The Junkers J.1 was a German fighter aircraft developed during World War I. It was notable for its all-metal construction, which was innovative for its time. The aircraft featured a distinctive parasol wing design and was powered by a Junkers L.5 engine, allowing it to reach speeds of around 200 km/h. First flown in 1917, the J.1 was primarily used for reconnaissance and ground attack missions. Although it had a limited production run, its design influenced future aircraft, showcasing the potential of metal airframes in aviation. The J.1 remains an important example of early 20th-century aircraft engineering.