How old do you think this Delta Air Lines plane is?

If you follow airlines closely, you probably know Delta Air Lines had a media day last week in Atlanta. I attended, and it was a full dog-and-pony show, filled with executive interviews and tours of airplanes. Lots and lots of airplanes. 

I don't fly Delta a lot, so I was most struck by one of the airline's Boeing 757s. Delta is updating many of its older aircraft, including many 757s, and they look like brand new airplanes. This is an 18-year-old plane. But you can't tell, right?

You can see that the 757 with the new interior is nearly identical to Delta's first Airbus A321, pictured below. When I toured this plane, it had yet to fly paying passengers. But it was scheduled to enter revenue service this week.

Once you go up to the cockpit, you can easily see the difference, though. Here's the Boeing 757.

And here's the A321. 

Want to know more about what was discussed at Delta Media Day? Try these stories from other journalists who were there. 

Delta's new CEO: ‘This airline has never performed better’ Ben Mutzabaugh/USA Today

New Delta Air Lines CEO Announces International Premium Economy Product Jason Rabinowitz/Forbes

New Delta CEO takes controls of airline Kelly Yamanouchi/Atlanta Journal-Constitution

Delta Chief Had Long Climb to Top Susan Carey/Wall Street Journal

Ed Bastian Talks About Delta’s Past, Present, and Future Jack Harty/Airways News

New Delta CEO Weighs Cutting Overseas Service as Fuel Costs Rise Michael Sasso/Bloomberg