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
Ka On Building - (Based on the measured helicopter noise results at Ka On Building)
      S76C+    
Event LA LA w/o bk LA with Distance Correction Corrected LA with Screening effect Duration, s
Pass By (approach) 66.5 66.5 66.5 66.5 50
Approach 66.5 66.5 66.5 66.5 27
Hovering 70.9 70.9 70.9 70.9 30
Idling 62.5 62.5 62.5 62.5 675
Hovering 67.3 67.3 67.3 67.3 61
Take off 75.6 75.6 75.6 75.6 12
Pass By (away) 78.6 78.6 78.6 78.6 12
    867
Distance 264.0 (T1)
Corrected Distance 264.0  
Distance Correction 0.0  
     
Corrected Leq(helicopter) for a event = 66.1 (SPL1)  
     
No. of flights    
N = 11 (22 movements)**  
Leq(4-hour) = 64.3        
Note:
** current maximum allowable flight frequency during 1900 to 2300