British 18-inch torpedo

There have been a number of 18-inch (45cm) torpedoes in service with the Royal Navy of the United Kingdom.

These have been used on ships of the Royal Navy and aircraft of both the Fleet Air Arm and Royal Air Force, while Royal Navy surface ships and submarines use 21-inch torpedoes.

The British 18-inch torpedoes were 17.72 in in diameter, beginning with the "Fiume" Whitehead torpedo of 1890.

45 cm "Fiume" (Whitehead) torpedo
First introduced into British service in 1894.
 * Year : about 1888
 * Weight : 845 lb
 * Length : 11 ft
 * Warhead : 118 lb wet gun-cotton
 * Performance : 26.5 kn for 800 yd
 * Propulsion : Compressed air

Mark V
Used on the River-class and 1905 Tribal-class destroyers.


 * Year : about 1899
 * Weight : 1353 lb
 * Warhead : 296 lb including pistol
 * Propulsion : Compressed air

Mark VI
Used on destroyers of the early 1900s.


 * Year : about 1904
 * Performance : 28.5 kn for 4000 yd or 41 kn for 1000 yd
 * Propulsion : Compressed air

Mark VII and VII*
Introduced on the 1908 members of the 1905 Tribal class destroyers. Used by torpedo boats built before the First World War and destroyers. Used by RAF flying boats in the 1920s.

30 kn for 6000 - 7000 yd 41 kn for 3000 yd 29 kn for 7000 yd 35 kn for 5000 yd
 * Year : 1907
 * Warhead : 320 lb TNT
 * Performance :
 * Mark VII :
 * Mark VII* :
 * Propulsion : Wet-heater

Mark VIII

 * Year: 1913
 * Role: Submarines and aircraft (Note: During World War II and after the Mk.VIII was a 21-inch torpedo)
 * Warhead: 320 lb TNT
 * Propulsion: Wet heater
 * Performance: 35 kn for 2500 yd

Mark XI

 * Year: 1934
 * Aircraft carried
 * Dimensions: 17.72 in dia.
 * Warhead: 465 lb TNT
 * Propulsion: Burner cycle
 * Performance: 35 kn for 2500 yd

Mark XII
Aircraft launched, used by Fleet Air Arm and RAF Coastal Command.

Mark XIV
The Mark XIV was an aircraft-launched torpedo. Stocks were lost with the fall of Singapore.

Mark XV

 * Year: 1942
 * Operators: Fleet Air Arm, RAF Coastal Command, Royal Navy
 * Role: Aircraft and Motor Torpedo Boats, 1943 onwards
 * Dimensions: 17.69 in × 17 ft
 * Warhead: 545 lb Torpex
 * Propulsion: Burner cycle
 * Performance: 40 kn for 2500 yd or 33 kn for 3200 yd

Mark XVI
Electric torpedo project not completed.

Mark XVII

 * United Kingdom, 1944
 * Aircraft launched
 * Operated by FAA, RAF Coastal Command, Blackburn Firebrand
 * Dimensions: 17.72 in × 17 ft
 * Warhead: 600 lb Torpex
 * Propulsion: Burner cycle
 * Performance: 40 kn for 2500 yd

Mark 30
An air-dropped passive acoustic homing torpedo known as "Dealer" and "Dealer B".


 * Length: 8 ft
 * Weight: 646 lb
 * Performance: 12.5 kn for 3000 yd or 19 kn for 830 yd