by Marina KHALIZEVA

Academician Nikolai Khlopkin (1923-2012), whose 90th birth anniversary was marked by the scientific community at the end of 2013, is one of the outstanding persons in national atomic shipbuilding. Hero of Socialist Labor, laureate of Lenin and State prizes of the USSR, he was one of the people, who determined the modern image of marine nuclear installations. Built with his participation atomic icebreakers, submarines of four generations and surface ships put Russia in the forefront of the countries, which mastered the World Ocean potential.

EARLY YEARS OF LIFE

After he had left the secondary school with a certificate of merit in Petushki (Vladimir Region) in 1940, Khlopkin entered the Heat Power Engineering Department of the Moscow Power Engineering Institute. But his studies were interrupted by an outbreak of the war. After he had passed the first year exams, he together with other students in July of 1941 left for the Dnieper region near Smolensk to dig antitank trenches and construct weapon emplacements. He witnessed there a breakthrough of our defense in the Vyazma direction. He wrote: "We were shocked by ruthless truth of the war which was hard to compare with the prewar notions." He returned to Moscow in the hard October days by one of the last trains.

The institute was evacuated to Leninogorsk, the East Kazakhstan Region, where Khlopkin was called up for military service in February of 1942. After he had passed an accelerated course of training at the Tambov Infantry School (Semipalatinsk), he in the rank of lieutenant was sent to the Voronezh front. In battles he got wounded and spent in hospitals 14 months. But at the end of 1943, he returned to the front. In the capacity of deputy chief of staff of the rifle regiment he covered the distance from the town of Shepetovka (Zhitomir Region, Ukraine) to Berlin and left his signature on the walls of the defeated

Reichstag. He wrote later: "By this signature seen by one of my fellow students, it became known at the institute that 1 was still alive." He returned to the institute in the rank of captain with 3 war decorations.

He defended his diploma work "Working Out of a Reactor Plant for Atomic Power Station" at the famous Laboratory of Instrumentation of the USSR Academy of Sciences (today the National Research Center "Kurchatov Institute")* headed by Acad. Igor Kurchatov**. The Chairman of the State Commission Acad. Anatoly Alexandrov*** took notice of him and highly assessed the suggested project. Thereafter they worked together for 40 years. Khlopkin called Alexandrov his "great teacher". He confessed: "He exerted an exceptional influence on my personal formation as a research fellow and on all

* See: A. Gagarinsky, Ye. Yatsishina, "From a Secret Laboratory to a National Research Center", Science in Russia, No. 2, 2013.--Ed.

**See: Ye. Velikhov, "Pride of Russian Science"; V. Sidorenko, "Pioneer of Soviet Atomic Power Engineering"; Yu. Sivintsev, "A Few Unforgettable Meetings"; R. Kuznetsova, V. Popov, "Scientific Heritage of Academician Kurchatov", Science in Russia, No. 6, 2012.--Ed.

*** See: N. Ponomarev-Stepnoi, "At the Head of the Nuclear Branch", Science in Russia, No. 2, 2003; Ye. Velikhov, "Unable to Live Otherwise"; M. Mokulsky, "Rebirth of the Nation's Genetics"; V. Popov, "Scientific Works of Academician Alexandrov", Science in Russia, No. 1, 2013.-Ed.

my life. I could learn everything from him: attitude to the assigned work, striving to accomplish it, thorough studies of events paying attention even to trifles, and attitude to people."

The diploma with honors (1950) opened up new prospects to the young engineer at the Kurchatov Institute, where strategically thinking people were engaged in the formation of a new industry, i.e. atomic power engineering. Khlopkin's first steps in this profession were connected with studies of efficiency of commercial reactor fuel tanks, which he later (in 1956) summed up in his Ph. D. thesis. But soon another task advanced to the forefront.

ORIGINATION OF THE ARCTIC FLEET

In 1953, the work to create the first national atomic submarine and a ground prototype of its reactor plant was under way in the country. Both Kurchatov and Alexandrov believed that enormous funds put into creation of a power plant for the atomic submarine should be used in national economy. In other words, shell-type reactors of submarines are technologically fit to be used on ships of peaceful application. Therefore, at the end of 1953 two academicians initiated publication of a governmen-

tal decree on building of a powerful icebreaker for Arctic regions. Khlopkin recalled: "The field of application of peaceful atomic power engineering was well-chosen. It was required for Arctic regions, but Arctic regions were also necessary for atomic power engineering as its advantages over power engineering using organic fuel could become apparent here most of all."

