Submarine Snorkel
   HOME

TheInfoList



OR:

A submarine snorkel is a device which allows a
submarine A submarine (or sub) is a watercraft capable of independent operation underwater. It differs from a submersible, which has more limited underwater capability. The term is also sometimes used historically or colloquially to refer to remotely op ...
to operate submerged while still taking in air from above the surface. British Royal Navy personnel often refer to it as the snort. A concept devised by Dutch engineers, it was widely used on German
U-boat U-boats were naval submarines operated by Germany, particularly in the First and Second World Wars. Although at times they were efficient fleet weapons against enemy naval warships, they were most effectively used in an economic warfare ro ...
s during the last year of
World War II 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 World War II by country, vast majority of the world's countries—including all of the great power ...
and known to them as a ''Schnorchel''.


History

Until the advent of
nuclear power Nuclear power is the use of nuclear reactions to produce electricity. Nuclear power can be obtained from nuclear fission, nuclear decay and nuclear fusion reactions. Presently, the vast majority of electricity from nuclear power is produced b ...
, submarines were designed to operate on the surface most of the time and submerge only for evasion or for daylight attacks. Until the widespread use of
radar Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, Marine radar, ships, spacecraft, guided missiles, motor v ...
after 1940, at night a submarine was safer on the surface than submerged, because
sonar Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, measure distances (ranging), communicate with or detect objects on o ...
could detect boats underwater but was almost useless against a surface vessel. However, with continued radar improvement as the war progressed, submarines (notably, the
German German(s) may refer to: * Germany (of or related to) **Germania (historical use) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizens of Germany, see also German nationality law **Ge ...
U-boats U-boats were naval submarines operated by Germany, particularly in the First and Second World Wars. Although at times they were efficient fleet weapons against enemy naval warships, they were most effectively used in an economic warfare rol ...
in the Battle of the Atlantic) were forced to spend more time underwater, running on electric motors that gave speeds of only a few knots and very limited range. An early submarine snorkel was designed by James Richardson, an Assistant Manager at
Scotts Shipbuilding and Engineering Company Scotts Shipbuilding and Engineering Company Limited, often referred to simply as Scotts, was a Scottish shipbuilding company based in Greenock on the River Clyde. In its time in Greenock, Scotts built over 1,250 ships. History John Scott fo ...
, Greenock, Scotland as early as 1916, during
World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...
. Although the company received a British patent for the design, no further use was made of it—the British Admiralty did not accept it for use in 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 F ...
. In November 1926 Capt. Pericle Ferretti of the technical corps of the Italian Navy ran tests with a ventilation pipe installed on the submarine ''H 3''. The tests were largely successful, and a similar system was designed for the ''Sirena'' class, but was eventually scrapped; subsequent snorkel systems were not based on Ferretti's design. Germany defeated the Netherlands in 1940; their capture of ''O-25'' and ''O-26'' was a stroke of luck for the German Navy, the ''
Kriegsmarine The (, ) was the navy of Germany from 1935 to 1945. It superseded the Imperial German Navy of the German Empire (1871–1918) and the inter-war (1919–1935) of the Weimar Republic. The was one of three official branches, along with the a ...
''. The Dutch '' O-21 class'' were equipped with a device named a ''snuiver'' (''sniffer''). The Royal Netherlands Navy had been experimenting as early as 1938 with a simple pipe system on the submarines ''O-19'' and ''O-20'' that enabled diesel propulsion at
periscope depth A periscope is an instrument for observation over, around or through an object, obstacle or condition that prevents direct line-of-sight observation from an observer's current position. In its simplest form, it consists of an outer case with ...
, while also charging the batteries. The system was designed by the Dutchman Jan Jacob Wichers. The Kriegsmarine first viewed the snorkel as a means to take fresh air into the boats but saw no need to run the diesel engines under water. However, by 1943 more U-boats were being lost, so the snorkel was retrofitted to the VIIC and IXC classes and designed into the new XXI and XXIII types. The first Kriegsmarine boat to be fitted with a snorkel was ''U-58'', which experimented with the equipment in the
Baltic Sea The Baltic Sea is an arm of the Atlantic Ocean that is enclosed by Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, Sweden and the North and Central European Plain. The sea stretches from 53°N to 66°N latitude and from ...
during the summer of 1943. Operational use began in early 1944, and by June 1944 about half of the boats stationed in the French bases had snorkels fitted. On
Type VII U-boat Type VII U-boats were the most common type of German World War II U-boat. 703 boats were built by the end of the war. The lone surviving example, , is on display at the Laboe Naval Memorial located in Laboe, Schleswig-Holstein, Germany. Co ...
s the snorkel folded forward and was stored in a recess on the port side of the hull, while on the IX Types the recess was on the starboard side. The XXI and XXIII types both had telescopic masts that rose vertically through the conning tower close to the periscope.


