Operation Mosaic Captain Hugh Martell would be in charge as commander Task Force 308, with the temporary rank of commodore. Charles Adams from Aldermaston, who had been the deputy technical director to Leonard Tyte for Operation Hurricane and to William Penney on Operation Totem, was appointed the scientific director for Operation Mosaic, with Ieuan Maddock as the scientific superintendent. Group Captain S. W. B. (Paddy) Menaul would command the Air Task Group. Menaul was also a nuclear test veteran, having been an observer on board Vickers Valiant WZ366 when it had made the first operational drop of a British atomic bomb during
Operation Sandstone at Los Alamos on July 9 to make arrangements for the tests. They readily agreed that they would be scientific in nature, with Los Alamos supplying the technical direction and the armed forces providing supplies and logistical support. The cost of the tests, around $20 million, was divided between the Department of Defense and the Atomic Energy Commission. Lieutenant General John E. Hull was designated as test commander. Rear Admiral William S. Parsons and Major General William E. Kepner reprised their Operation Crossroads roles as deputy commanders. Joint Task Force 7 was formally activated on October 18, 1947. As its