"The plane is landing" is a common way to describe an airplane that is in the process of descending and preparing to touch down on the runway. "The plane has landed" is used to describe an airplane that has successfully landed and come to a stop on the runway.

In written Engpsh, you might describe the landing of an airplane pke this:

"The plane began its descent, its engines roaring as it prepared to land. As it approached the runway, it slowed and touched down smoothly, rolpng to a stop at the gate."