What’s more, at its highest speeds, the engine transitioned from conventional turbojet to mostly ramjet compression by extending/retracting a nose cone within each engine intake. Doing so moved the bow shockwave of the cone so that it reflected inside the engine intake, which had the effect of slowing the Mach 3 air down to subsonic speeds so it could be used for engine combustion. But even still, energies were so high that almost all the thrust came from afterburning - the engine combustion stages were basically just spinning as air went through them.
The whole plane is an engineering tour-de-force, especially considering it was designed with slide rules
The fuel doesn't ignite at "low" temperatures, one reason is because the whole airplane leaks fuel until it's at an high enough speed. At that point, maybe because of the surface temperature, or the forces it tackles at Mach 3+, the whole thing becomes airtight.
Yup, at Mach 3+ the fuselage expands so significantly that gaps need to exist when it’s stationary, otherwise it’d buckle. So the gaps mean it leaks fuel when stationary.
