Hermann-Friedrich Joppien (19 July 1912 – 25 August 1941) was a German Luftwaffe military aviator during World War II, a fighter ace who claimed 70 enemy aircraft shot down in roughly 270 combat missions. He claimed 42 victories over the Western Front, of which 23 were Supermarine Spitfires, the remaining victories were recorded over the Eastern Front. Born in Bochum, Joppien volunteered for military service, at first with the Reichswehr of the Weimar Republic and later with the Luftwaffe of Nazy Germany. He was posted to Jagdgeschwader 51 (JG 51—51st Fighter Wing) in 1939 and fought in the Battle of France and Britain on the Western Front. In October 1940 he was given command of I. Gruppe (1st group) of JG 51. On account of his 40th aerial victory claimed, he was awarded Knight's Cross of the Iron Cross with Oak Leaves. It was Germany's highest military decoration at the time of its presentation to Joppien. Fighting on the Eastern Front, he was killed in action with Soviet fighters on 25 August 1941. Early life and career Joppien was born on 19 July 1912 in Bochum in the Province of Westphalia, a province of the Kingdom of Prussia. His father was a laborer and when he found new work in 1917, the family moved to Hersfeld. After Joppien completed his schooling, he received a vocational education and learned the trade of a typesetter in a printing firm. In October 1931, Joppien joined the military service with Infanterie-Regiment 15 (15th Infantry Regiment) of the Reichswehr of the Weimar Republic in Gießen. There he was promoted to Unteroffizier (corporal) in 1933. In parallel to his military service at Gießen, Joppien was very much interested and involved in glider construction and glider flight. His transfer to the Luftwaffe was somewhat delayed as Joppien had been tasked with the training of new officer recruits. On 15 October 1935, his transfer to the Luftwaffe was finally authorized. Until Christmas 1935, he had logged 100 solo flights and in June 1936 he became a flight instructor. He was promoted to Unterfeldwebel (junior non-commissioned officer) on 1 October 1936, to Feldwebel (non-commissioned officer) on 1 February 1937, and to Oberfeldwebel (staff sergeant) on 1 July 1937. He was then selected for officer training and posted to a Kriegsschule (war school). Graduating among the top of his class of 130 students, he was promoted to Leutnant (second lieutenant)