Appendix 3.7a Calculation of Helicopter Noise
at the Existing 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 |
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Pass By (approach) |
72.9 |
72.9 |
72.9 |
72.9 |
22 |
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Approach |
79.1 |
79.1 |
79.1 |
79.1 |
32 |
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Hovering |
81.1 |
81.1 |
81.1 |
81.1 |
30 |
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Idling |
63.5 |
63.5 |
63.5 |
63.5 |
668 |
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Hovering |
77 |
77.0 |
77.0 |
77.0 |
51 |
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Take off |
73.9 |
73.9 |
73.9 |
73.9 |
13 |
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Pass By (away) |
66 |
66.0 |
66.0 |
66.0 |
30 |
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846 |
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Background Level |
0.0 |
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Distance |
264.0 |
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(T1) |
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Corrected Distance |
264.0 |
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Distance Correction |
0.0 |
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Corrected Leq(helicopter)
for a event = |
71.3 |
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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)
= |
69.4 |
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Note: |
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**
current maximum allowable flight frequency during 1900 to 2300 |
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