August 24, 2010
. . . but there are tantalizing clues, such as images of high-altitude doughnut-shaped sonic boom contrails . . . and the sonic evidence perceived by the presenter of this clip.
The presenter heard a series of sonic booms while in either California or Nevada — something that could be heard, felt but not seen.
Alarmingly there’s no evidence of government spending on this plane.
Its doughnut-shaped exhaust pattern indicates it uses a pulse detonation wave engine. It’s enough power to drive an airplane to six times the speed of sound.