Complex sentence: On 15 October 1942, he was appointed as "Jagdfliegerführer" 3 on the Western Front, then on 6 September 1943 he was appointed as "Jagdfliegerführer" 5, responsible for the tactical fighter command of northwestern France.
Split into simpler sentences: On 15 October 1942, he became "Jagdfliegerführer" 3 on the Western Front. On 6 September 1943 he was appointed as "Jagdfliegerführer" 5, responsible for the tactical fighter command of northwestern France.