After the Italian invasion, his squadron was sent to Greece in November 1940, where Pattle achieved most of his victories. Pattle claimed around 20 aircraft shot down and in March 1941 was promoted to squadron leader. After the German intervention, and in fourteen days of operations, Pattle claimed . Pattle claimed five or more aircraft destroyed in one day on three occasions, which qualified him for ace in a day status. Pattle achieved his greatest success on 19 April 1941, claiming six victories. The following day, having claimed more aerial victories than any other Western Allied pilot, he took off against orders, while suffering from a high temperature, to engage German aircraft near Athens. He was last seen battling Messerschmitt Bf 110 heavy fighters. His Hurricane crashed into the sea during this dogfight and Pattle was killed.