A320 Fcom 1.22.30 P12 Speed/mach Switching
I confess I don't fully understand when and why the selected speed target switches to mach target (or the opposite in descent).
When speed is managed I understand that, as there is a known speed/mach schedule, the FMGC knows what the crossover altitude is, and changes over exactly at the crossover altitude. Am I correct?
In selected speed, however, the FMGC doesn't know what our plans are for the climb (or descent), so it switches to mach (or speed) at a FL according to the table in this paragraph. Am I correct? For a given climb IAS there is a given mach number and a crossover FL? And for a given descend mach number there is a given IAS and a given crossover FL? If so, I don't know very well how to read that table.
For instance, climbing at 300 kt, What will occur? switch to 0.76 at FL265 always?
And what about descending at 0.76? will the target switch to 280 kt at FL305always?
What about climb speeds lower than 280? Is it that at any speed lower than that the switching will occur always at FL305, whatever the actual mach number?
And what about descending mach numbers lower that 0.76? Is it that at any mach lower than that the switching will occur always at FL 305 no matter what the IAS?
thanks