Test result shows: this method can improve the accuracy and efficiency of fan trouble diagnosis.

Another model, the "Oorja", developed by BP and the Indian Institute of Science, has an integrated battery-powered fan to direct air to wood pellets in the combustion chamber, improving efficiency.

One way to increase the efficiency of a high-bypass jet engine is to turn the fan into an open rotor, a bit like returning to propellers, but using two rings of stubby counter-rotating blades.