Q:The AEG helicopter was an unusual German aircraft project intended to create a portable observation post in the form of a tethered helicopter. It achieved lift by use of two contra-rotating rotors powered by an electric motor that was supplied with power from the ground. The device could be folded for transportation on the back of a truck. An observer's cabin was suspended underneath the rotor assembly and could be blown clear by an explosive charge in case of emergency. Given a list of categories: company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, what category does the paragraph belong to?
A:
Mean Of Transportation