China’s plasma drive can nearly double high-altitude drone efficiency, study says
Tests by Chinese scientists show that plasma excitation tech can boost performance of high-altitude drones, allowing them to fly longer

Based in Mianyang in Sichuan province, CARDC operates some of the world’s largest and most advanced wind tunnels – a facility crucial for simulating flight conditions. The team’s April paper was published in the Chinese Journal of Theoretical and Applied Mechanics, China’s top aerodynamics journal.
While cutting-edge military drones like the US RQ-4 Global Hawk and China’s CH-9 can already loiter at altitudes above 10,000 metres (32,800 feet) for 40 hours, aerodynamics experts believe these machines can fly even longer.

Slower speeds can lead to longer endurance, but thinning air at extreme altitudes severely degrades efficiency.