Designed in the 1950s as a high-altitude strategic bomber, the XB-70 cruised above 70,000 ft at over Mach 3 (≈3,200+ km/h). At those speeds, aerodynamic heating pushed skin temperatures beyond 300°C in some areas. Aluminum would have softened—so engineers used stainless steel honeycomb sandwich panels and brazed structures to survive sustained thermal loads. The Valkyrie’s most radical feature was its compression lift system. The forward fuselage and large delta wing were shaped to trap and “ride” its own shockwave at supersonic speed. The wingtips could droop up to 65 degrees in flight, increasing directional stability and enhancing lift by managing shock interactions under the wing. Instead of fighting shockwaves, the XB-70 exploited them. Propulsion came from six General Electric YJ93 turbojets, optimized for sustained Mach 3 cruise. Variable-geometry inlets precisely controlled airflow, slowing supersonic air before it reached the compressors. At cruise, the aircraft operated in ...