High Supersonic Aircraft

Typical speeds for high supersonic aircraft are greater than 1500 mph but less than 2500 mph. The Mach number M is then greater than three, but less than five, 3 < M < 5. In addition to the high temperatures, they’d encounter compressibility effects and the local air density varies because of shock waves, and expansions.

The only aircraft to cruise in this regime were the XB-70 and the SR-71/YF-12.

Reference: NASA