The A321 exhibits a strange short-period vertical oscillation (i.e. the aircraft rocks back and forth pretty rapidly) whenever I’m at flaps full, gear down, and attempting to maintain level flight (e.g. fully configured for landing but not yet fully established on the glideslope). This instability persists with autopilot both ON and OFF, at both maximum allowed placard speed and VREF, and regardless of wind/weather conditions. The tendency diminishes somewhat when descending toward the runway, but it seems to return at short final, making touchdown…let’s call it “more exciting” than I have experienced in other comparable aircraft in the IF fleet.
At first I thought it was pilot error (or something that’s a unique quirk of the A321 that the designers wished to ), but I’m not seeing these flight dynamic issues in the A320, A319, or A318. Is anyone else experiencing this?
Apologies if this is a duplicate… I searched the forum for A321 phugoid, oscillation, flight dynamic, etc and didn’t find anything. Also idk if this is the right place to post this; mods please move this as appropriate.