Motor Torpedo Boat

Motor Torpedo Boat (MTB) was the name given to fast torpedo boats by the Royal Navy and the Royal Canadian Navy. The 'Motor' in the formal designation, referring to the use of petrol engines, was to distinguish them from the majority of other naval craft that used steam turbines or reciprocating engines.

The capitalised term is generally used for the Royal Navy (RN) boats and abbreviated to "MTB". During World War II the US Navy boats were usually called by their hull classification symbol of "PT" (Patrol Torpedo), and are covered under PT boat although the class type was still "motor torpedo boat".

German motor torpedo boats of World War II were called S-Boote (Schnellboote German for "fast boats") by the Kriegsmarine and E-boats by the allies. Italian MTBs of this period were known as Motoscafo Armato Silurante (MAS) which translates as "torpedo armed motorboats". French MTBs were known as Vedettes Lance Torpilles translating as "torpedo-launching fast boat". Soviet MTBs were known as Торпедный катер translating as "torpedo cutter".

After the end of World War II, a number of the Royal Navy's MTBs were stripped and the empty hulls sold for use as houseboats.