How the first ultra-small submarine of the USA was created

Americans worried that they would be outpaced by the RussiansUnlike a number of other countries of the world that made a big bet on the creation of small and ultra-small submarines (submarines), the command of the American Naval Forces in the second half of the twentieth century focused on the development of a powerful nuclear submarine fleet, gradually abandoning the construction of diesel-electric submarines.

Well, the direction of "babies" was considered unpromising at all.

As a result of this approach, only a limited number of group underwater carriers of the SDV family eventually entered service with the American naval special forces. And the ultra-small submarine (SMPL) X-1 remained in a single copy and was in operation as an experimental warship for a very short time.

THE DEVIL IS NOT AS SCARY AS HIS LITTLE ONESAfter the Second World War, the allies in the anti-Hitler coalition shared the spoils of the defeated Reich.

Among them, a special place was occupied by structurally very interesting SMPLS of the type "Seehund" (Seehund, "Seal").

In the hands of the Anglo-American allies and France, there were a total of 93 unfinished Seehunds, as well as a number of combat-ready mini-submarines of this type. French sailors even introduced several of them into the combat structure of their Navy. Several such SMPLS in varying degrees of readiness also went to the Soviet Union. It is believed that there were from two to six of them, although American intelligence agencies operated with different data.

In May 1948, American military intelligence published a report claiming that their colleagues, Soviet intelligence officers, had captured 18 ready-made "Zeehunds" and another 38 unfinished ones. Pentagon analysts and anti-submarine warfare experts of the US Navy expressed fears that the USSR Armed Forces could put all these combat submarines into operation, which would pose a serious potential threat to US national security. It was assumed that the Soviet Navy could use these captured mini-submarines to carry out reconnaissance and sabotage operations against American naval bases and ports.

Their colleagues from the CIA went even further in whipping up underwater hysteria, who in a secret message dated November 27, 1957 (a censored version of it was made public only in 2013) claimed that the Soviet Navy has "at least 70 ultra-small submarines, of which most are considered to be combat-ready." At the same time, the tsereushniki seriously noted that the enemy "should have" about 20 mini-submarines of the Seehund type and about fifty SMPLS of an incomprehensible Soviet type.

"Soviet ultra-small submarines built after 1947 are an improved version of the previous type and were created using the technical documentation of the German (SMPL) type "Seehund", – it was indicated with genuine alarm in this message.

The document also cited the main tactical and technical elements of the Seehund type SMPL, allegedly entered service with the Soviet Navy: dimensions - 12.20 × 1.9 × 1.8 m; displacement – 15.2–16.5 tons; main power plant – one 60–horsepower diesel, one electric motor and one propeller; surface speed - 5 knots, underwater – 4 knots; surface navigation range – 500 miles, underwater - 60 miles; armament – two 533-mm torpedoes placed outside the strong hull; crew – three people; "use of magnetic or non–magnetic materials - no data"; "equipment with demagnetizing equipment – no data"; "fitness for towing – maybe."

Today it is known for certain that we did not have any SMPLS of our own construction in those years, and "dozens" of German mini-submarines did not get to us. Although Soviet specialists took at least two, and at most six SMPLS out of Germany. But in the end, only one significantly modified trophy mini-submarine entered the combat structure of the Soviet Navy.

I will add that, judging by the number of the above–mentioned tsereushny message, which contains the designation HUM (cf. human intelligence - agent intelligence), it was prepared on the basis of a report from a scout or a recruited agent. It is unclear where this scout or spy got fabulous information, except in some Soviet rummy. Apparently, the "Soviet tracked submarines" are also from there, traces of which have been found by Swedish sailors in their territorial waters for many decades.

But the main thing was done – panic was sown in the hearts and minds of American politicians. And the response was not long in coming.

EXPERIMENTS WITH MINI-SUBMARINESImmediately after the end of World War II, the OSS (the Office of Strategic Services – the predecessor of the CIA) carried out a large-scale program of studying captured samples of weapons, military equipment and equipment for the possibility of their use in the interests of American intelligence services.

Including overseas "knights of the cloak and dagger" conducted tests of ultra-small submarines.

Among them there was one perfectly serviceable SMPL of the Seehund type with the tactical number U-5075. She was brought to the United States in 1945 and, after long wanderings, found refuge in the exposition of the US Naval Shipbuilding Museum in Quincy, Massachusetts.

