L/Arrival (Note 2)
07R,07L/Departure (Note 3)
Ma Wan
78.9%
16.8%
3.7%
0.6%
25R,25L/Arrival (Note 2)
07R,07L/Departure (Note 3)
Tai Lam Chung
96.6%
3.1%
0.2%
0.0%
25R,25L/Arrival (Note 2)
07R,07L/Departure (Note 3)
Tsing Lung Tau
82.1%
9.2%
8.0%
0.6%
25R,25L/Arrival (Note 2)
07R,07L/Departure (Note 3)
Ting Kau
84.0%
9.6%
6.2%
0.2%
25R,25L/Arrival (Note 2)
07R,07L/Departure (Note 3)
Tsuen Wan
86.1%
9.6%
4.2%
0.1%
25R,25L/Arrival (Note 2)
07R,07L/Departure (Note 3)
Tsing Yi #1
98.6%
1.0%
0.4%
0.0%
25R,25L/Arrival (Note 2)
07R,07L/Departure (Note 3)
Tsing Yi #2
99.1%
0.8%
0.1%
0.0%
25R,25L/Arrival (Note 2)
07R,07L/Departure (Note 3)
Kwai Chung
98.8%
0.9%
0.2%
0.0%
25R,25L/Arrival (Note 2)
07R,07L/Departure (Note 3)
Tai Wai
99.3%
0.7%
0.0%
0.0%
25R,25L/Arrival (Note 2)
Mid-Levels
98.4%
1.5%
0.1%
0.0%
07R,07L/Departure (Note 3)
North Point
96.8%
2.7%
0.4%
0.0%
07R,07L/Departure (Note 3)
Jardine's Lookout
97.9%
1.7%
0.3%
0.0%
07R,07L/Departure (Note 3)
Shau Kei Wan
98.4%
1.3%
0.3%
0.0%
07R,07L/Departure (Note 3)

Note 1 Lmax is the maximum instantaneous noise level of a noise event.
Note 2 Please refer to Appendix A(Open with new window) in the Flight Path Section for the arrival flight path arrangement.
Note 3 Please refer to Appendix B(Open with new window) in the Flight Path Section for the departure flight path arrangement.
Note 4 Statistics are based on data recorded by the Aircraft Noise and Flight Track Monitoring System.
Note 5 The above percentages are with reference to the total movements of aircraft during the period concerned.

5. Since airport opening, several briefings on aircraft noise and flight paths have been given to the concerned District Councils including Kwai Tsing, Sha Tin, Tsuen Wan, Central & Western, Kowloon City, Southern, Yau Tsim Mong, Wanchai, Eastern, North, Islands, Tuen Mun and Sai Kung.

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Aircraft Noise Mitigating Measures

6. The government is conscious of the effect that night-time aircraft operations may have on the local communities and has implemented a number of aircraft noise mitigating measures based on the guidelines of the ICAO to reduce the noise impact caused by these aircraft. Briefly, these are:-

a) since October 1998, subject to acceptable operational and safety consideration, arriving aircraft between midnight and 07:00 am are required to land from the southwest. This measure aims at reducing the number of aircraft overflying populated areas such as Sha Tin, Tsuen Wan, Sham Tseng and Tsing Lung Tau;

b) since October 1998, subject to acceptable operational and safety consideration, aircraft departing to the northeast of the Hong Kong International Airport (HKIA) between midnight and 07:00 am are required to use the southbound route via the West Lamma Channel. This measure aims at reducing the number of aircraft overflying populated areas such as the Kowloon Peninsula and Hong Kong Island. Following further consultation with the district boards and detailed assessment by CAD, the application period was revised from midnight – 07:00 am to 11:00 pm – 07:00 am starting from 7 January 1999.;

c) since August 1999, aircraft departing to the northeast of the HKIA are required to adopt the noise abatement take-off procedures so as to reduce the noise impact on areas located in the vicinity of the HKIA. Under these procedures, aircraft are required to maintain a specified speed and power level during the initial phase of the take-off so as to attain a higher altitude within a short distance. In order to further alleviate the noise impact during take-offs, ICAO revised the noise abatement take-off procedures. Aircraft adopting these revised procedures are required to reduce their power upon reaching an altitude of 800 feet or above to abate aircraft noise. Starting from March 2002, aircraft departing to the northeast of the HKIA are required to adopt the revised noise abatement departure procedures;

d) to reduce aircraft noise at source, effective from late October 1999, airlines are not allowed to schedule aircraft that do not comply with the noise standards stipulated in Chapter 3 of Volume I, Part II of Annex 16 to the Convention on International Civil Aviation (Chapter 3 noise standards) to operate in the HKIA between 11:00 pm and 07:00 am. To be in line with international practice in phasing out noisier aircraft, starting from July 2002, this measure has been extended to cover the whole day;

e) starting from mid-August 2000, all aircraft approaching the HKIA from the northeast between 11:00 pm to 07:00 am are encouraged to adopt the Continuous Descent Approach (CDA), subject to operational considerations. As aircraft on CDA fly higher, noise experienced in areas such as Sai Kung and Ma On Shan will be lowered;

f) the CAD has implemented a new set of flight procedures since 2012 to allow aircraft equipped with satellite-based navigation technology to adhere closely to the nominal centre line of the flight track when departing to the northeast of the HKIA and making south turn to the West Lamma Channel. This keeps the aircraft at a distance away from the areas in the vicinity of the flight paths (e.g. Ma Wan), and reduces the impact of aircraft noise on these areas; and

g) starting from late March 2014, the CAD has no longer allowed airlines to schedule aircraft which are marginally compliant with the Chapter 3 noise standards to land and take off in Hong Kong between 11:00 pm and 07:00 am. With effect from late October 2014, this measure has been extended to cover the whole day, thus further alleviating the aircraft noise impact on the local communities.

