Is Heinlein's 1941 story Orphan's of the Sky the first instance of a generation ship where the current inhabitants have almost completely forgotten how to run the ship, and are mostly unaware of anything outside of this ship?

If not, where does this idea come from?

Note: Asimov's short story Reason was published one month prior and has similar themes, but instead of a generation ship used robots who had never experienced any other environment than the small space station they were activated on.