There are many different ways to measure the size and influence of an airline. For starters, one might want to look at the number of passengers carried by an airline. Alternatively, they might also want to look at the number of daily flights an airline operates, which would also provide a decent metric of which carrier might just be the world’s largest. If an analyst were to use either of these metrics to attempt to identify what airline is the world’s largest, they would land on American Airlines.