Watch these great-sounding F-15C Eagle jets blast through the Mach Loop on low-level flybys. The sound is absolutely brutal as the Eagles rip past the hills and the noise echoes through the valleys.

Machynlleth Loop, more popularly, and relevantly for that matter, known as "Mach Loop," is a series of grass covered valleys in central Wales that is known the world over by photographers and aviation ...

Flying low through the Mach Loop leaves no margin for illusion. As RAF Tornado jets entered the valley, speed and mass compressed into a narrow corridor of rock. The aircraft passed first. The sound ...