If it's related to GS capture, MCP altitude setting, etc, how does it even change 100' before the CVR hears 'click' and 'click'(sounds of A/P and A/T disconnecting)?
One of the worst things to watch is to see the a/c displacing from the intending flight path, especially fairly abruptly due to false GS capture, TOGA engagement, etc, and see the flying pilot try to figure out what mode the FMC/AP is in. Who cares? Turn it off, hand fly it along the desired flight path, and reestablish the appropriate level of automation.
'Click' 'click' is the fastest way to reestablish direct control of the airplane. Is it needed for most situations? No. Knowing how to work the FMC/AP is important. But equally important is understanding when manual control is required. Disengaging the AP when simple FMC/AP entries would fix the problem is not the goal either. Know the level of automation appropriate (hand flown, AP-V/S ALT HOLD, speed intervention, FMC-LNAV, VNAV, speed intervention, etc) and achieve the mode needed for the situation. IF the a/c isn't performing as desired/required YOU fix the problem.
Using the wrong level of automation seperates the men from the boys. Inappropriate mode use can be painful to watch.
Last edited by misd-agin; 6th Apr 2013 at 13:37.
Reason: replaced . with a ?