Post WWII Soviet Cruisers

Posted on February 28 2010 at 05:34 AM

Project 70E modified Sverdlov class cruiser Dzerzhinsky in the Mediterranean on 3 April 1970. Completed in 1952 as a light cruiser (Project 68bis), she was rebuilt with in the early 1960's with an M-2 Volkhov SAM system (NATO SA-N-2 'Guideline') replacing her aft turrets. She was an active unit of the Black Sea Fleet until her 1987 decommissioning, frequently deploying to the Mediterranean.

SOVIET UNION: SVERDLOV-CLASS


Units: Sverdlov, Zhdanov, Admiral Lazarev, Admiral Ushakov, Admiral Senyavin, Dmitry Pozharski, Varyag, Ordzhonikidze, Aleksandr Nevski, Aleksander Suvarov, Oktyabrskaya Revolutsiya, Murmansk,

Dzerzhinski, Admiral Nakhimov, Mikhail Kutuzov

Type and Significance: These light cruisers were among the world’s last vessels whose armament was composed solely of guns.

Dates of Construction: Laid down between 1949 and 1954, with the last being completed in 1955.

Hull Dimensions: 689’ x 72’ 2” x 24’ 7”

Displacement: 16,000 tons

Armor: A belt with a maximum thickness of 5 inches, a deck that varied between 3 inches and 1 inch in depth, and 5-inch turret armor.

Armament: 12 5.9-inch guns in four triple gunned turrets, two each being located fore and aft, 12 3.9-inch guns, antiaircraft weapons, and 10 20.8-inch torpedo tubes.

Machinery: Turbines fed by six oil-fired boilers that could produce 110,000 horsepower.

Speed: 32.5 knots

Complement: 1,010

These ships engendered alarm in the naval officials of the Western powers, as they were perceived as significant threats. Although powerful in appearance, however, the Sverdlov-class cruisers were rendered largely obsolete by the beginning of the missile age. The Admiral Nakhimov and Dzerzhinski were refitted in the late 1950s to test early Soviet SSM batteries. The former unit was scrapped in 1961. The Ordzhonikidze was sold to Indonesia the following year and sold for scrap in 1972. All the other units except one were scrapped by 1994. The Mikhail Kutuzov was put in reserve in 1989 and remains in that status.

The Soviet Union led the way in the development of new cruisers. In 1950, Stalin, despite enduring economic problems, instituted a 10-year construction program that included 40 cruisers, being a collection of battle cruisers, heavy cruisers, and light cruisers. His goal was the restoration of the navy, after it had largely languished during the war, in order to match the naval strength of the Western powers. Construction on the first units was already under way as Stalin initiated the plan. These were the 14 light cruisers of the Sverdlov class. Production of these imposing vessels began in 1949; the final ship was not ready for sea until 1955. The Sverdlov-class light cruisers measured 689 feet by 72 feet, 2 inches, displaced 16,000 tons, and were protected by a combination of light belt and deck armor. Their primary armament consisted of 12 5.98-inch guns in four triplegunned turrets, two each located fore and aft. They also mounted smaller secondary guns and lighter antiaircraft weapons. These batteries benefited from radar equipment for calculating ranges to targets. Their engines could produce a maximum 32.5 knots. Between 1951 and 1952, work on further ships in the plan began when the keels of the two battle cruisers of the Stalingrad-class were laid down. The design called for vessels that measured 836 feet, 8 inches by 103 feet and displaced 40,000 tons. Their primary armament was projected as six 12-inch guns.

As production on the Stalingrad-class battle cruisers commenced, the first of the Sverdlov-class light cruisers were appearing on the world’s oceans. They made a deep impression on naval officials in the United States and Western Europe, who viewed them as a significant threat. The United States responded with the last cruisers whose construction had commenced during the war. Great Britain, owing to economic difficulties that plagued the other Western powers, was the only U.S. ally that built cruisers at the same time as the Soviet ships. These were the three light cruisers of the Tiger-class. Like the U.S. vessels, these ships were based on a wartime design. Owing to economic problems and the need to redesign them for newer detection systems, the first unit was not ready for service until 1959.

The continued justification for gun cruisers, however, was negated by further technological innovation in the Soviet Union between 1962 and 1969 that challenged the U.S. lead in guided missile cruiser design. Following World War II, Stalin had concentrated on constructing a navy that could defend the coasts of the Soviet Union and a few large vessels that could project power further overseas. These larger vessels were armed solely with guns. Upon Stalin’s death in 1953, successor Nikita Khrushchev shifted the priorities of the Soviet surface navy toward the incorporation of missiles. He recognized that the advent of the missile cruiser would ultimately lead to the gun cruiser’s obsolescence. Indeed, he believed that the sole priority of the Soviet Union should be the production of nuclear missile technology. A reflection of Khrushchev’s beliefs was the decision to end construction of the Stalingrad-class battle cruisers. He also characterized the units of the Sverdlov-class, although production continued, as “floating coffins.” New cruiser designs were subsequently drawn up under the direction of Sergei Gorshkov, commander in chief of the navy since 1956, and relied on the Soviet missile program for their armament.