The research assistant of the project Anatoly Alexandrov paid special attention to an atomic steam-generating plant, which had to provide increased maneuverability, stability guaranteeing sustained movement in a complex ice situation, and radiation safety. He invited the best scientific and technical staff of the country to create such power plant. At the Kurchatov Institute they were concentrated, in particular, in Sector 6 headed by Vladimir Merkin, Dr. Sc. (Tech.), former chief technologist of the first commercial reactor "A" for production of armor plutonium*. Under his command there worked a group of specialists in physics and thermophysics headed by Khlopkin, who formed technical assignment for an icebreaker nuclear plant. It was concerned with problems of reactor core physics, nuclear and radiation safety. For this purpose the specialists made physical and thermohydraulic estimates and a new lay-out of the steam-generating equipment with biological protection from ionizing radiation. Khlopkin and his colleagues coordinated the whole work with the chief designer of the reactor Igor Afrikantov, Dr. Sc. (Tech.), head of Machine-Building Plant No. 92 in the city of Gorky, where the main equipment for the power plant was produced. The work went well, and by the middle of 1955 the reactor project was approved.

*See: M. Khalizeva, "No Hit-or-Miss Chance", Science in Russia, No. 4, 2008.-Ed.

The first atomic ice ship Lenin was built on the stocks of the Naval Dock-yard in Leningrad. On December 5, 1957, it was launched, and in 1959 the project reached a closing stage. Khlopkin resolved all practical problems right away. He participated in core fuelling, startup of reactors and overall mooring trials. The work of hundreds of designers, scientists and engineers was successful, and on December 3, 1959, the government commission signed an act on the transfer of the atomicpowered vessel for experimental operation to the Murmansk Marine Steamship Company. This event went down in history as the birthday of the national atomic icebreaking fleet.

Khlopkin wrote later: "The icebreaker Lenin opened up a new era of peaceful use of atomic power engineering on the sea. It managed to break not only Arctic ice but also neutralized opposition of bureaucrats and skeptical scientists who used to say that we were building an icebreaker which would not sail." But during the first six years the giant atomic icebreaker covered above 82,000 sea miles and piloted independently more than 400 vessels, showing excellent efficiency. It is difficult to overestimate its role in the development of the Northern Sea Route as the atomic icebreaker scaled up navigation time 2-fold (from 3.5 to 7 months), increased the rate and safety of leading convoys of vessels, opened new routes and cargo delivery methods. Khlopkin summed up the accumulated material on creation of the icebreaker reactor plant in his doctoral thesis (1968).

NEW IMAGE OF THE ATOMIC SUBMARINE

In 1962, Khlopkin was appointed deputy head for marine nuclear power plants by Alexandrov and found himself in the center of events connected with creation of the second and third generations of submarines with water-cooled pressurized reactors*. The main goal was to the increase service life of pipe systems of steam generators for atomic submarines and energy resources of reactor cores. The expansion of the range of works called for creation of physical and engineering laboratories. They were incorporated in Sector 67 headed by Khlopkin from 1966. He was appointed deputy head of the department for transport units in 1968, and became department head in 1970. In those years his scientific interests were focused mainly on perfection of submarine reactor cores. Above 15 types and varieties of such units were tested under his guidance.

He participated in mooring trials of head submarines of the second and third generations. The complex group of the Kurchatov Institute used specially made recording instruments to identify all defects and provide recommendations to eliminate them. But the main tactical and technical characteristics used in the improved projects such as speed, maneuverability and ultimate depth of submersion were, as a rule, verified, as they were essential properties of submarines. High speed afforded more opportunities to avoid torpedoes and disengage

*See: M. Gladkov, "A-Fleet Pioneers", Science in Russia, No. 3, 1999.--Ed.

from the enemy. Khlopkin noted: "Our atomic submarines surpassed American counterparts in these characteristics from the very beginning. As concerns the speed parameters of submarines of Project No. 661 (44.7 knots = 83 km/h) and Project No. 705 (42 knots = 78 km/h) they are record figures up to now and have not been surpassed by foreign submarines."

