[mabarker1]

The Early Bird:

https://www.nationalmuseum.af.mil/Visit/Museum-Exhibits/Fact-Sheets/Display/Article/858861/northrop-yb-49/

https://www.warhistoryonline.com/aircraft/northrop-yb-49.html

[Svartalfiar]

The Early Bird: northrop-yb-49

You're not even close to going back far enough:

https://www.bbc.com/future/article/20160201-the-wwii-flying-wing-decades-ahead-of-its-time