In the future, it´s going to get more complicated:
The A318 - she looks clearly more stubby than the A319, also due to a higher tail. But the main distinguishing feature, the exit configuration, is the same as on the A319.
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Photo © Ben Pritchard
The A319 - apparently Airbus is looking into adding another pair of overwing exits to suit the needs of holiday/low cost airlines, who want to increase passsenger capacity - should this option materialise, it will be difficult to tell these A319s from A320-200s with the same exit layout.
The A320 - notice something missing in the photos below? Yup, that´s the -100 series which has no winglets. Given the fact that only 20 were built and the remaining 18 are flying for AF (13) and BA (5), you´ll not see them in America for the moment. But I wouldn´t be too surprised if they were to show up on the used planes market in the not too distant future - they´re 14 years old, after all - and then they might make it into other than European skies.
The A321 - there are the -100 and -200 series - no external difference, but the -200 is a kind of "ER" version.
Hope I didn´t confuse you too much, Patrick,
Daniel
