Originally Posted by A33Zab
The 'zipper' means it is - not active - (AP was in ALT HLD mode not in V/S mode)
As you mention, the selected MACH trace shows also a similar 'zipper'.
But my question has been here all along :
WHERE is the
AP/FD vertical engagement mode trace ???
That trace would tell if the 'zipper' is irrelevant.
In the meantime that trace is central to figure what were commanding the FDs when displayed.
Why such trace is missing ?