Should a dual FMGC failure occur, the AP/FD and A/THR will disconnect. The crew
will try to recover both AP and A/THR by selecting them back ON (The AP and
A/THR can be recovered if the FG parts of the FMGS are still available).
If both AP and A/THR cannot be recovered, the thrust levers will be moved to
recover manual thrust. The pilot will switch off the FDs and select TRK / FPA to
allow the blue track index and the bird to be displayed. The RMPs will be used to
tune the NAVAIDs