Scheduled drone performances at tourist attractions and events across China have been grounded as the country steps up scrutiny of low-altitude aviation, although in many cases no clear reason was given for the cancellation. Tourist attractions and event organisers in 11 provinces and regions – including Inner Mongolia, Gansu, Shandong, Guangdong and Hainan – took the unusual step last week of announcing that drone shows scheduled from Friday onwards were cancelled. By Monday, none had announced...