Stealth Bomber Redux: Part 1 Beginnings: Jack Northrop and the Flying-Wing – The following is a multi-part series detailing the origins of the B‑21 Raider stealth bomber from the YB-49 and earlier. This is part one. 
In the mid-1970s, Northrop (later to become Northrop Grumman) and Lockheed (later to become Lockheed Martin) squared off against each other for a U.S. government contract to build the world’s first operational all-spectrum stealth aircraft. Both companies went to great lengths to usher in the low-observables technology that held the potential to dramatically transform the nature of air warfare by making planes all but invisible to radar. In the end, the nod went to Lockheed whose design, after refinements, entered the Air Fo …