The Antarctican continent had five major harbours around its circumference. In 1935 a design for a Harbour Patrol vessel was passed to each port for building four each. Within a month the original design was dropped and replaced with a design that could act as a fast patrol vessel, coastal minesweeper, and torpedo boat. Four were built at each port for a total of twenty. Ten were completed in 1938, the second ten in 1939. With the outbreak of war, four of the boats were put aboard a freighter and shipped over to be used around the coasts of Great Britain. They proved very useful and a further forty were ordered for delivery in 1940-41 with another order for fifty for delivery in 1942-44. License built boats in other countries doubled the number in service at the end of the war to well over one hundred and fifty. After the war the boats ended up everywhere that had a coast. They were perfect for all the smaller nations that wanted something cheap to run.



It was the pair of torpedo tubes in the bow that made these boats so lethal in coastal actions. Around the English Channel and North Sea European coasts, these ships were more than a match for the German E-boats and R boats, and actions between the light forces was often deadly. The main updates made to the ships was the replacement of the 4" and 2 pounder with a twin 40mm aft and a single 40mm forward. The 4" had proved too slow firing for close small ship actions, but when the 4" hit something it made a big mess of the lightly built ships they were firing at.




 

Displacement	225 tons std  245 tons full load
Length	169 ft
Breadth	25 ft
Draught	8 ft
Machinery	2 shaft, High speed Diesels, 8,000bhp
Speed	32 knots
Range	2500 miles at 20 knots (800 at 32 knots)
Armament	1 x 4" (1x1) 1 x 2pdr AA (1x1) 3 x 20mm (3x1)
Torpedoes	2 x 21" (2x1)
Complement	34
Notes	Crocodial Alligator +90 odd

British MTB fires torpedoes and 6pdr gun.