On 26 July, she sortied for the Norwegian Sea as part of Operation Governor, together with the battleship , the American battleship , and the light carrier , an attempt to fool the Germans into thinking that Sicily was not the only objective for an Allied invasion. 810 Squadron was the only unit retained from her previous air group and it had been re-equipped with Barracudas during her refit. Her fighter complement was augmented by 878 and 890 Squadrons, each with 10 Martlet Vs, and 894 Squadron with 10 Seafire IICs. These latter aircraft lacked folding wings and could not fit on the lifts. The British ships were spotted by Blohm & Voss BV 138 flying boats and 890 Squadron shot down two of them before the fleet returned to Scapa Flow on 29 July. She transferred to Greenock at the end of the month and sailed on 5 August to provide air cover for the ocean liner as she conveyed Prime Minister Winston Churchill to the Quebec Conference. Once the convoy was out of range of German aircraft, the "Illustrious" left the convoy and arrived back at Greenock on 8 August.