Cash balances vary by quarter. If you look at American, for example, they were close to 20% mid-year 2019. They were down to about 10% by the end of the year. But that is indicative of an overall problem the airlines were having even before this pandemic that no one was really paying much attention to: operating margins have been steadily declining since 2015, as have cash balances. The airline industry still suffers from many of the same problems that it did pre-bankruptcy era. People are razzle-dazzled by billion dollar quarters because it sounds like a big number, but the reality is that American had a 3.5% net margin and a 6% operating margin last year. United wasn’t much better. Only Southwest really had an enviable business. Delta was doing much better than United and American, but even they were just barely clinging to 10% margin, which isn’t much breathing room in that highly cyclical business.
The airlines were poised for collapse at the first sign of economic trouble. The pandemic and shutdowns were just the trigger this time. Just like 9/11 was the trigger last time.
It’s a crappy business. It needs to be regulated. Until Congress does that, it will suffer a never-ending cycle of (semi)boom and boost. But the executives aren’t bad at what they do. They make the best of the crappy business they’re stuck managing.