From the A320 FCOM:
FLIGHT CONTROL TAKE-OVER
Because of the nature of fly by wire and Sidestick systems, PNF control inputs to correct the PF inputs are not recommended. If take-over becomes necessary during flight, the PNF clearly announces "I HAVE CONTROL" and assumes control of the aircraft. If required, the Sidestick Priority Pushbutton is pressed and held until the transfer of control is clearly established.
We have a FOQA event for dual control inputs and the results are reported in regular FOQA Reports. Sometimes it is a crew (captain) contact to find out why. Sometimes it is line-indoc, sometimes not, but the matter is addressed as it is considered a serious operational matter. It is abundantly clear in the FCOM: dual inputs on an Airbus are a no-no.
PJ2
Last edited by PJ2; 6th Mar 2011 at 20:02.