FAMILY DIFFERENCES THAT AFFECT THE FLIGHT
A lightly loaded A319 and a longer A321 present different acceleration, ground-geometry and landing considerations. The A321's fuselage deserves particular attention during rotation and flare. When changing model, retain a familiar route if useful, but prepare fresh loading and performance data and review the handling and clearance implications of that airframe. [52, introductory aircraft comparison] [21, PDF pp. 118–121,]
Wingtip fences and Sharklets distinguish visible options, but a Sharklet aircraft can still be a ceo with CFM56 or IAE V2500 engines. Fenix also describes A319 cabin-density and overwing-exit choices, an optional A321 two-class cabin, and an A321 Noise Reduction Package with modified exhaust. Check the actual configuration; the airline name on the fuselage does not establish it. [52, What's Included?] [51, paragraphs on wingtip and cockpit-equipment changes]
An ACT-equipped A321 adds fuel-transfer equipment and occupies cargo space. Review the installed Additional Center Tank configuration with the fuel page and loading setup. The A320 preparation is a useful starting point for cockpit familiarity, but the A321 fuel system requires its own understanding and normal configuration. [52, What's Included?] [51, paragraphs describing ACT installation and aft-cargo location]
Original Fenix FUEL displays: A319/A320 left, A321 right. Inner/outer-wing and transfer arrangements differ; displayed quantities belong to the source examples. [58, Illustrations in the family-differences article]
Original Fenix pack controls: A319/A320 PACK FLOW selector at left; A321 ECON FLOW pushbutton at right. [58, Illustrations in the family-differences article]
Fenix illustration of tail-strike pitch-limit indications. The source article states that the indicator is absent on A319 and differently positioned on A321. LAND is displayed in these source examples; the marks are not flare-attitude targets. [58, Illustrations in the family-differences article]