The Soviet program, like that of the United States, had begun in earnest in the months following the end of World War II with the acquisition of German rocket technology. Soviet experiments with German equipment eventually produced missiles in the mid–1950s that alarmed Western powers; increasingly the Soviet Navy posed a greater strategic threat through missile deployment. In September 1955, the Soviet Union became the first nation to fire a submarine launched ballistic missile (SLBM), a weapon that could carry a nuclear warhead and deliver it to a target hundreds of miles away. The Soviets also produced the first conventionally powered ballistic missile submarine in 1958. At the same time, the Soviets were in the process of developing missile systems for surface ships. In the late 1950s, the Sverdlov-class cruiser Dzerzhinski was refitted to test the first-generation Soviet SAM batteries.

Experiments were also under way for the world’s first surface-to-surface missile (SSM) for use against other vessels. This latter type was the result of the need for an offensive capability against NATO aircraft carriers owing to the fact that the Soviet Union had no seabased airpower. Soviet officials viewed Western aircraft carriers as a threat to the Soviet Union itself, as they could launch aircraft armed with nuclear weapons against Soviet military sites and cities. Another Sverdlov-class cruiser, Admiral Nakhimov, was refitted to test the first of the SSM systems, SS-N–1, in the late 1950s.

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The Changing Technology of Naval Battles

Posted on January 08 2010 at 06:39 AM

Jin and Sung dynasty warships.

In the days of the galley, battle was a complex affair that mixed the techniques of land and sea warfare. Thus a contemporary report of the battle between Demetrius and Ptolemy in 306 BC off Salamis:

The two fleets being then about 600 yards apart, Demetrius gave the signal to engage by hoisting a golden shield which was seen by all [and doubtless repeated by light craft in rear of the line]. Ptolemy did the same and the two fleets closed quickly with each other, as the trumpets sounded the charge and the crews cheered. The engagement opened with archery and stones and darts from the catapults, and many were wounded during the approach. The contact was made, the rowers being incited by the boatswains to make their greatest exertions, and the men on deck fell on the enemy with spears. The first shock was violent, some ships had their oars swept from their sides and remained motionless with their soldiers out of action. Others, after striking, rowed astern to ram again and in the meantime the soldiers attacked each other hand to hand. Some captains struck their opponents broadside to broadside, and the ships being held in contact became so many fields of battle with the boarders leaping to the enemy’s deck. In some cases these missed their footing and falling overboard were drowned, while others making good their foothold killed the enemy or drove them overboard. Many and varied were the fortunes of the ships. In one case a weaker crew was victorious owing to its higher deck and in another case the better crew lost because its decks were low. For luck has much to do in naval actions. On shore valour is pre-eminent, whereas at sea many accidents occur which bring ruin to those whose valour deserves success.

The Chinese also developed technologies that turned battle more into stand-off affairs, although ramming and close action still usually marked their closing stages. In AD 1161 the large navy of the Song dynasty destroyed an invading Jin armada in two battles in coastal waters and on the Yangtse River at the Chenjia peninsula and Caishi respectively. These battles were won by armoured warships (some equipped with paddlewheels) equipped with stand-off weaponry including fire arrows and bombs and explosives fast-fired from trebuchets on deck. There is no doubt that these two battles were decisive for the future of Song China.

In the Indian Ocean of the late fifteenth century, the Portuguese took this one stage further with the marine nail and naval artillery. The result was a series of technology-determined encounters in which small Portuguese squadrons smashed much more numerous fleets and dominated the area for decades. The next stage in the development of naval battle was marked by the attention paid to securing the levels of physical control required to wield the battlefleet as a cohesive whole in order to make the most of the naval artillery that it could provide. As the British discovered, this could, however, lead to a reliance on the sanctity of the line that often stifled tactical initiative and limited battle outcomes.

At the end of the eighteenth century, a Nelsonian stress on ‘mission command’ in which responsibility for making tactical decisions in the light of the commander’s intent was delegated downwards, restored the situation and helped to produce more such decisive encounters as the battles of the Nile and Trafalgar. Nelson conceived an Admiral’s task to be ‘to bring an enemy’s fleet to battle on the most advantageous terms to himself’. No further order should be necessary, ‘Being assured that the admirals and captains of the fleet that I have the honour to command will, knowing my precise object, that of a close and decisive battle, supply any deficiency in my not making signals.’ The problem was that Nelson’s brilliant success produced a set of expectations for future battles that proved impossible for his successors to realise.

Naval technology advanced only incrementally during most of the sailing ship era, but in the nineteenth and twentieth centuries, the world’s navies were engulfed in a rising flood of new technology. Propulsion, weaponry and protection were all revolutionised, and there were many who supposed that the principles of maritime strategy and concepts of battle would change too.

Some believed that the sureness and independence of movement that steam power afforded allowed the science of evolutions to be exact and geometric, making possible pretty manoeuvres in triangles, squares and parallel lines. Others thought steam would plunge the naval battle immediately into a ferocious and swirling confusion. Views were equally divided about the ram (the idea of which fleetingly and perversely reappeared after the Battle of Lissa in 1866), the breech-loading gun, the torpedo, the mine, the submarine and, eventually, the aircraft. These developments had a profound influence on the philosophy of ship design: they revolutionised the size and shape of the fleet, completely altering the way in which ships were classified and organised. Instead of the traditional threefold division of ships-of-the-line, cruisers and frigates, there grew up an endless variety of specialised ships and also the almost metaphysical notion of ‘the balanced fleet’ – a formation in which all the diversity of modern naval warfare was adequately represented and efficiently coordinated. These technological developments transformed the tactics of battle, and therefore the form and style of naval operations and strategy.

