High Quality Content by WIKIPEDIA articles! HMS Indefatigable was an Implacable-class aircraft carrier of the British Royal Navy. Indefatigable was present at the formal surrender of the Japanese on 2 September in Tokyo Bay. She later helped to repatriate Allied POWs held in Japan and was used as a spotting ship for later US nuclear tests in the Pacific ocean. Indefatigable was scrapped in 1956.