Soon the scouts were joined by sailors, who were also interested in such a "miracle weapon". In particular, in the summer of 1950, a British SMPL with the tactical number HE7 arrived at the Norfolk Naval Base. It was a mini-submarine of the "HE" type – an improved version of the "X" type SMPL. She went through an intensive pilot operation program in America.

In addition, in order to study the effectiveness of the anti-submarine and anti-sabotage defense system of the ports and bases of the US Navy on the east coast of the country, the Americans used "Zeehunds", taken, as they say now, "on lease" from the French Navy. In 1953, the command of the US Navy sent a request to the French Navy about the possibility of secondment to the Pentagon of two Seehund-type submarines that were in the combat composition of the French fleet. Paris agreed and allocated the S-622 and S-623 super-currencies to the Americans.

For two years, the crews of these mini-submarines conducted training torpedo attacks. And all of them turned out to be, to the great surprise of the US Navy command, successful! According to the results of the evaluation of the tests, American experts made two important conclusions:

– firstly, the security system of the country's ports and even naval bases was recognized as useless and required serious reworking, especially in light of the emerging confrontation with the former partner in the anti-Hitler coalition – the Soviet Union;

– secondly, it was found that SMPLS have a very high combat potential, as a result of which they require closer attention and deserve to be adopted by the US Navy.

After analyzing the design features of the German Seehund-type SMPLS, as well as summarizing the results of their experimental operation by special forces and US Navy intelligence, the command of the latter came to the conclusion that it was necessary to continue work in this area. And the creation of a sample of naval equipment of a similar class, but already completely national design and construction.

The design organizations were given a tactical and technical task for the creation of an experimental SMPL for special purposes. It had to be designed, built, subjected to comprehensive tests and then handed over to the navy.

As a result of this work, the first ultra-small submarine in the history of the US Navy was born.

SECRET SUBMARINEThe promising experimental SMPL of special purpose received the designation X-1.

At the same time, the abbreviation SS – from Submarine Studies ("research in the field of underwater shipbuilding") was used as a prefix to its name.

This designation had its own meaning. It was assumed that this was an experimental or experimental submarine for conducting various studies, and not for combat duty. At the same time, it should be noted that since the super-small was never included in the combat composition of the US Navy, the abbreviation USS (United States Ship) was not officially applied to it, and if you see such a designation somewhere, you know – this is a mistake.

The order for the construction of the SMPL was issued to the US Navy on October 31, 1952. And on June 8, 1954, it was laid down at the enterprise of the engine-building division of the Fairchild Engine and Airplane Corporation. This company was located in the Deer Park area on Long Island, New York.

Judging by the data cited in foreign sources, then the mini-submarine was completed at the Jakobson Shipyard Inc. This shipyard in 1926-1938 was located in Brooklyn, New York (the company was then called Jakobson & Petersen), and in 1938-1984 - in the town of Oyster Bay, famous for the fact that the 26th US President Theodore Roosevelt died here in 1919. The city of Oyster Bay stands on the southern coast of the Bay of the same name. In turn, Oyster Bay is located on the north coast of Long Island Island in the same state of New York.

Interestingly, there is no information on the construction number X-1 in the documents of this shipyard, according to foreign researchers. Perhaps it was not assigned to her – because of the initial "incomprehensibility" of this peculiar order.

On September 7, 1955, X-1 was launched in the waters of the Jakobson Shipyard, and on October 6 was officially transferred to the US Navy in New London, Connecticut. On October 7, SMPL X-1 under the command of Lieutenant Kevin Hanlon began trial operation as part of the Navy.

The first crew of the mini-submarine included:

– Commander R.K. McLean – representative of the command of the 82nd Division of submarines of the US Navy, senior on board;

– Lieutenant Kevin Hanlon – Commander of the SMPL;

– Chief Petty Officer-Motorist Charles Jones;

– Petty Officer 1st Class - motorist Kenneth Andrew;

– Petty Officer 3rd class - motorist Charles Annable;

– Petty Officer 1st Class - electrician Jack Roberts.

Already in the February 1956 issue of Popular Mechanics magazine, a note appeared "The Navy is testing the first ultra-small submarine as a melee weapon" (Navy Tests the First Midget Submarine As Close-In Weapon). The note was dedicated to the X-1 and contained quite a decent, apparently, not even a retouched photo of the new American "miracle weapon".

Among other things, the note indicated that the construction of a new American super-small was carried out "in an aircraft hangar." Which, in the author's opinion, quite unambiguously confirms the above information that the laying and construction of the SMPL was carried out in the workshop in the Deer Park area, and the completion and launching were then carried out at the Jakobson Shipyard.

