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fiftypercentn1
25th Jan 2011, 07:04
Hi all, I' d like to crosscheck with you what is the minimum obstacle separation provided, flying level at MDA within the 4.2 NM protected area in a Circling Approach.
thanks

DJ77
25th Jan 2011, 08:12
Plenty. You have a large 500 ft margin, I think.

NorthSouth
25th Jan 2011, 09:40
Category A & B min obstacle clearance 295 ft
Category C & D min obstacle clearance 394 ft

(from PANS-OPS Vol.2)

NS

Tee Emm
25th Jan 2011, 10:13
Plenty. You have a large 500 ft margin, I think

Regardless of the published safety margin above terrain, just remember that at night where you may not be able to accurately see the terrain below you, it would be most unwise to deliberately descent below the MDA until you are established on final approach within the 15 degree approach splay. The reason for this is the critical obstruction that determines the MDA is not necessarily displayed on the instrument approach chart. It could be anywhere- even on early base leg.

hawk37
25th Jan 2011, 10:51
within the 15 degree approach splay

Does this protect you?

Hawk

reynoldsno1
25th Jan 2011, 21:01
The Annex 14 approach splay is 15%, not 15 deg. 15% = 8.3deg