Flying blind at Mach 1: how China is bringing world’s first supersonic rail to life

A rail system that accelerates heavy objects faster than the speed of sound using pure electromagnetic force has been operating in the eastern Chinese city of Jinan for more than two years. But one of the biggest mysteries remains: how does it stay in control? The sonic boom the system generates at ground level could blind or wreck traditional sensors, while the slightest miscalculation due to missing data could mean disaster at supersonic speeds. The system, known as the electromagnetic sledge,...