A Chinese aerospace firm’s claim that it is developing a “flying train” capable of travelling at up to 4,000 km/h has met with scepticism and wry humour from transport experts and members of the public in China. China Aerospace Science and Industry Corporation announced plans on Wednesday to research a futuristic train network that would first run at 1,000km per hour between cities, eventually developing to reach top speeds of 4,000km/h. That target is well over 10 times faster than the maximum speed of existing bullet trains. The idea was unveiled by Liu Shiquan, the corporation’s deputy chief executive, at...