This process gathered momentum through the twentieth century. As that century closed, there were many who thought, and who continue to think, that the arrival of a new information age will have equally far-reaching consequences of every aspect of naval activity in the twenty-first century. Even so, access to and use of the latest naval technology is only one of the determinants of the nature and consequence of naval operations.

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Ship gun fire-control systems

Posted on December 08 2009 at 06:23 AM

Ship gun fire-control systems (GFCS) enable remote and automatic targeting of guns against ships, aircraft, and shore targets, with or without the aid of radar or optical sighting. Most US ships destroyers or larger (but not destroyer escorts or escort carriers) employed GFCS for 5 inch and larger guns, up to battleships such as the USS Iowa. After the 1950s, GCFSs were integrated with missile fire-control systems and other ship sensors.

The major components of a GFCS are a manned director, with or replaced by radar or television camera, a computer, stabilizing device or gyro, and equipment in a plotting room [1] The brains were first provided by the Mark 1A Fire Control Computer which was an electro-mechanical analog ballistic computer that provided quick and accurate near real-time first-shot hit firing solutions which could automatically control one or more gun mounts against stationary, or moving targets on the surface or in the air. This gave American forces a technological advantage in WWII against the Japanese who did not develop this technology, and still used visual correction of shots with colored splashes. Digital computers would not be adopted for this purpose by the US until the mid 1970s. However, it must be emphasized that all analogue AA fire control systems had severe limitations, and even the USN Mk 37 required nearly 1000 rounds of 5" mechanical fuze ammunition per kill, even in late 1944. [2]

Mk 37 Director c1944 with Mk 12 (rectangular antenna) and Mk 22 "orange peel"

The MK 37 was the first of a series of evolutionary improvements in gun fire control systems.

1. History

Naval fire control is more complex than for single ground-based gun because of the need to control the firing of several guns at once. In naval engagements both the firing guns and target are moving, and the variables are compounded by the greater distances and times involved. Furthermore, a ship rolls and pitches, making gyroscopic stabilization extremely desirable. Naval gun fire control potentially involves three levels of complexity. Local control originated with primitive gun installations aimed by the individual gun crews.

The director system of fire control was pioneered by British navy in 1912. All guns were laid from a central position placed above the bridge as high as possible. The director became a design feature of battleships, with Japanese pagoda-style masts designed to maximize the view of the director over long ranges. A fire control officer who ranged the salvos transmitted elevations and angles to individual guns. Coordinated gunfire from a formation of ships at a single target was a focus of battleship fleet operations. Corrections are made for surface wind velocity, firing ship roll and pitch, powder magazine temperature, drift of rifled projectiles, individual gun bore diameter adjusted for shot-to-shot enlargement, and rate of change of range with additional modifications to the firing solution based upon the observation of preceding shots.

Rudimentary naval fire control systems were first developed around the time of World War I. For a description of one, see US Naval Fire Control, 1918.

For the UK, their first system was built before the Great War. At the heart was an analogue computer designed by Commander (later Admiral Sir) Frederic Charles Dreyer that calculated rate of change of range. The Dreyer Table was to be improved and served into the interwar period at which point it was superseded in new and reconstructed ships by the Admiralty Fire Control Table. [3]

The use of Director controlled firing together with the fire control computer moved the control of the gun laying from the individual turrets to a central position, although individual gun mounts and multi-gun turrets may retain a local control option for use when battle damage limits Director information transfer. Guns could then be fired in planned salvos, with each gun giving a slightly different trajectory. Dispersion of shot caused by differences in individual guns, individual projectiles, powder ignition sequences, and transient distortion of ship structure was undesirably large at typical naval engagement ranges. Directors high on the superstructure had a better view of the enemy than a turret mounted sight, and the crew operating it were distant from the sound and shock of the guns.

Unmeasured and uncontrollable ballistic factors like high altitude temperature, humidity, barometric pressure, wind direction and velocity required final adjustment through observation of fall of shot. Visual range measurement (of both target and shell splashes) was difficult prior to availability of RADAR. The British favoured coincident rangefinders while the Germans and the U.S. Navy, stereoscopic type. The former were less able to range on an indistinct target but easier on the operator over a long period of use, the latter the reverse.

