The two ''Explorer''-class submarines were experimental vessels built for the

Royal Navy The Royal Navy (RN) is the naval warfare force of the United Kingdom. It is a component of His Majesty's Naval Service, and its officers hold their commissions from the King of the United Kingdom, King. Although warships were used by Kingdom ...

to test a propulsion system based on the use of highly concentrated hydrogen peroxide (

high-test peroxide High-test peroxide (HTP) is a highly concentrated (85 to 98%) solution of hydrogen peroxide, with the remainder consisting predominantly of water. In contact with a catalyst, it decomposes into a high-temperature mixture of steam and oxygen, with n ...

, HTP) and

diesel fuel Diesel fuel, also called diesel oil, heavy oil (historically) or simply diesel, is any liquid fuel specifically designed for use in a diesel engine, a type of internal combustion engine in which fuel ignition takes place without a spark as a re ...

to achieve high underwater endurance and speeds. Germany had started experimenting with this technology early in the

Second World War World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

and developed it into the

Walter Walter may refer to: People and fictional characters * Walter (name), including a list of people and fictional and mythical characters with the given name or surname * Little Walter, American blues harmonica player Marion Walter Jacobs (1930–19 ...

cycle. They had built some experimental boats. One of these, the Type XVII ''U-1407''

U-boat U-boats are Submarine#Military, naval submarines operated by Germany, including during the World War I, First and Second World Wars. The term is an Anglicization#Loanwords, anglicized form of the German word , a shortening of (), though the G ...

submarine, which had been scuttled at the end of the war, was salvaged and eventually recommissioned into the

as . This eventually led to the construction of the two ''Explorer''-class experimental

submarine A submarine (often shortened to sub) is a watercraft capable of independent operation underwater. (It differs from a submersible, which has more limited underwater capability.) The term "submarine" is also sometimes used historically or infor ...

boats, which used

steam turbine A steam turbine or steam turbine engine is a machine or heat engine that extracts thermal energy from pressurized steam and uses it to do mechanical work utilising a rotating output shaft. Its modern manifestation was invented by Sir Charles Par ...

s, the steam being generated using heat from the catalysed interaction of HTP and diesel oil. They used the ''Porpoise''-class hull, modified with retractable superstructure fittings to help streamlining. Being purely experimental craft they had no torpedo tubes or radar fitted, only one periscope and were equipped with backup diesel engines to recharge the batteries and propel them on the surface.Miller & Jordan, p. 63 The first, ''Excalibur'', was commissioned in March 1958. They were very fast boats, achieving a peak speed of over 30 knots, a speed record at the time for a submarine, a sustained underwater speed of around for period up to 3 hours, and for 15 hours on one turbine. Because of the use of hydrogen peroxide as a

hair bleach Hair bleaching is the practice of lightening the hair color, mainly for cosmetic purposes using bleaching agents. Bleaching can be done alone, combined with a toner, or as a step for further hair coloring. The most common commercial bleaching age ...

, the submarines were nicknamed the ''Blonde'' class. As well as providing experience with this type of technology, they also allowed the Royal Navy to practise against fast moving underwater targets. However the use of HTP was not successful, and there were several explosions, which resulted in the second nickname of ''Exploder'' being applied to the class and ''Explorer'' in particular, while ''Excalibur'' had the nickname "Excruciater". The subsequent use of HTP to power torpedoes led to the loss of and the loss of the . When the United States developed a

nuclear reactor A nuclear reactor is a device used to initiate and control a Nuclear fission, fission nuclear chain reaction. They are used for Nuclear power, commercial electricity, nuclear marine propulsion, marine propulsion, Weapons-grade plutonium, weapons ...

which could be installed in a submarine, the HTP project was abandoned. It was decided that it was not worth converting the class into normal diesel submarines. As a result, ''Explorer'' was sold for £13,500 to

Thos. W. Ward Thos. W. Ward Ltd was a Sheffield, Yorkshire, business primarily working steel, engineering and cement. It began as coal and coke merchants. It expanded into recycling metal for Sheffield's steel industry, and then the supply and manufacture ...

for breaking up; ''Excalibur'' in turn was also subsequently sold to Thos. W. Ward.. Retrieved 7-3-2009. Other countries have since developed the concept of the non-nuclear

air-independent propulsion Air-independent propulsion (AIP), or air-independent power, is any marine propulsion technology that allows a non-nuclear submarine to operate without access to atmospheric oxygen (by surfacing or using a snorkel). AIP can augment or replace th ...

submarine to the point where it is a safe technology albeit as an auxiliary power source to a conventional diesel-electric drive, although hydrogen peroxide has long been abandoned and liquid oxygen is generally now preferred.

Boats

References

Bibliography

* * {{UK submarine classes after 1945 Submarine classes