In the first episode of season 3, “Through the Time Barrier” (23 Mar 1955), Professor Twiddle’s time machine takes the staff of the Daily Planet back to prehistoric times. I don’t know whether there was any other time travel.
Faster than a speeding bullet! More powerful than a locomotive! Able to leap tall buildings in a single bound! Look—up in the sky! It’s a bird! It’s a plane! It’s Superman!

Yes, it’s Superman, strange visitor from another planet who came to Earth with powers and abilities far beyond those of mortal men. Superman, who can change the course of mighty rivers, bend steel in his bare hands, and who—disguised as Clark Kent, mild-mannored reporter for a great metropolitan newspaper—fights a never-ending battle for truth, justice, and the American way!

Variants

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  1. Adventures of Superman by Whitney Ellsworth and Robert J. Maxwell (23 April 1955).
  2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . written by Whitney Ellsworth