| Appendix 3.7b Calculation of Helicopter Noise
at the Proposed Helipad, Leq (4 hours) During 1900 - 2300 hrs |
| Mode
2 - Approach from West and Take off to East |
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| Ka
On Building - (Based on the measured helicopter noise results at Ka On
Building) |
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|
S76C+ |
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| Event |
LA |
LA w/o
bk |
LA with Distance Correction |
Corrected LA
with Screening effect |
Duration, s |
|
| Pass By (approach) |
72.9 |
72.9 |
71.0 |
71.0 |
22 |
|
| Approach |
79.1 |
79.1 |
77.2 |
77.2 |
32 |
|
| Hovering* |
81.1 |
81.1 |
79.2 |
74.2 |
30 |
|
| Idling* |
63.5 |
63.5 |
61.6 |
56.6 |
668 |
|
| Hovering* |
77 |
77.0 |
75.1 |
70.1 |
51 |
|
| Take off |
73.9 |
73.9 |
72.0 |
72.0 |
13 |
|
| Pass By (away) |
66 |
66.0 |
64.1 |
64.1 |
30 |
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| |
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|
846 |
|
| Background Level |
0.0 |
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| Distance |
264.0 |
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|
(T1) |
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| Corrected Distance |
328.0 |
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| Distance Correction |
-1.9 |
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| Corrected Leq(helicopter)
for a event = |
66.6 |
|
(SPL1) |
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| No.
of flights |
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| N = |
11 |
|
(22 movements) |
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| Leq(4-hour)
= |
64.7 |
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| Note: |
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| *
5dB(A) deduction for screening effect from Shun Tak Building during idling /
hovering |
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