The Korea Advanced Institute of Science and Technology (KAIST) has built and demonstrated a new unmanned aerial vehicle (UAV) that can fly for up to ten hours using 500 grams of liquefied hydrogen fuel. The hydrogen is the energy carrier which appears to provide electricity to an electric motor via a fuel cell. At this time, the plane is piloted from the ground using radio control, but the team says that they are close to implementing an automatic pilot system, meaning that the machine would not require any manual human intervention. There is hope from the Korean team that the machine could have a future military purpose.
I've flown radio controlled airplanes before, and I can't imagine flying one for ten hours straight! After about fifteen minutes, my neck would revolt from staring up in the sky, so I'm sure that an auto-pilot would be a welcome addition.
[Source: Korean Times]