And A319 is normally operating to airport up to 9200 feet maximum.To operate higher do they have more powerful engines?
A319 in particular is favored for high-aiport operations. Probably because they
do have the same wing as an A320, and
may have equal engines, but have lower operating weights. Does require special certification of craft and crews.
Airbus offers a high-altitude package (cockpit switch enabled) which changes things like the "low cabin altitude" pressurization warning altitude and dropping of cabin pax masks, which normally alerts at 10000 feet. And training in the other issues involved
Another issue is higher TAS on landings and takeoffs - you get closer to tire speed limits. And non-aviation issues (altitude sickness, either among crew or pax)
http://www.caac.gov.cn/ZTZL/RDZT/XJS...3567294102.pdf
The A319 excels in operations from high-altitude airports