I don't think AUS
gets any Airbus aircraft anymore. F9
used to fly 319s, but they've switched to CRJs. UA
used to send 319s as well, but they've switched to CRJs and 737s. AC
used to serve AUS
with 319s and 320s, but they've left. US was planning on serving AUS
with 319s before 9/11, but it never materialized.
FedEx also used to send A300s, but no longer ...