| Appendix 3.7b Calculation of Helicopter Noise
at the Proposed Helipad, Leq (4 hours) During 1900 - 2300 hrs |
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| Mode
1 - Approach from East and Take off to West |
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| Ka
On Building - (Based on the measured helicopter noise results at Ka On
Building) |
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| |
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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) |
66.5 |
66.5 |
64.6 |
64.6 |
50 |
|
| Approach |
66.5 |
66.5 |
64.6 |
64.6 |
27 |
|
| Hovering* |
70.9 |
70.9 |
69.0 |
64.0 |
30 |
|
| Idling* |
62.5 |
62.5 |
60.6 |
55.6 |
675 |
|
| Hovering* |
67.3 |
67.3 |
65.4 |
60.4 |
61 |
|
| Take off |
75.6 |
75.6 |
73.7 |
73.7 |
12 |
|
| Pass By (away) |
78.6 |
78.6 |
76.7 |
76.7 |
12 |
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| |
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|
867 |
|
| 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 = |
62.3 |
|
(SPL1) |
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| No.
of flights |
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| N = |
11 |
|
(22 movements) |
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| Leq(4-hour)
= |
60.5 |
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| Note: |
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| *
5dB(A) deduction for screening effect from Shun Tak Building during idling /
hovering(as Shun Tak Building has partial screening for the helicopter during
measurement in some events) |
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