TID was a standardized British design for a tugboat drawn up and built during the Second World War.
Richard Dunston Ltd., a shipbuilding company with yards at Thorne on the Stainforth and Keadby Canal and at Hessle on the Humber, had pioneered the use of welded construction, rather than the more conventional rivetting, since 1933, although they had never built an all-welded vessel.
[1] They designed the hulls so that they could be made up from eight separate sections, which were fabricated by manufacturers with spare welding capacity.
Shipbuilders with spare capacity were in short supply at the time, but other non-shipbuilding industry was available.
Propulsion was a 220 ihp 2 cylinder reciprocating steam engine driving a single screw.