Originally Posted by
maggot
Shouldn't the AP be slaved to the onside mode C?
Unnecessary overcomplication switching APs, KISSFFS
On the A320 we can select between 1 and 2 and I have always assumed it is selecting between FD1 and FD2 (aka onside AP) although I've never bothered looking into the FCOM as to what that selection does, my knowledge is limited to our SOP which requires the sector PF to select the TCAS onto their side during cockpit prep.