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Aircraft Noise Monitoring

7. The CAD monitors the noise caused by aircraft operations through a computerised Aircraft Noise and Flight Track Monitoring System (ANFTMS). The ANFTMS comprises 16 outdoor noise monitoring terminals (NMTs) which are located along or close to the flight paths operating into and out of the HKIA, and a computer to correlate the noise data with the aircraft flight tracks recorded by the CAD's radar system. At present, there are a total of sixteen noise monitoring terminals installed which are located respectively at Sha Lo Wan, Tung Chung, Sunny Bay (formerly known as Yam O), Ma Wan, Tsing Yi (2 terminals), Tam Lam Chung, Tsing Lung Tau, Ting Kau, Tsuen Wan, Kwai Chung, Tai Wai, Mid-Levels, North Point, Jardine's Lookout and Shau Kei Wan.

8. As regards the measures mentioned in paragraph 6(a) and (b) above, Tables 1 and 2 below show the achievement figures. The results indicate that high percentages of achievement have been attained during the periods with the implementation of the measures. These measures could not be applied only on a small number of occasions due to various operational reasons including prevailing wind conditions, maintenance of navigation aids prior to flight calibration, or air traffic conflicts.

Table 1 – Achievement record for aircraft arriving between 00:01 and 07:00 hours to land from the southwest when wind conditions and traffic situation permit.
Year
Total number of aircraft arriving between 00:01 and 07:00 hours
Total number of aircraft landed from the southwest during the same period
Achievement Rate (%)
1998 (Oct-Dec)
1,066
1,037
97.3%
1999
4,720
4,293
91.0%
2000
5,695
5,248
92.2%
2001
5,526
5,201
94.1%
2002
7,065
6,660
94.3%
2003
6,838
6,409
93.7%
2004
8,641
7,958
92.1%
2005
10,865
9,437
86.9%
2006
12,622
11,126
88.1%
2007
14,002
11,950
85.3%
2008
14,869
13,263
89.2%
2009
13,266
12,201
92.0%
2010
17,126
14,704
85.9%
2011
19,713
17,174
87.1%
2012
21,099
18,006
85.3%
2013
24,111
21,434
88.9%
2014
27,655
23,601
85.3%
2015
30,039
23,548
78.4%

Year 2016

Month
Total number of aircraft arriving between 00:01 and 07:00 hours
Total number of aircraft landed from the southwest during the same period
Achievement Rate (%)
January
2,608
2,586
99.2%
February
2,340
2,190
93.6%
March
2,594
2,594
100.0%
April
2,447
1,828
74.7%
May
2,408
1,788
74.3%
June
2,365
1,439
60.8%

Note 1: Statistics are based on data recorded by the Aircraft Noise and Flight Track Monitoring System

Table 2 – Achievement record for aircraft departing on Runway 07 between 23:00 and 07:00 hours (Note 1) to use the southbound route via the West Lamma Channel.
Year
Total number of aircraft departing on Runway 07 between 23:00 and 07:00 hours*
Total number of departing aircraft using the southbound route during the same period
Achievement Rate (%)
1998 (Oct-Dec)
802
794
99.0%
1999
5,913
5,871
99.3%
2000
9,737
9,686
99.5%
2001
10,790
10,634
98.6%
2002
11,416
11,365
99.6%
2003
11,382
11,340
99.6%
2004
14,104
13,989
99.2%
2005
16,115
15941
98.9%
2006
18,533
18,340
99.0%
2007
19,596
19,449
99.2%
2008
21,492
21,239
98.8%
2009
21,162
21,034
99.4%
2010
23,195
22,860
98.6%
2011
25,389
25,170
99.1%
2012
26,705
26,605
99.6%
2013
30,035
29,777
99.1%
2014
28,761
28,385
98.7%
2015
27,221
26,895
98.8%

Year 2016

Month
Total number of aircraft departing on Runway 07 between 23:00 and 07:00 hours*
Total number of departing aircraft using the southbound route during the same period
Achievement Rate (%)
January
2,953
2,879
97.5%
February
2,462
2,458
99.8%
March
3,034
2,997
98.8%
April
2,108
2,094
99.3%
May
2,058
2,002
97.3%
June
1,702
1,664
97.8%

Note 1: Prior to 7 January 1999, the period was 00:01 – 07:00 hours.
Note 2: Statistics are based on data recorded by the Aircraft Noise and Flight Track Monitoring System.

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Aircraft Noise Complaint

9. Complaint Hotline: 2769 6969
Email: aircraftnoise@cad.gov.hk(Open with new window)
Fax: 2795 8469
Aircraft Noise Complaint Office
Civil Aviation Department Headquarters
1 Tung Fai Road, Hong Kong International Airport
Lantau, Hong Kong