Assuming "re-entry" means "to decelerate from (near) orbital velocity" and not "to pass from vacuum-to-atmosphere", isn't this a solved problem for fast high-al

Assuming "re-entry" means "to decelerate from (near) orbital velocity" and not "to pass from vacuum-to-atmosphere", isn't this a solved problem for fast high-altitude jets (e.g. SR-71 Blackbird, 3,529.6 km/h). Wait, I see the problem: ((3 529.6 * 1000) / (60 * 60)) / 340.29 = 2.88120263 The fastest jet plane only does 2.88 mach... not 10+ mach.