In a typical WWII British ship the fire control system connected the individual gun turrets to the director tower (where the sighting instruments were) and the analogue computer in the heart of the ship. In the director tower, operators trained their telescopes on the target; one telescope measured elevation and the other bearing. Rangefinder telescopes on a separate mounting measured the distance to the target. These measurements were converted by the Fire Control Table into bearings and elevations for the guns to fire on. In the turrets, the gunlayers adjusted the elevation of their guns to match an indicator which was the elevation transmitted from the Fire Control table - a turret layer did the same for bearing. When the guns were on target they were centrally fired. [4]

In the Battle of Jutland, while the British were thought by some to have the finest fire control system in the world at that time, during the Battle of Jutland only 3% of their shots actually struck their targets. At that time, the British primarily used a manual fire control system. The one British ship in the battle that had a mechanical fire control system turned in the best shooting results. [5] This experience contributed to computing rangekeepers becoming standard issue. [6]

The US Navy's first deployment of a rangekeeper was on the USS Texas (BB-35) in 1916. Because of the limitations of the technology at that time, the initial rangekeepers were crude. For example, during World War I the rangekeepers would generate the necessary angles automatically but sailors had to manually follow the directions of the rangekeepers. This task was called "pointer following" but the crews tended to make inadvertent errors when they became fatigued during extended battles. [7] During World War II, servomechanisms (called "power drives" in the U.S. Navy) were developed that allowed the guns to automatically steer to the rangekeeper's commands with no manual intervention, though pointers still worked even if automatic control was lost. The Mk. 1 and Mk. 1A computers contained approx. 20 servomechanisms, mostly position servos, to minimize torque load on the computing mechanisms. [8]

During their long service life, rangekeepers were updated often as technology advanced and by World War II they were a critical part of an integrated fire control system. The incorporation of radar into the fire control system early in World War II provided ships the ability to conduct effective gunfire operations at long range in poor weather and at night. [9]

The Aichi Clock Company first produced the Type 92 Shagekiban Low Angle analog computer in 1932. The USN Rangekeeper and the Mark 38 GFCS had an edge over Imperial Japanese Navy systems in operability and flexibility. The US system allowing the plotting room team to quickly identify target motion changes and apply appropriate corrections. The newer Japanese systems such as the Type 98 Hoiban and Shagekiban on the YAMATO class were more up to date, which eliminated the Sokutekiban, but it still relied on 7 operators. In contrast to US radar aided system, the Japanese relied on averaging optical range finders, lacked gyros to sense the horizon, and required manual handling of follow-ups on the Sokutekiban, Shagekiban, Hoiban as well as guns themselves.

This could have played a role in Center Force’s battleships dismal performance in the Battle off Samar in October 1944. [10] In that action, destroyers pitted against the world's largest armored battleships and cruisers dodged shells to within torpedo firing range, while lobbing hundreds of accurate automatically-aimed 5 inch rounds on target. Cruisers did not land hits on splash-chasing escort carriers until after an hour of pursuit to close within 5 miles. Although the Japanese pursued a doctrine of achieving superiority at long gun ranges, one cruiser fell victim to secondary explosions caused by hits from within the range of carrier-based single "peashooter" 5 in guns. Eventually with the aid of hundreds of carrier based aircraft, a battered center force was turned back just before it could have finished off survivors of the lightly armed task force of screening escorts and escort carriers of Taffy 3. The Battle of the Surigao Strait also established the clear superiority of US radar-assisted systems at night.

The rangekeeper's target position prediction characteristics could be used to defeat the rangekeeper. For example, many captains under long range gun attack would make violent maneuvers to "chase salvos." A ship that is chasing salvos is maneuvering to the position of the last salvo splashes. Because the rangekeepers are constantly predicting new positions for the target, it is unlikely that subsequent salvos will strike the position of the previous salvo. [11] Practical rangekeepers had to assume that targets were moving in a straight-line path at a constant speed, to keep complexity to acceptable limits. A sonar rangekeeper was built to include a target circling at a constant radius of turn, but that function had been disabled.

Only the US achieved 'blindfire' radar fire-control, with no need to visually acquire the opposing vessel. The Axis powers all lacked this capability. Classes such as Iowa and South Dakota could lob shells over visual horizon, in darkness, through smoke or weather. American systems had the best stable vertical elements, so they could keep a solution on a target even during maneuvers. U.S. battleships could both shoot and maneuver, whereas their opponents could only do one or the other. [12] (In today's terminology, stable elements or stable verticals would be called vertical gyros.)

The last combat action for the analog rangekeepers, at least for the US Navy, was in the 1991 Persian Gulf War [13] when the rangekeepers on the Iowa-class battleships directed their last rounds in combat.

2. US Navy Systems

2. 1. MK 33 Gun Fire Control System (GFCS)

The Mk 33 GFCS was a power-driven fire control director, less advanced than the MK 37. It could compute firing solutions for targets moving at up to 320 knots, or 400 knots in a dive. Its installations started in 1941 on aircraft carriers with two Mk 33 directors mounted fore and aft of the island. They had no fire-control radar initially, and were aimed only by sight. After 1942, the directors were equipped with the Mk 4 fire-control radar. With the Mk 4 large aircraft at up to 40,000 yards could be targeted. It had less range against low-flying aircraft, and large surface ships had to be within 30,000 yards. With radar, targets could be seen and hit accurately at night, and through weather. [14] The Mark 33 and 37 systems used tachymetric target motion prediction. [15]

2. 2. MK 37 Gun Fire Control System (GFCS)

Development of the Sperry Mk 1 computer was begun in 1932 as part of the Mk 37 fire control system for the 5"/38 DP mount. The Royal Navy had conducted sea trials of their initial version of the High Angle Control System for AA fire, about two years earlier, in January 1930. The computer was completed as the Ford Mk 1 computer by 1935. Rate information for height changes enabled complete solution for aircraft targets moving over 400 mph. Destroyers starting with the Sims class employed one of these computers, battleships up to four. The system's effectiveness against aircraft diminished as planes became faster, but toward the end of World War II upgrades were made to the Mk37 System, and it was made compatible with the development of the VT (Variable Time) proximity fuze which exploded when it was near a target, rather than by timer or altitude, greatly increasing probability any one shell would destroy a target.

