Two explanations have competed for the YB-49’s death ever since. The technical case is straightforward: the aircraft was directionally unstable, a poor bombing platform in an age with no computers to steady it, and it had suffered two catastrophic losses. The Convair B-36 — conventional, proven and already in production — simply made more sense as a strategic bomber.

De political case comes largely from Jack Northrop himself, who claimed decades later that Air Force Secretary Stuart Symington had pressured him to merge his company with Convair, and that when he refused the flying-wing contracts were cancelled and the airframes ordered destroyed. Symington did later become an executive at Convair’s parent company, which kept the story alive. Most historians treat the allegation as unproven — a genuine grievance layered over an aircraft that also had real, serious shortcomings. We flag it here as contested rather than settled.

The jet YB-49 exists because its piston predecessor, the XB-35, never worked properly. To turn the huge wing into a bomber, Northrop drove it with four buried Pratt & Whitney engines spinning contra-rotating pusher propellers through long drive shafts and complex gearboxes. Those gearboxes, propeller governors and shafts produced chronic vibration and repeated failures; switching to single-rotation propellers only traded one set of problems for another. The aircraft spent far more time grounded than flying, and by the time the bugs were understood the jet engine had made the whole propeller arrangement obsolete — so two airframes were converted to turbojets as the YB-49.

On 5 June 1948 the second YB-49 broke up in flight near Muroc Dry Lake, killing its entire five-man crew. Among them was Captain Glen W. Edwards, a decorated wartime bomber pilot and test pilot who had privately noted the wing could be “quite uncontrollable at times.” Investigators could assign no single cause but concluded the airframe had suffered a major structural failure. In December 1949 Muroc Air Force Base — today the U.S. military’s premier flight-test centre — was renamed Edwards Air Force Base in his honour. It is the flying wing’s most enduring, if sombre, memorial.

The YB-49 was never a production aircraft, so it has no flyaway unit price in any meaningful sense. It was an experimental prototype programme — two airframes converted from earlier YB-35s, flown only for test and evaluation before cancellation. Its true cost was absorbed into a research effort that produced no operational aircraft, and no credible cost-per-flight-hour figure exists for the type. Any dollar amount attached to a “YB-49” today is at best an allocation of programme spending, not a sourced unit price. The real bill was paid decades later, and far more effectively, in the B-2 programme it foreshadowed.