Delta Air Lines is America's oldest operating airline, the second largest airline in the world, and the world's most valuable ...

On the other hand, Delta Air Lines' fleet age is 15.3 years. This is much older, especially considering that it's a mainliner. And while its jets aren't as thrifty as Spirit's, it allows the ...

Delta operates a mainline fleet of more than 700 aircraft. As a founding member of the SkyTeam global alliance, Delta participates in the trans-Atlantic joint venture with Air France-KLM and Alitalia.