DESIGN FEATURESThe super-small X-1 had the following main tactical and technical characteristics: surface / underwater displacement – 31.5 / 36.3 tons; maximum payload weight – 2 tons; length – 49 feet 6 inches (15.09 m), width – 7 feet (2.13 m), draft amidships – 6 feet 2 inches (1.89 m), the maximum navigational draft is 7 feet (2.13 m).

The full-time crew of the mini-submarine included five people led by the commander (this was the only officer on the submarine). But a number of sources claim that in addition to the crew, a reconnaissance and sabotage group consisting of four or five servicemen - combat swimmers or light divers - could be placed on the mini–submarine. However, this is apparently a mistake.

American sources indicate that during the tests of the X-1, the crew, increased to six people, could barely fit on board. Where as many as ten people could be accommodated there, that is, the crew and the special group, and even with weapons and equipment, is not entirely clear. There is no place provided for the placement of the special group on the X-1 scheme given in the literature.

As for weapons, they were absent on the X-1, excluding personal weapons and military equipment of the special group's servicemen.

The body of the super-small had a well-streamlined spindle-shaped shape and was assembled from several sections. Almost all along its upper part, a superstructure was built, in the middle part of which there was a small cabin – a fence of retractable devices.

Closer to the bow in the hull of the mini-submarine there was an entrance hatch and a structure covering it, which was used as a breakwater shield on the move in the surface position.

In the lower part of the X-1 case, a kind of "hump" was arranged, in the middle part of which, judging by the scheme available to the author, there were batteries. While its front part was used as a safety, shockproof fairing, and the back was filled with water.

The aft tail is cruciform, with vertical and horizontal two–section rudders and a five-bladed propeller. The bow horizontal rudders initially on the mini-submarine, apparently, were absent. At least they are not mentioned anywhere, and they are not visible in any of the photographs of the first period of the X-1's existence. But subsequently, small horizontal bow rudders were installed in the bow of the superstructure, in front of the entrance hatch, on a structure specially added for this purpose.

Inside, the X-1 body was structurally divided into two compartments. The first of them was inhabited. There was an airlock (exit to the starboard side), the crew and control devices of the submarine. In particular, the instruments of the hydroacoustic system and/or echo sounder, the SMPL motion control panel and the operation control of the main power plant, as well as the equipment of the air conditioning system were located in the bow compartment.

At the same time, after repair and modernization (this will be discussed below), the front part of the bow compartment was divided into two tiers using a platform: there was an airlock on the lower one, and on the upper one there were places for personnel to rest, a battery, compressed air cylinders and oxygen cylinders.

The second compartment, the aft one, was uninhabited and was intended to accommodate the mechanisms of the main power plant and other shipboard equipment.

Initially, the mini-submarine had a combined main power plant based on a diesel engine. In the surface position, he worked on traditional diesel fuel, and in the underwater position he used two–component fuel - ordinary and hydrogen peroxide.

The main power plant used on the mini-submarine was thus a variant of the famous engine developed by the German engineer Helmut Walter. Such an engine went to the US Navy as a trophy along with the German submarine U-1406 of the Type XVIIB project. The latter was loaded on board the Shomaker transport on September 14, 1945 and sent to the USA the next day.

However, there were some differences. In the classic Walter turbine engine, concentrated hydrogen peroxide was used as an energy carrier and oxidizer, which, under the influence of various catalysts, decomposed with the release of a significant amount of heat and the formation of a vapor-gas mixture with a high content of oxygen and water vapor.

The vapor-gas mixture was then fed into the combustion chamber, where traditional liquid fuel was also supplied. A gorenje reaction took place, and the resulting gas mixture performed work in the turbine and drove the propeller. The spent gas mixture was sent to the condenser, after which the condensed water and carbon dioxide were removed overboard of the submarine.

On the X-1, not a turbine engine was installed, as on the captured submarine U-1406, but a diesel engine modified to work underwater with the use of hydrogen peroxide. In this case, after the decomposition of hydrogen peroxide, the resulting vapor-gas mixture was fed into the combustion chamber, where standard liquid fuel was also supplied. The resulting mixture was fed to the diesel intake manifold, and the water and carbon dioxide obtained as a result of exhaust gas treatment were removed overboard.

The supply of hydrogen peroxide was stored at the SMPL in a special soft tank with a capacity of 400 gallons (about 1514 liters). It was made of polyvinyl chloride and was located in the bow tip of the durable hull of the super-small.

