On his return to London, Admiral Noble was appointed Commander-in-Chief, Western Approaches, headquartered at Derby House, Liverpool, from February 1941 to November 1942. His work in reorganising escort groups, and revamping escort training methods are widely regarded as having been crucial foundational elements of the eventual success of the Allied navies in the Atlantic theatre. Noble was remembered by those who worked with him at Derby House as an easy-going commander, and an agreeable person to work with. Always conciliatory, Noble was an expert at building consensus around his chosen courses of action. Noble was, although not forced, certainly pushed out of Western Approaches to make room for Admiral Sir Max Horton, whose combative personality and experience in the submarine service made him the ideal candidate in the eyes of some to take the war to the U-boats.