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Old 25th Feb 2010, 20:46
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Kirks gusset
 
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I'm even more curious now, from the dialogue it would appear that there is a suggestion from some that you draw a CDFA from 3000 platform turn to the 50 ft TCH? What happened to the concept of MDA, 560 ft in this case, so surely, the NPA " Glide" must be constructed to cross the MDA point at the correct DME and not at the TCH.

I am aware that no one flys a level flight segment.

By my simple maths, 3000 -560= 2440 at 3 degrees CDFA , just over 8 miles, this will put you at MDA about 1 mile from the VOR inbound, which is far too far out, hence the profile as drawn.

Surely a CDFA would need the first descent from 3000 to 1900 at about 1.5 degrees ( 1100 ft loss over 7 miles) the second descent is then at 3.05 degrees, 1900 to 560 ft

In operational terms, that just means increasing the rate from 1.5 to 3 degrees at a point 0.3 DME from the VOR inbound ( 5.3 DME)

Last edited by Kirks gusset; 25th Feb 2010 at 21:06.
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