Operational limitations

Although snorkels allowed submarines to use their diesel engines while submerged, their use had limitations and problems. U-boats with their snorkels raised were limited to six knots to avoid damaging or breaking the tube. The ''
Gruppenhorchgerät The ''Gruppenhorchgerät'' ('group listening device', abbreviated GHG) was a hydrophone array which was used on Nazi Germany's U-boats in World War II. Development In World War I carbon microphones were still used as sound receivers. The individu ...
'' (the boat's
hydrophone A hydrophone ( grc, ὕδωρ + φωνή, , water + sound) is a microphone designed to be used underwater for recording or listening to underwater sound. Most hydrophones are based on a piezoelectric transducer that generates an electric potenti ...
array An array is a systematic arrangement of similar objects, usually in rows and columns. Things called an array include: {{TOC right Music * In twelve-tone and serial composition, the presentation of simultaneous twelve-tone sets such that the ...
) was useless while running diesel engines submerged. However, the most dramatic effect caused by the use of snorkels was their ability to create partial vacuums within the submarine. Early snorkels had automatic
ballcock A ballcock (also balltap or float valve) is a mechanism or machine for filling water tanks, such as those found in flush toilets, while avoiding overflow and (in the event of low water pressure) backflow. The modern ballcock was invented by Jos ...
valves fitted (to prevent seawater from waves being sucked into the diesel engines) that could slam shut in rough weather, forcing the engines to rapidly draw air from within the boat itself. The sudden reduction in pressure would cause the crew to experience extreme pain in their ears, occasionally causing ruptured eardrums.
Atmospheric pressure Atmospheric pressure, also known as barometric pressure (after the barometer), is the pressure within the atmosphere of Earth. The standard atmosphere (symbol: atm) is a unit of pressure defined as , which is equivalent to 1013.25 millibars, ...
would then hold the ballcock valve firmly shut, forcing the boat to shut down its diesel engines and surface. The engineering problem still exists in modern submarines; however, the effect is mitigated with the use of high-vacuum cut-off sensors that shut down the submerged boat's engines when any sudden pressure drop is detected. Likewise, modern snorkels have a fail-safe design. An electrical circuit controls a compressed air system that holds a "head valve" open against the pull of a powerful spring. When waves wash over exposed contacts, the control circuit breaks, venting the compressed air, causing the head valve to slam shut. The valve is immediately reopened by compressed air when the contacts are again clear of the water. As snorkels were designed to draw in and vent gases, a submarine's
diesel exhaust Diesel exhaust is the gaseous exhaust produced by a diesel type of internal combustion engine, plus any contained particulates. Its composition may vary with the fuel type or rate of consumption, or speed of engine operation (e.g., idling or at ...
could be seen on the surface up to a distance of about . Also, "periscope feather" (the wave created by the snorkel or periscope moving through the water) can be spotted in calm seas. During the early months of the Battle of the Atlantic in World War II, British ships using the radar set Model 271 were able to detect the periscope of a submerged submarine at a distance of during tests in 1940.


See also

*


References


Notes


Further reading

*
"New Subs Are Undersea Aircraft"
June 1949, ''
Popular Science ''Popular Science'' (also known as ''PopSci'') is an American digital magazine carrying popular science content, which refers to articles for the general reader on science and technology subjects. ''Popular Science'' has won over 58 awards, incl ...
'': detailed drawing at bottom of page 102 explaining the new ''Guppy'' class's snorkel system * {{Authority control Submarine_components Submarine design Dutch inventions