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
The Bauhinia - (Based on the measured helicopter noise results at Harbour Commercial Building)
      S76C+    
Event LA LA w/o bk LA with Distance Correction Corrected LA with Screening effect Duration, s
Pass By (approach) 66.8 66.8 66.4 66.4 50
Approach 74.9 74.9 74.5 74.5 27
Hovering 79.4 79.4 79.0 79.0 30
Idling 61.2 61.2 60.8 60.8 675
Hovering 75.9 75.9 75.5 75.5 61
Take off 78.4 78.4 78.0 78.0 12
Pass By (away) 74.1 74.1 73.7 73.7 12
  867
Distance 213.0 (T1)
Corrected Distance 222.0  
Distance Correction -0.4  
   
Corrected Leq(helicopter) for a event = 69.3 (SPL1)  
   
No. of flights  
N = 8 (16 movements)**  
Leq(4-hour) = 66.2        
Note:
** existing flight frequency during 1900 to 2300