Never been a great fan of 'Arm' for landing, as I have heard of and seen examples of the so-called 'alpha-floor' kicking-in during a flare at a higher than normal retard height (>25ft, from memory?), when it detects an ensuing 'stall', and application of reduced g/a power at that moment is disconcerting! It can also be a nuisance at some weights/flap settings since 1.3xVstall can be less than Vref+5 (not that anyone seems to fly that
) - I have the 'calcs' somewhere.
Reasons given to me by a very boring IRE for using it were:-
Stall protection (on short finals!!
)
Autothrottle g/a application (useful on s/eng g/a), thereby
Allowing use of reduced g/a power (one push of g/a button) rather than HAVING (his words!) to use full g/a to satisfy the 'rules'.
We'll have to wait for the 'revision' and see what happens?