Also, a battery and a backup electric motor powered by it were installed on the X-1. The latter was necessary in case of an accident of the main power plant. But it was also useful in many other cases, because at first the Americans could not manage to establish normal operation of the main power plant X-1.

However, the experimental power plant ultimately did not last long on a mini-submarine. This happened after the end of the test cycle, which began in February 1957 in the waters of the Portsmouth Naval Shipyard.

The fact is that on May 20, 1957, a serious accident occurred on an ultra-small submarine caused by an explosion of hydrogen peroxide reserves and led to significant destruction of the bow of the SMPL. It was only by a miracle that victims were avoided, but according to the results of the investigation, the American admirals decided to re-equip the X-1 for a new main power plant. As a result, it became traditional – diesel-electric.

Later, one of the naval officers who took part in the X-1 test program noted that "the most important conclusion made as a result of this experimental program was that a large amount of unstable hydrogen peroxide should not be allowed to concentrate on a warship in any case." It is difficult to argue with such a serious conclusion.

SHORT-LIVED OPERATIONThe US Navy used the X-1 as an experimental ship in order to study the possibility of using submarines of this class to combat underwater sabotage forces and means of a potential enemy.

First of all, with Soviet underwater saboteurs, whom the West feared like fire.

Basically, the Americans studied the ability of the SMPL to ensure effective protection of its naval bases, fleet bases and ports, as well as to solve tasks to combat group submarines and enemy mini-submarines.

The X-1 was also used to solve the tasks of combat training of personnel of sabotage and anti-sabotage units of the US Navy. Subsequently, American military specialists conducted a series of tests and research exercises that helped them more accurately identify all the positive features, as well as the shortcomings of this sample of special-purpose naval equipment.

On December 2, 1957, the X-1, which was seriously damaged after the accident mentioned above, was taken out of experimental operation by the Navy and put into repair and modernization. During the implementation of these works, in addition to the actual repair (and there was something to repair – the explosion turned almost the entire bow of the mini-submarine), work was also carried out on the modernization of the SMPL.

In particular, a diesel-electric main power plant was installed on it. And then the mini-submarine was put on long-term conservation at the fleet base in Philadelphia, Pennsylvania.

In this regard, the American admirals even had to "lease" from the British their new SMPL X53 "Sprat" (Sprat, Sprat or Sprat). It was the third mini-submarine of the "Stilbe" type (Stickleback, "Stickleback") – an improved version of the famous British XE-type SMPLS of the Second World War.

FLOATING LABORATORYHowever, already in December 1960, the X-1 was delivered to Annapolis, Maryland, where it was reintroduced to the first line and transferred to the 6th Submarine Division.

This time she was assigned to the Small Craft Facility, which was organizationally part of the Navy Command in the Severn River area (sometimes also referred to as the Severn River Naval Command).

In its "second life", the X-1 was used for experimental purposes in the Chesapeake Bay area. Here, under the direct supervision of specialists from the Naval Research Laboratory of the US Navy, she took part in a fairly large-scale test program.

Among them, it can be noted, for example, tests to determine the nature of changes in seawater in a certain area as a result of the passage of a submarine in it: pigmentation, turbidity and the coefficient of surface tension of water were evaluated, and in some experiments microbiological analysis of water samples was also performed. At the same time, the specialists of this laboratory monitored the evolutions of the mini-submarine from a special platform installed under the automobile bridge crossing the Chesapeake Bay.

Finally, the special-purpose SMPL X–1 was decommissioned by the decision of the US Navy Command on February 16, 1973, and on April 26 of the same year it was transferred to the balance of the US Navy Shipbuilding Research and Development Center in Annapolis (Naval Ship Research and Development Center - NSRDC). Well, the following year, on July 9, permission was received to include this mini-submarine as a historical exhibit in the museum exposition of this center, which was organized on the territory of the Naval Complex "North Severn" near Annapolis.

Later, X-1 once again changed the place of residence. And ultimately, the unique mini-submarine found its last resting place in the open exposition of the Museum and Library of the US Navy Submarine Forces.

This museum complex is located in Groton (Connecticut), and its main and most famous exhibit is the world's first nuclear submarine "Nautilus" (USS Nautilus; SSN-571).

The X-1 was transferred to this museum in April 2001. And since then, along with other samples of naval equipment of American and foreign origin, it has been on open display there, representing an object of constant high interest from visitors.

Vladimir Shcherbakov

Deputy Executive Editor of HBOVladimir Leonidovich Shcherbakov is a military expert.