2. 2. 1. Mark 37 Director

Mk 37 Director above bridge of destroyer USS Cassin Young (DD-793) with SPG 25 radar antenna

The function of the Mark 37 Director, which resembles a turret with "ears" rather than guns, was to track the present position of the target in bearing, elevation, and range. To do this, it had optical sights (the rectangular windows or hatches on the front), an optical rangefinder (the tubes or ears sticking out each side), and later models, fire control radar antennas. The rectangular antenna is for the Mark 12 FC radar, and the parabolic antenna on the left ("orange peel") is for the Mk 22 FC radar. They were part of an upgrade to improve tracking of aircraft. [1]

The Director Officer also had a slew sight used to quickly point the director towards a new target. [16] Up to four Mark 37 Gun Fire Control Systems were installed on on battleships. On a battleship, the director is protected by 1.5 inches of armor, and weighs 21 tons. The Mark 37 director aboard the USS Joseph P. Kennedy, Jr. is protected with one-half inch of armor plate and weighs 16 tons. [17]

5 in gun on the Fletcher-class destroyer USS David W. Taylor (DD-551)

Stabilizing signals from the Stable Element kept the optical sight telescopes, rangefinder, and radar antenna free from the effects of deck tilt. The signal that kept the rangefinder's axis horizontal was called "crosslevel"; elevation stabilization was called simply "level". Although the stable element was below decks in Plot, next to the Mk.1/1A computer, its internal gimbals followed director motion in bearing and elevation so that it provided level and crosslevel data directly. To do so, accurately, when the fire control system was initially installed, a surveyor, working in several stages, transferred the position of the gun director into Plot so the stable element's own internal mechanism was properly aligned to the director.

Although the rangefinder had significant mass and inertia, the crosslevel servo normally was only lightly loaded, because the rangefinder's own inertia kept it essentially horizontal; the servo's task was usually simply to ensure that the rangefinder and sight telescopes remained horizontal.

Mk. 37 director train (bearing) and elevation drives were by D.C. motors fed from Amplidyne rotary power-amplifying generators. Although the train Amplidyne was rated at several kW maximum output, its input signal came from a pair of 6L6 audio beam tetrode vacuum tubes (valves, in the U.K.).

2. 2. 2. Plotting Room

In battleships, the Secondary Battery Plotting Rooms were down below the waterline and inside the armor belt. They contained four complete sets of the fire control equipment needed to aim and shoot at four targets. Each set included a Mark 1A computer, a Mark 6 Stable Element, FC Radar controls and displays, Parallax correctors, a switchboard, and people to operate it all.

(In the early 20th century, successive range and/or bearing readings were probably plotted either by hand or by the fire control devices (or both). Humans were very good data filters, able to plot a useful trend line given somewhat-inconsistent readings. As well, the Mark 8 Rangekeeper included a plotter. The distinctive name for the fire-control equipment room took root, and persisted even when there were no plotters.)

2. 2. 3. Ford Mark 1A Fire Control Computer

Mark 1A Computer

The Mark 1A Fire Control Computer was an electro-mechanical analog ballistic computer. Originally designated the Mark 1, design modifications were extensive enough to change it to "Mk. 1A". Sailors would stand around a box 62 inches long, 38 inches wide, and 45 inches high. Even though built with extensive use of an aluminum alloy framework (including thick internal mechanism support plates) and computing mechanisms mostly made of aluminum alloy, it weighed as much as a car, about 3125 lb, with the Star Shell Computer Mark 1 adding another 215 lb. It used 115 volts AC, 60 Hz, single phase, and typically a few amperes or even less. Under worst-case fault conditions, its synchros apparently could draw as much as 140 amperes, or 15,000 watts (about the same as 3 houses while using ovens). Unfortunately, that figure has remained in current references without explanatory qualification. (For a computer that size to dissipate 15 kW with no cooling provisions is absurd.) Almost all of the computer's inputs and outputs were by synchro torque transmitters and receivers.

Its function was to automatically aim the guns so that a fired projectile would collide with the target. [1] This is the same function as the main battery’s Mk 8 Rangekeeper above except that some of the targets the Mark 1A had to deal with also moved in elevation — and much faster. For a surface target, the Secondary Battery’s Fire Control problem is the same as the Main Battery’s with the same type inputs and outputs. The major difference between the two computers is their ballistics calculations. The amount of gun elevation needed to project a 5-in shell nine nautical miles (17 km) is very different from the elevation needed to project a 16-in shell the same distance.

In operation, this computer received target range, bearing, and elevation from the gun director. As long as the director was on target, clutches in the computer were closed, and movement of the gun director (along with changes in range) made the computer converge its internal values of target motion to values matching those of the target. While converging, the computer fed aided-tracking ("generated") range, bearing, and elevation to the gun director. If the target remained on a straight-line course at a constant speed (and in the case of aircraft, constant rate of change of altitude ("rate of climb"), the predictions became accurate and, with further computation, gave correct values for the gun lead angles and fuze setting.

