China is unleashing stealth drones and pilotless aircraft fitted with AK-47 rifles onto world markets, racing to catch up to US technology and adding to a fleet that has already seen combat action in the Middle East. The US has plenty of lethal drones, but it has had restrictions on exporting them out of concern that the technology could be copied or used against its own troops. The US rules gave Beijing the opportunity to fill the void and sell its drones to other countries, but China’s “competitive” prices also helped, said Mr James Char, an expert on the Chinese military at Singapore’s NTU.