Pick one category for the following text. The options are - company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work. Aeronautica Umbra Trojani AUT.18 -  The AUT.18 was a prototype fighter aircraft developed in Italy by Aeronautica Umbra shortly before the outbreak of World War II. It was designed in 1934 by Ing Felice Trojani who at that time was collaborating with Umberto Nobile on the Arctic flights of the airships Norge and Italia. The aircraft's designation came from initials of the manufacturer the surname of the designer and the aircraft's wing area (18 m²) the sole prototype receiving the serial no. M.M.363.
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