As far as I can recall.........
With respect to screen heights and obstacle clearance, when planning departure procedures, they run a slope of 152ft/nm starting from the 35ft screen height upward to at least 1500ft agl. Then they run another slope just 48 feet below this and asess this area for obstacles. If any obstacles penetrate this 48ft clearance area they apply an obstacle clearance departure procedure.
In the case of a reduced screen height of 15ft under wet conditions, obstacle clearance is reduced but still assured.
AL
Last edited by alrb211; 22nd Jun 2007 at 01:09.