Concisely, the target's movement was a vector, and if that didn't change, the generated range, bearing, and elevation were accurate for up to 30 seconds. Once the target's motion vector became stable, the computer operators told the gun director officer ("Solution Plot!"), who usually gave the command to commence firing. Unfortunately, this process of inferring the target motion vector required a few seconds, typically, which might take too long.

The process of determining the target's motion vector was done primarily with an accurate constant-speed motor, disk-ball-roller integrators, nonlinear cams, mechanical resolvers, and differentials. Four special coordinate converters, each with a mechanism in part like that of a traditional computer mouse, converted the received corrections into target motion vector values. The Mk. 1 computer attempted to do the coordinate conversion (in part) with a rectangular-to polar converter, but that didn't work as well as desired (sometimes trying to make target speed negative!). Part of the design changes that defined the Mk. 1A were a re-thinking of how to best use these special coordinate converters; the coordinate converter ("vector solver") was eliminated.

The Stable Element, which in contemporary terminology would be called a vertical gyro, stabilized the sights in the director, and provided data to compute stabilizing corrections to the gun orders. Gun lead angles meant that gun-stabilizing commands differed from those needed to keep the director's sights stable. Ideal computation of gun stabilizing angles required an impractical number of terms in the mathematical expression, so the computation was approximate.

To compute lead angles and time fuze setting, the target motion vector's components as well as its range and altitude, wind direction and speed, and own ship's motion combined to predict the target's location when the shell reached it. This computation was done primarily with mechanical resolvers ("component solvers"), multipliers, and differentials, but also with one of four three-dimensional cams.

Based on the predictions, the other three of the three-dimensional cams provided data on ballistics of the gun and ammunition that the computer was designed for; it could not be used for a different size or type of gun except by rebuilding that could take weeks.

Servos in the computer boosted torque accurately to minimize loading on the outputs of computing mechanisms, thereby reducing errors, and also positioned the large synchros that transmitted gun orders (bearing and elevation, sight lead angles, and time fuze setting).These were electromechanical "bang-bang", yet had excellent performance.

The anti-aircraft fire control problem was more complicated because it had the additional requirement of tracking the target in elevation and making target predictions in three dimensions. The outputs of the Mk 1A were the same (gun bearing and elevation), except fuze time was added. The fuze time was needed because the ideal of directly hitting the fast moving aircraft with the projectile was impractical. With fuze time set into the shell, it was hoped that it would explode near enough to the target to destroy it with the shock wave and shrapnel. Towards the end of World War II, the invention of the VT proximity fuze eliminated the need to use the fuze time calculation and its possible error. This greatly increased the odds of destroying an air target. Digital fire control computers were not introduced into service until the mid 1970s.

Central aiming from a gun director hasa minor complication in that the guns are often far enough away from the director to require parallax correction so they aim correctly. In the Mk. 37 GFCS, the Mkk1 / 1A sent parallax data to all gun mounts; each mount had its own scale factor (and "polarity") set inside the train (bearing) power drive (servo) receiver-regulator (controller).

Twice, in its history, internal scale factors were changed, presumably by changing gear ratios. Target speed had a hard upper limit, set by a mechanical stop. It was originally 300 knots, and subsequently doubled in each rebuild.

These computers were built by Ford Instrument Company, Long Island City, Queens, New York. The company was named after Hannibal C. Ford, a genius designer, and principal in the company. Special machine tools machined face cam grooves and accurately duplicated 3-D ballistic cams.

Generally speaking, these computers were very well designed and built, very rugged, and almost trouble-free, Frequent tests included entering values via the handcranks and reading results no the dials, with the time motor stopped. These were static tests. Dynamic tests were done similarly, but used gentle manual acceleration of the "time line" (integrators) to prevent possible slippage errors when the time motor was switched on; the time motor was switched off before the run was complete, and the computer was allowed to coast down. Easy manual cranking of the time line brought the dynamic test to its desired end point, when dials were read.

As was typical of such computers, flipping a lever on the handcrank's support casting enabled automatic reception of data and disengaged the handcrank gear. Flipped the other way, the gear engaged, and power was cut to the receiver's servo motor.

The mechanisms (including servos) in this computer are described superbly, with many excellent illustrations, in the Navy publication OP 1140.

There are photographs of the computer's interior in the National Archives; some are on Web pages, and some of those have been rotated a quarter turn.

2. 2. 4. Stable Element

Mark 6 Stable Element

The function of the Mk 6 Stable Element (pictured) in this fire control system is the same as the function of the Mk 41 Stable Vertical in the main battery system. It is a vertical seeking gyroscope ("vertical gyro", in today's terms) that supplies the system with a stable up direction on a rolling and pitching ship. In surface mode, it replaces the director’s elevation signal. [1] It also has the surface mode firing keys.

It is based on a gyroscope that erects so its spin axis is vertical. The housing for the gyro rotor rotates at a low speed, on the order of 18 rpm. On opposite sides of the housing are two small tanks, partially filled with mercury, and connected by a capillary tube. Mercury flows to the lower tank, but slowly (several seconds) because of the tube's restriction. If the gyro's spin axis is not vertical, the added weight in the lower tank would pull the housing over if it were not for the gyro and the housing's rotation. That rotational speed and rate of mercury flow combine to put the heavier tank in the best position to make the gyro precess toward the vertical.

