Overheard a pilot say his autopilot was 'twitchy' on final approach

I used to think a 'twitchy' feel was just a pilot preference thing, not a real fault. He described it as a slight, rhythmic pitch hunt, which made me check the servo clutch tension on that A320. It was actually a quarter-turn out of spec. How do you guys usually start diagnosing vague 'feel' complaints from the flight deck?

3 comments

3 Comments

charles4421mo ago

A buddy found a loose trim cable after a similar complaint.

-1

hannahm391mo ago

Yeah, @charles442, that's a solid find. Seen a few where the cable was tight but the actual trim motor was just shot.

charles4421mo ago

The 2018 models had a known issue with the trim motor bracket. I've replaced three of those brackets myself for a loose feel. The cable usually checks out fine on those.