Methods and apparatus for cooling a surface on a flight vehicle and generating power include advancing the vehicle at a speed of at least Mach 3 to aerodynamically heat the surface. A first working fluid circulates through a first fluid loop that heats the first working fluid through a first heat intake thermally coupled to the surface and expands the first working fluid in a first thermal engine to generate a first work output. A second fluid loop has a second working fluid that receives heat from the first working fluid and a second thermal engine to generate a second work output. The first and second work outputs are operably coupled to first and second generators, respectively, to power primary or auxiliary systems on the flight vehicle.