La communication entre les "U-Boot Tracking-Rooms" de Londres, de Washington, puis, à partir de 1943, de Ottawa (Canada) devint à ce point étroite que, selon les participants, elles travaillaient comme une organisation unique.
Liaison between the submarine tracking rooms in London, Washington and, from May 1943 onwards, Ottawa in Canada was so close that, according to a statement by one individual involved at the time, they worked like a single organisation.