Karl Borris (3 January 1916 – 18 August 1981) was a World War II Luftwaffe military aviator and test pilot. As a flying ace, he is credited with 43 victories, all of them over the Western Front, for which he was awarded the Knight's Cross of the Iron Cross, the highest award in the military and paramilitary forces of Nazi Germany during World War II. Borris was involved in the introduction of the Focke-Wulf Fw 190 to front line service. Borris and 30 other pilots, technicians and engineers extensively tested the Fw 190 and their input was used in the decision to continue the project. World War II World War II in Europe began on Friday 1 September 1939 when German forces invaded Poland. On 1 December 1939, Leutnant Borris joined Jagdgeschwader 26 "Schlageter" (JG 26—26th Fighter Wing), which had been named after Albert Leo Schlageter on 1 May 1939. There, he was assigned to II. Gruppe (2nd group). At the time, the Geschwader was commanded by Oberst Eduard Ritter von Schleich and II. Gruppe was led by Hauptmann Herwig Knüppel. The Gruppe was based at Werl and patrolled western German border during the "Phoney War" without having contact with the enemy. On 27 January, II. Gruppe was ordered to Dortmund where it stayed until 9 May 1940. During the Battle of France on 13 May, Borris was shot down in his Messerschmitt Bf 109 E-3 by a Boulton Paul Defiant fighter near Dordrecht. He managed to bail out, was injured and returned to his Staffel on 17 May. According to Mathews and Foremann, his victor was either Flight Lieutenant Ken Gillies from No. 66 Squadron or Pilot Officer P.E.J. Greenhous from No. 264 Squadron. Prior to this mission, Borris had attended a gas-protection course in Berlin. Command of II. Gruppe changed frequently in 1940. On 19 May, Knüppel was killed in action, he was temporarily replaced by Hauptmann Karl Ebbinghausen until he was appointed Staffelkapitän (squadron leader) of 4. Staffel on 31 May. On 1 June, command of II. Gruppe was officially handed over to Hauptmann Erich Noack. Noack was killed in a landing accident on 24 July, and command of II. Gruppe was again given to Ebbighausen, who was then killed in action on 16 August. Hauptmann Erich Bode then led the Gruppe until 3 October when Hauptmann Walter Adolph was given command. Boris claimed his first aerial