In Khlopkin's opinion it was difficult to solve the problem of reticence of the submarine, mainly, noisiness. Its urgency increased due to the appearance of long-range and high-precision weapons. It turned out to be more difficult to provide latent actions of submarines with such "filler" than to create a new reactor plant. But this problem was also eliminated due to reduction of acoustic radiation, which was taken into consideration in the comprehensive design of atomic submarines. The submarines of a new generation became peculiar acoustic "black holes" in the sea which cannot be located and classified.

PROJECT 1144

The portrait of Khlopkin would have been incomplete if we do not mention his participation in creation of reactors for heavy atomic cruisers. Combat vessels of big displacement (800 t) equipped with atomic power plants which can operate in remote regions of the World Ocean as a part of grouping or independently, chiefly with antisubmarine tasks, became an objective need of the national navy in the mid-1960s. The scientists got a tactical and technical assignment for their development (Project 1144) in 1969. In 1972, the design phase was completed, and in the spring of the following year the keel-laying of a vessel took place at the Baltiysky Shipbuilding Yard. The vessel was called Kirov (from 1992 Admiral Ushakov) in honor of the legendary light artillery cruiser of Project 26 removed from the Navy Combat make-up.

Khlopkin, who took part in the elaboration of a nuclear power plant for the carrier rocket, recalled that his atomic steam-generating plant became a "headache" problem. The point is that a two-reactor design used for the first Soviet atomic submarines no longer met the capacity requirements, while a three-reactor design for the icebreaker Lenin was too big for the surface vessel due to its dimensions and mass, and did not suit the military for other reasons as well. It was necessary to design a new atomic set for the Kirov and develop a concept of safety including systems of emergency cooling of the reactor and accident localization. The developers used a block layout system, which allowed to decrease the power plant dimensions and improve its operating parameters.

The head ship was launched at the end of 1977 and then for over two years was being finished afloat. Khlopkin and his colleagues participated in mooring trials of the antisubmarine cruiser, which was transfered to the Northern Navy in 1980.

After Acad. Alexandrov left his post as director of the Kurchatov Institute of Atomic Energy in 1987, Khlopkin carried out scientific supervision of national marine nuclear plants used for military and civil purposes.

ON THE NORTH POLE

For many years mankind strived to conquer the North Pole. For the first time in history the expedition of the American traveler Robert Peary reached it in 1909. In 1937 the Soviet drifting station "North Pole 1" was set up there. It was headed by the famous researcher Ivan Papanin. Thereafter, over the point of intersection of the rotation axis of the Earth, there were flying airships and aircraft, sleigh expeditions were taking place and submarines were rising to the surface, but not a single surface vessel capable of free floating in the polar ice visited this intriguing place. In 1975 such opportunity appeared when the second atomic vessel Arktika came into operation in our country. It was more powerful (75,000 h.p.) than the first such vessel and possessed good technical characteristics and an excellent icebreaking potential. It was just this atomic giant headed by the captain Yuri Kuchiev that was honored to undertake this first in the world unprecedented sea voyage. Khlopkin was among 200 and a bit more lucky men who started on August 9, 1977, from Murmansk to the Earth's top.

He recalled: "It was a fascinating sight to watch the icebreaker, especially when we passed through hummocks. The summer midnight sun had already thawed the upper part of ice. Sometimes cracks in ice piles reached 10-15 m under water. When meeting such a hummock, the icebreaker drops its speed, its head starts going up and then suddenly collapses. Thunder, crash

and fountains of splashes going up to dozens of meters... Blows of the hull against uneven edges of ice-floes and side throws of the icebreaker completely disagree with its huge mass. You grab convulsively at handrails or anything else at hand. "Thunder claps" when ice-floes break sound like a gunshot. The critical strain of mechanisms causing the hull vibration." On August 17, 1977, at 4 a.m., struggling through an unthinkable depth of ice the Arktika reached the point in question. This took less than eight days and three of them from the edge of ice-free water. "A fantastic result," said Khlopkin later.

