The North American XB-70 Valkyrie embodied a once-dominant creed: outrun defenses at Mach 3 and 70,000 feet. -The prototype ...
A Boeing F-15 is still quite fast, but not nearly Mach 3, the company’s program manager said on Feb. 23, correcting a previous statement. “Mach 2.497 is what we can get out of the Eagle jet and that’s ...