The Heinkel HD 17 was a military reconnaissance aircraft produced in Germany in the late 1920s. It was a conventional single-bay biplane with staggered wings of unequal span braced with N-type interplane struts. The pilot and observer sat in tandem open cockpits and the main units of the fixed tailskid undercarriage were linked by a cross-axle. 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