You can see it used here: https://youtube.com/shorts/nBmPXrBpp3Y
You hear the normal 50.. 30.. etc. callouts and then when the captain goes full thrust you hear "priority left" which is the override button being pressed to pitch for go-around.
That's much nicer than what we have teaching with traditional controls. Because at that point overpowering a startled pilot is a bit hard.
FDR visualization: https://www.youtube.com/watch?v=0a06A78iXnQ
Interesting that the FO flying from the left seat did not recognise that callout as a big thing to react to.
(Unless you manage to hit the priority button for 40 seconds - but I assume that's for locking out a broken stick that's doing inputs at rest)
It's a bit different for a training captain like in the video. They know these are the first officer's first landings on the real aircraft, so when things go wrong they take over.
Section 6
> When a dual input situation is detected, the two green priority lights located on the cockpit front panel flash simultaneously.
> After the visual indication has been triggered, a synthetic voice “DUAL INPUT” comes up every 5 sec, as long as the dual input condition persists.
According to Wikipedia, this warning system worked as intended:
> Confused, Bonin exclaimed, "I don't have control of the airplane any more now", and two seconds later, "I don't have control of the airplane at all!"[42] Robert responded to this by saying, "controls to the left", and took over control of the aircraft.[83][44]
> He pushed his side-stick forward to lower the nose and recover from the stall; however, Bonin was still pulling his side-stick back. The inputs cancelled each other out and triggered an audible "dual input" warning.
> ...
> Bonin heard this and replied, "But I've been at maximum nose-up for a while!" When Captain Dubois heard this, he realized Bonin was causing the stall, and shouted, "No no no, don't climb! No No No!"[85][44]
> When Robert heard this, he told Bonin to give him control of the airplane.[2] In response to this, Bonin temporarily gave the controls to Robert.[44][85][2] Robert pushed his side-stick forward to try to regain lift for the airplane to exit the stall. However, the aircraft was too low to recover from the stall. Shortly thereafter, the ground proximity warning system sounded an alarm, warning the crew about the aircraft's imminent crash with the ocean.
This is a very bad design - at a bare minimum an incredibly loud and annoying alarm should go off if the pilots are fighting controls, because neither knows what the plane is receiving as an input.