When the ship changes course rapidly at speed, the acceleration due to the turn can be enough to confuse the gyro and make it deviate from true vertical. In such cases, the ship's gyrocompass sends a disabling signal that closes a solenoid valve to block mercury flow between the tanks. The gyro's drift is low enough not to matter for short periods of time; when the ship resumes more typical cruising, the erecting system corrects for any error.

The Earth's rotation is fast enough to need correcting. A small adjustable weight on a threaded rod, and a latitude scale makes the gyro precess at the Earth's equivalent angular rate at the given latitude. The weight, its scale, and frame are mounted on the shaft of a synchro torque receiver fed with ship's course data from the gyro compass, and compensated by a differential synchro driven by the housing-rotator motor. The little compensator in operation is geographically oriented, so the support rod for the weight points east and west.

At the top of the gyro assembly, above the compensator, right on center, is an exciter coil fed with low-voltage AC. Above that is a shallow black-painted wooden bowl, inverted. Inlaid in its surface, in grooves, are two coils essentially like two figure 8s, but shaped more like a letter D and its mirror image, forming a circle with a diametral crossover. One coil is displaced by 90 degrees. If the bowl (called an "umbrella") is not centered above the exciter coil, either or both coils have an output that represents the offset. This voltage is phase-detected and amplified to drive two DC servo motors to position the umbrella in line with the coil.

The umbrella support gimbals rotate in bearing with the gun director, and the servo motors generate level and crosslevel stabilizing signals. The Mk. 1A's director bearing receiver servo drives the pickoff gimbal frame in the stable element through a shaft between the two devices, and the Stable Element's level and crosslevel servos feed those signals back to the computer via two more shafts.

(The sonar fire-control computer aboard some destroyers of the late 1950s required roll and pitch signals for stabilizing, so a coordinate converter containing synchros, resolvers, and servos calculated the latter from gun director bearing, level, and crosslevel.)

2. 2. 5. Fire Control Radar

The fire-control radar used on the Mk 37 GFCS has evolved. In the 1930’s, the Mk 33 Director did not have a radar antenna. Then in September 1941, the first rectangular Mk 4 Fire-control radar antenna was mounted on Mk 33 and Mk 37 Directors, [18] becoming common in mid 1942. Soon aircraft flew faster, and in c1944 to increase speed and accuracy the Mk 4 was replaced by a combination of the Mk 12 (rectangular antenna) and Mk 22 (parabolic antenna) "orange peel" radars. (pictured) [16] in the late 1950s, Mk. 37 directors had Western Electric Mk. 25 X-band conical-scan radars with round, perforated dishes. Finally, the circular SPG 25 antenna was mounted on top.

2. 3. MK 38 Gun Fire Control System

The Mk38 Gun Fire Control System (GFCS) controlled the large main battery guns of Iowa class battleships. They were a major advance over the primitive radar sets used by the Japanese in World War II. The major components were the director, plotting room, and interconnecting data transmission equipment. The two systems, forward and aft, were complete and independent. Their plotting rooms were isolated to protect against battle damage propagating from one to the other.

2. 3. 1. Director

Mark 38 Director

The forward Mk38 Director (pictured) was situated on top of the fire control tower. The director was equipped with optical sights, optical Mark 48 Rangefinder (the long thin boxes sticking out each side), and a Mark 13 Fire Control Radar antenna (the rectangular shape sitting on top). [1] [19] The purpose of the director was to track the target's present bearing and range. This could be done optically with the men inside using the sights and Rangefinder, or electronically with the radar. (The fire control radar was the preferred method.) The present position of the target was called the Line-Of-Sight (LOS), and it was continuously sent down to the plotting room by synchro motors. When not using the radar's display to determine Spots, the director was the optical spotting station. [1]

2. 3. 2. Plotting Room

USS Missouri's Main Plot, c1950

The Forward Main Battery Plotting Room was located below the waterline and inside the armored belt. [1] It housed the forward system's Mark 8 Rangekeeper, Mark 41 Stable Vertical, Mk13 FC Radar controls and displays, Parallax Correctors, Fire Control Switchboard, battle telephone switchboard, battery status indicators, assistant Gunnery Officers, and Fire Control Technicians (FT's). [1] [19]

Mark 8 Rangekeeper

The Mk8 Rangekeeper was an electromechanical analog computer [1] [19] whose function was to continuously calculate the gun's bearing and elevation, Line-Of-Fire (LOF), to hit a future position of the target. It did this by automatically receiving information from the director (LOS), the FC Radar (range), the ship's gyrocompass (true ship's course), the ships Pitometer log (ship's speed), the Stable Vertical (ship's deck tilt, sensed as level and crosslevel), and the ship's anemometer (relative wind speed and direction). Also, before the surface action started, the FT's made manual inputs for the average initial velocity of the projectiles fired out of the battery's gun barrels, and air density. With all this information, the rangekeeper calculated the relative motion between its ship and the target. [1] It then could calculate an offset angle and change of range between the target's present position (LOS) and future position at the end of the projectile's time of flight. To this bearing and range offset, it added corrections for gravity, wind, Magnus Effect of the spinning projectile, stabilizing signals originating in the Stable Vertical, Earth's curvature, and Coriolis effect. The result was the turret's bearing and elevation orders (LOF). [1] During the surface action, range and deflection Spots and target altitude (not zero during Gun Fire Support) were manually entered.

