Pinteam: structured reply to your reaction with some answers for the original dilemma later.
For now, consider
F1 at 12 NM
F2 at 8 NM
L/G DN at 4.3 NM
F4 at 3,5 NM
No ABRK, IDLE rev.
Does the SOP profile at your company with FCTM save more fuel? Is it more easy on the brakes?
For airlines whose homebase is 2400 m, is it a smart choice to have pilots fiddle with the flap selection all the time or just unnecessary workload?
I am not calling right or wrong, just pointing out that people no less smart than the two of us combined may have valid reasons to achieve the same or even better results via different paths. And we should not be surprised when that is the case.
Having their application of rules and logic explained in depth often leads to an important discovery about how thorough and truthful I was when doing own homework.
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This will be the core of introducing the answer for C<D you had:
A321 CEO is designed and certified with speeds for a category C aeroplane.
A321 NEO is designed and certified to fly slower or not faster (with the higher weight), so that it can remain C too.
Having 321 CEO as D is an unfortunate result of overthinkig some details, on NAA level admittedly some times.
Flying 321 NEO faster by pilot's choice so much that you push out of the C speed ranges for which it was carefully built
- is a false argument for "should be D"
- might be considered suboptimal decision (underpinning the fact it is impossible to design, certify and categorise within some limits and guarantee someone will not wilfully operate outside of them).
My observation is you need to first ask: What happened that CEO turned out as D for some?
Last edited by FlightDetent; 13th Apr 2021 at 06:43.