The expedition members marked this event with a ceremony of raising a USSR state flag on a 10 m steel mast installed on the ice. The atomic-powered vessel stayed on the Earth's top for 15 hours. During this time the scientists carried out a set of important studies and observations and, before leaving they hauled down a memorial metal plate with an image of the USSR state emblem into the waters of the Arctic Ocean. Later Khlopkin wrote in the institute's newspaper The Soviet Physicist: "The sea voyage to the North Pole clearly demonstrated that we can reach any region of the Arctic basin. The voyage confirmed the great interest of the state in the Northern Sea Route as our main national traffic artery. Therefore, it is not accidental that T. Guzhenko, Minister of the USSR Navy, was appointed head of the trip."

THE LIGHTER-ENGINE SEVMORPVT

Later the following icebreakers built at the Baltiysky Shipbuilding Yard were put into operation (1971-1992): Sibir, Rossiya, Sovetsky Soyuz and Yamal* of 75,000 h.p. capacity each. Built in cooperation with the Finnish partners two giant ships Taimyr and Vaigach of shallow draught but sufficient capacity of 50,000 h.p. operated in the estuaries of the Siberian rivers, which linear atomic-powered vessels could not enter because of a shallow depth.

Successful operation of such representative icebreaker fleet called for respective transport vessels. The atomic lighter-aboard ship Sevmorput was the first cargo ship capable of moving independently in ice up to 1 m thick. It had 62,000 t displacement and was launched from the berth of the Zaliv Shipbuilding Yard (Kerch, Ukraine) in 1986 and put into operation in 1988. Khlopkin was supervisor of studies of this project. Most of the time Sevmorput operated on the route Dudinka--Murmansk (from 2007 it is at the berth of the Murmansk Steamship Company waiting for further employment).

OFFSHORE NUCLEAR POWER PLANTS

Khlopkin always linked the prospects of civil marine nuclear power engineering with the development of offshore nuclear power plants**. Attempts to create a self-contained power unit were made since 1999. But only in 2005 after long assessments and expert examinations the board of the Federal Nuclear Energy Agency approved the project of the first offshore nuclear power plant with

*See: A. Chechurov, "Champion Among Atomic Giants", Science in Russia, No. 3, 2009; V. Makarov, "The Future of Marine Nuclear Power", Science in Russia, No. 4, 2010.--Ed.

**See: M. Khalizeva, " Electricity and Heat: Delivery to the Consumer", Science in Russia?, No. 4, 2013.--Ed.

the symbolic name "Academician Lomonosov". The Petersburg Company "Baltiysky Zavod--Shipbuilding" undertook implementation of the project and promised to deliver the vessel to the customer in 2016. Khlopkin strained every effort for realization of a new class of reactors in this project.

The mobile electric power station with an autonomous plant KLT-40S, created on the basis of a serial icebreaker unit and tested during a long operation in the Arctic regions has electric capacity of 70 MW. Meant in the best way for operation in difficult of access regions, far from centralized power supply systems, it can provide power to big industrial enterprises, ports and offshore oil-and-gas extracting and processing complexes.

However, even this project, which used previous experience to the fullest, could not do without innovations. For example, the developers reduced the neutron effect on the reactor shell material, which allowed to prolong the service life of the plant key element to 40 years. The channel structure of the reactor core used in icebreakers was replaced by a cassette design, which increased the specific uranium fuelling by 15 percent. The fuel element composition was changed to the so-called "cermet" fuel (microparticles of uranium dioxide in zirconium matrix), which increased uranium capacity by 2.5 times while keeping other high parameters of fuel loading. According to the plans of the Rosatom State Corporation, financing the project, the first autonomous power plant will be delivered to the town of Pevek in the Far East.

In the course of celebrations of Khlopkin's 80th birth anniversary his colleagues recalled: "Meeting Khlopkin only in work environment it is hard to believe that he is a venturesome and passionate person: mountaineering, canoeing on rivers, lakes and even seas, fishing and photography. And how he enjoys mushrooming! In his home village of Ilyinka he knows what mushroom grows under what tree or bush. When he goes to a forest to pick berries, you can be sure that he will bring at least a bucket of them... Nikolai Sidorovich is fond of fishing but only on leave. And the whole party is sure to get a perfect fish diet. This is his way of life--life to the fullest. Besides, the echoes of his marine activities were felt all the time. His friends called him "admiral", and seamen-- "favourite Academician of the Navy". When these words were pronounced in public by one of the naval officers on the day of the 80th birth anniversary of Khlopkin, the latter could not conceal his emotions. After all, it was in fact the greatest recognition of a real scale of his activities.