The 1st Aircraft Carrier Squadron was a group of Royal Navy aircraft carriers assigned to the British Pacific Fleet in November 1944. They were HMS Formidable, Indomitable, Victorious, Illustrious and Indefatigable. While serving in the Pacific, within the U.S. Fifth Fleet, the squadron was designated "Task Group 57.2". During operations off Okinawa, the squadron received heavy Kamikaze attacks. Their armoured flight decks were adequate protection for the hangar decks, but the stress caused deformation of the ships' structures.[citation needed].