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Old 26th Oct 2020, 12:27
  #18 (permalink)  
chevvron
 
Join Date: Nov 2005
Location: Wildest Surrey
Age: 75
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Originally Posted by ShyTorque
I always understood the steeper glidepath angle was to avoid "Cody's Tree".
Not since it was 'stolen' by DRA/DERA/Qinetiq and moved to Cody Site about a mile to the northwest.
3.5 deg GPs were adopted due to a design system called 'APATC-1' which was mandated for MOD airfields back in the '80s.
This involved a different way of calculating approach minima compared to the ICAO method used for civil airfelds, the 'dominant obsatcle' on runway 24 being --- the control tower!!
Once that was demolished in early 2003, we could have reduced to a 3 deg GP under both APATC-1 and ICAO methods of iap design.
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