By Dan Weil American, Delta and Alaska Air posted record sales in the first quarter, and United expects to do so in the second quarter. This is a great time to be an airline — a marked contrast to the doom-and-gloom environment of the Covid pandemic’s early days. Fare prices are blasting higher, and consumers are happy to pay them after being stuck at home for much of the pandemic. American Airlines (AAL) – Get American Airlines Group, Inc. Report, Delta Air Lines (DAL) – Get Delta Air Lines, Inc. Report and Alaska Airlines (ALK) – Get Alaska Air Group, Inc. Report posted record revenue in the…