An advanced Chinese weapon has taken down an unmanned aircraft with a powerful electromagnetic pulse in the first known field test of the Beijing technology. The electromagnetic pulse (EMP) weapon was fired at the aircraft while it was flying 1,500 metres (4,920ft) above sea level before crashing down. The experiment, conducted by Chinese defence contractor China Electronics Technology Group (CETC), is thought to be China's first openly reported field test of an electromagnetic pulse weapon in the race to catch up with the US. The EMP weapon used in the test operated within a narrow band, meaning the microwave beam…