HMS ''Spearhead'' was a
S-class submarine of the third batch built for the
Royal Navy
The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against ...
during World War II. She survived the war and was sold to
Portugal
Portugal, officially the Portuguese Republic ( pt, República Portuguesa, links=yes ), is a country whose mainland is located on the Iberian Peninsula of Southwestern Europe, and whose territory also includes the Atlantic archipelagos of ...
. She was scrapped in 1967.
Design and description
The last 17 boats of the third batch were significantly modified from the earlier boats. They had a stronger hull, carried more fuel and their armament was revised. The submarines had a length of
overall
Overalls, also called bib-and-brace overalls or dungarees, are a type of garment usually used as protective clothing when working. The garments are commonly referred to as a "pair of overalls" by analogy with "pair of trousers".
Overalls were ...
, a
beam
Beam may refer to:
Streams of particles or energy
*Light beam, or beam of light, a directional projection of light energy
**Laser beam
*Particle beam, a stream of charged or neutral particles
**Charged particle beam, a spatially localized grou ...
of and a
draft
Draft, The Draft, or Draught may refer to:
Watercraft dimensions
* Draft (hull), the distance from waterline to keel of a vessel
* Draft (sail), degree of curvature in a sail
* Air draft, distance from waterline to the highest point on a vesse ...
of . They
displaced on the surface and submerged.
[Chesneau, p. 52] The S-class submarines had a crew of 48 officers and
ratings. They had a diving depth of .
[McCartney, p. 7]
For surface running, the boats were powered by two
diesel engine
The diesel engine, named after Rudolf Diesel, is an internal combustion engine in which ignition of the fuel is caused by the elevated temperature of the air in the cylinder due to mechanical compression; thus, the diesel engine is a so-ca ...
s, each driving one
propeller shaft
A drive shaft, driveshaft, driving shaft, tailshaft (Australian English), propeller shaft (prop shaft), or Cardan shaft (after Girolamo Cardano) is a component for transmitting mechanical power and torque and rotation, usually used to connect ...
. When submerged each propeller was driven by a
electric motor
An electric motor is an electrical machine that converts electrical energy into mechanical energy. Most electric motors operate through the interaction between the motor's magnetic field and electric current in a wire winding to generate for ...
. They could reach on the surface and underwater.
[ On the surface, the third batch boats had a range of at and at submerged.][
''Spearhead'' was armed with six 21 inch (533 mm) ]torpedo tube
A torpedo tube is a cylindrical device for launching torpedoes.
There are two main types of torpedo tube: underwater tubes fitted to submarines and some surface ships, and deck-mounted units (also referred to as torpedo launchers) installed aboa ...
s in the bow. She carried six reload torpedoes for a grand total of a dozen torpedoes. Twelve mines could be carried in lieu of the torpedoes. The boat was also equipped with a 4-inch (102 mm) deck gun
A deck gun is a type of naval artillery mounted on the deck of a submarine. Most submarine deck guns were open, with or without a shield; however, a few larger submarines placed these guns in a turret.
The main deck gun was a dual-purpose ...
.[
]
Construction and career
HMS ''Spearhead'' was laid down
Laying the keel or laying down is the formal recognition of the start of a ship's construction. It is often marked with a ceremony attended by dignitaries from the shipbuilding company and the ultimate owners of the ship.
Keel laying is one o ...
at Cammell Laird's Birkenhead
Birkenhead (; cy, Penbedw) is a town in the Metropolitan Borough of Wirral, Merseyside, England; historically, it was part of Cheshire until 1974. The town is on the Wirral Peninsula, along the south bank of the River Mersey, opposite Liver ...
shipyard on 18 August 1943, was launched on 2 October 1944 and completed on 21 December 1944. So far she has been the only ship of the Royal Navy to bear the name ''Spearhead''.HMS Spearhead
Uboat.net ''Spearhead'' survived the Second World War
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposi ...
and was sold to the Portuguese in August 1948 and renamed NRP ''Neptuno''.
Notes
References
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{{DEFAULTSORT:Spearhead (P263)
British S-class submarines (1931)
Ships built on the River Mersey
1944 ships
World War II submarines of the United Kingdom
Royal Navy ship names
British S-class submarines (1931) of the Portuguese Navy