Allan Rockwell McCann was in charge of the development of a submarine rescue chamber, which bears his name, "The McCann Submarine Rescue Chamber". Additionally he was assigned as Liaison Officer / Engineer when the submarine was converted for use in the under ice attempt to circumnavigate the Arctic Ice cap and voyage to the North Pole. Modifications to the submarine were extensive, and contained innovations of a telescoping conning tower, an ice drill, an incorporated diving bell and an Air Lock, designed by Simon Lake. The submarine was designated "Nautilus" and leased for one dollar to Lake and Danenhower, Inc., of Bridgeport, Connecticut,
Nuclear weapons and the United Kingdom remain classified. Much of the HEU supplied by the US was used not for weapons, but as fuel for the growing fleet of UK nuclear submarines. Under the MDA, the US supplied the UK with not just nuclear submarine propulsion technology, but a complete S5W pressurised water reactor of the kind used to power the US submarines. This was used in the Royal Navy's first nuclear-powered submarine, , which was launched in 1960 and commissioned in 1963. The S5W had a Nuclear reactor core that used uranium enriched to between 93 and 97 per cent uranium-235. Reactor technology was transferred