The latest safety first seems rather apt given this thread.
https://safetyfirst.airbus.com
Only one flight crew flies at a time
Case study 2 shows that the PM may intend to take control in such dynamic situations. As per the FCTM chapter about the use of sidestick: only one flight crew flies at a time. If the PM intends to apply inputs using the sidestick, they must do the following actions:
- Clearly announce “I have control"
- Press and maintain the sidestick priority pushbutton in order to get full control of the Fly-By-Wire system.
The flight crew should keep in mind that sidestick inputs are algebraically added and the “
DUAL INPUT” alert triggers if the priority pushbutton is not pressed and maintained.
In case study 2, the dual input of the PM on the Captain’s sidestick did not prevent the tailstrike. In other reported cases, the dual input from the PM in the same direction as the PF increased the inputs up to an equivalent of full nose-up, and the resulting increased rate of rotation contributed to the tailstrike.
The latter part seems to be particularly relevant, and explains Airbus’s logic on this matter.