Appendix 3.7a Calculation of Helicopter Noise
at the Existing Helipad, Leq (4 hours) During 1900 - 2300 hrs |
Mode
1 - Approach from East and Take off to West |
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The
Bauhinia - (Based on the measured helicopter noise results at Harbour
Commercial 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 |
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Pass By (approach) |
66.8 |
66.8 |
66.4 |
66.4 |
50 |
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Approach |
74.9 |
74.9 |
74.5 |
74.5 |
27 |
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Hovering |
79.4 |
79.4 |
79.0 |
79.0 |
30 |
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Idling |
61.2 |
61.2 |
60.8 |
60.8 |
675 |
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Hovering |
75.9 |
75.9 |
75.5 |
75.5 |
61 |
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Take off |
78.4 |
78.4 |
78.0 |
78.0 |
12 |
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Pass By (away) |
74.1 |
74.1 |
73.7 |
73.7 |
12 |
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867 |
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Background Level |
0.0 |
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Distance |
213.0 |
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(T1) |
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Corrected Distance |
222.0 |
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Distance Correction |
-0.4 |
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Corrected Leq(helicopter)
for a event = |
69.3 |
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(SPL1) |
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No.
of flights |
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N = |
11 |
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(22 movements)** |
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Leq(4-hour)
= |
67.5 |
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Note: |
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**
current maximum allowable flight frequency during 1900 to 2300 |
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