How Long Do Planes Last In Years?

About 10 years.

They last 30 years or more if they are maintained . They have to be inspected all the time anyway in order to be safe. Parts that are worn are replaced, so an old plane is not really the same plane anymore.

The USAF used B-52 bombers made around 1955 until 1995 or so. . The big reason a plane is retired is that is has become obsolete, not because it won't fly.