It was “a year of going through hell” for United Airlines. Delta Air Lines had “the toughest year” in its history. And for American Airlines it was “the most challenging year.” That’s how the executives who run those companies described 2020 in recent weeks.The airline industry is eager to move on, but it hasn’t figured out how.Air travel has recovered somewhat in recent months, but it remains deeply depressed compared with 2019, and no one knows when business will return to more normal levels. Two essential moneymakers for airlines — corporate and international travel — are likely to stay sidelined …
