Junck's best known role in World War II is commanding "Fliegerführer Irak", the aerial component of "Sonderstab F", a military mission sent to Iraq in May 1941 to aid Rashid Ali's rebel government after it forced out the pro-British regime the previous month. On 29 May they retreated from the country. Later in the war, he led forces in the fighting against the Allied forces in Normandy. In 1960 he was appointed honorary chairman of the "Gemeinschaft der Jagdflieger", the Association of Fighter Pilots.