American, Delta, and United's average fleet ages are similar, and all of these carriers have a mix of aging and modern aircraft.

Narrator: We went on board Delta's redesigned Boeing 777 with the people whose job it is to make flying suck a little less. Delta announced the redesign of its entire 777 fleet back in 2018.

American Airlines is doing away with long-haul first class on many planes in favor of a larger single cabin with new suites.