China is almost doubling the number of civilian aeroplanes that are allowed to fly in its airspace at any one time as part of a regulatory overhaul designed to help reduce flight delays caused by the military’s tight control over the country’s airspace.

Under new rules that come into effect Thursday, the aviation regulator will halve the height of each flight layer between 8,900m and 12,500m, increasing the number of layers from 7 to 13 and nearly doubling the number of planes that can fly through the same area simultaneously.