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Old 18th Apr 2005, 03:55
  #11 (permalink)  
411A
 
Join Date: Mar 2000
Location: Arizona USA
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Tain't always so....

<<A stabilised approach is supposed to be just that. Not bleeding speed in the last 500 feet. Not selecting flap late. Not having to use large thrust/power changes.>>

Doesn't always work out that way, Menen, at least on some types.
Lets consider the Lockheed TriStar as an example.
All coupled up in the approach/land mode, with auto thrust engaged.
I you watch carefully of how the autothrust does it, you might find the following, during gusty wind conditions...

1000 agl (with landing flap selected)....Vref +35
500 agl......Vref +30
200 agl.....Vref + 25
Crossing the threshold....Vref +20.
Touchdown....Vref+15

The Lockheed design engineers went to a rather big effort to design the system for the very best possible results.

Who are you to say that this idea is not correct?
And further, if the pilot hand flies the approach using the very same technique, why should it be 'dangerous' or unacceptable?

To adhere to Vref+20 rigidly at 1000 agl (or even 500 agl) when the aircraft autothrust does it quite differently, in very gusty wind conditions, is very foolish, in my opinion.
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