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Old 28th Aug 2013, 13:36
  #89 (permalink)  
Capn Bloggs
 
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Retired F4, there are other official documents around from EU land that address the MDA + 50 ft technique used during CDFAs; sorry but I can't put my finger on them.

That reference you quoted is the biggest load of nonsense I have read on CDFAs. Pointing the aeroplane toward the ground at 632ft/min (120KIAS) (in it's example) and hoping that 1/ you'll miss the steps and 2/you won't be 4 whites or reds on the PAPI when you pop out of the cloud is guesswork at best. It also doesn't cover how you magically arrange to be at 5.9DME already on descent so you don't have to compensate for the bunt for the final approach.

Unless you have VNAV, the only surefire way of doing CDFAs is to use a profile which should be printed on the chart. The aeroplane will then be assured of missing all the steps and be positioned correctly on the slope, not excessively high or low.
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