Mark 41 Stable Vertical

The Mk 41 Stable Vertical was a vertical seeking gyroscope, and its function was to tell the rest of the system which-way-is-up on a rolling and pitching ship. It also held the battery's firing keys. [1]

The Mk 13 FC Radar supplied present target range, and it showed the fall of shot around the target so the Gunnery Officer could correct the system's aim with range and deflection spots put into the rangekeeper. [1] It could also automatically track the target by controlling the director's bearing power drive. [1] Because of radar, Fire Control systems are able to track and fire at targets at a greater range and with increased accuracy during the day, night, or inclement weather. This was demonstrated in November 1942 when the battleship USS Washington engaged the Imperial Japanese Navy battlecruiser Kirishima at a range of 18,500 yards (16,900 m) at night. [20] The engagement left Kirishima in flames, and she was ultimately scuttled by her crew. [21] This gave the United States Navy a major advantage in World War II, as the Japanese did not develop radar or automated fire control to the level of the US Navy and were at a significant disadvantage. [20]

The parallax correctors are needed because the turrets are located hundreds of feet from the director. There is one for each turret, and each has the turret and director distance manually set in. They automatically received relative target bearing (bearing from own ship's bow), and target range. They corrected the bearing order for each turret so that all rounds fired in a salvo converged on the same point.

Fire Control Switchboard

The fire control switchboard configured the battery. [1] With it, the Gunnery Officer could mix and match the three turrets to the two GFCSs. He could have the turrets all controlled by the forward system, all controlled by the aft system, or split the battery to shoot at two targets.

The assistant Gunnery Officers and Fire Control Technicians operated the equipment, talked to the turrets and ship's command by sound-powered telephone, and watched the Rangekeeper's dials and system status indicators for problems. If a problem arose, they could correct the problem, or reconfigure the system to mitigate its effect.

2. 4. MK 51 Fire Control System

Mark 51 Director with Mark 14 (40 mm) Gun Sight

The Bofors 40 mm anti-aircraft guns were arguably the best light anti-aircraft weapon of World War II., [22] employed on almost every major warship in the U.S. and UK fleet during World War II from about 1943 to 1945. [22] They were most effective on ships as large as destroyer escorts or larger when coupled with electric-hydraulic drives for greater speed and the Mark 51 Director (pictured) for improved accuracy, the Bofors 40 mm gun became a fearsome adversary, accounting for roughly half of all Japanese aircraft shot down between 1 October 1944 and 1 February 1945. [22] along with radar directed fire from 5 inch guns.

2. 5. MK 56 Gun Fire Control System (GFCS)

This GFCS was designed toward the end of World War II, apparently in response to Japanese kamikaze aircraft attacks. It was conceived by Ivan Getting, mentioned near the end of his Oral history, and its linkage computer was designed by Antonín Svoboda. Its gun director was not shaped like a box, and it had no optical rangefinder. It was manned by one officer, and had sliprings, permitting continuous rotation. (The Mk. 37 gun director had a cable connection to the hull, and occasionally had to be "unwound".) Fig. 26E8 on this Web page shows the director in considerable detail. The explanatory drawings of the system show how it works, but are wildly different in physical appearance from the actual internal mechanisms, perhaps intentionally so. However, it omits any significant description of the mechanism of the linkage computer.That chapter is an excellent detailed reference that explains much of the system's design, which is quite ingenious and forward-thinking in several respects.

In the 1968 upgrade to the USS New Jersey for service off Vietnam, three Mark 56 Gun Fire Control Systems were installed. Two on either side just forward of the aft stack, and one between the aft mast and the aft Mk 38 Director tower. [23] This increased New Jersey's anti-aircraft capability, because the Mk 56 system could track and shoot at faster planes.

2. 6. MK 68 Gun Fire Control System (GFCS)

5 inch Mark 42 gun turret

Introduced in the early 1950s, the MK 68 was an upgrade from the MK 37 effective against air and surface targets. It combined a manned topside director, a conical scan acquisition and tracking radar, an analog computer to compute ballistics solutions, and a gyro stabilization unit. The gun director was mounted in a large yoke, and the whole director was stabilized in crosslevel (the yoke's pivot axis). That axis was in a vertical plane that included the line of sight.

At least in 1958, the computer was the Mk. 47, an hybrid electronic/electromechanical system. Somewhat akin to the Mk. 1A, it had electrical high-precision resolvers instead of the mechanical one of earlier machines, and multiplied with precision linear potentiometers. However, it still had disc/roller integrators as well as shafting to interconnect the mechanical elements. Whereas access to much of the Mk. 1A required time-consuming and careful disassembly (think days in some instances, and possibly a week to gain access to deeply buried mechanisms), the Mark 47 was built on thick support plates mounted behind the front panels on slides that permitted its six major sections to be pulled out of its housing for easy access to any of its parts. (The sections, when pulled out, moved fore and aft; they were heavy, not counterbalanced. Typically, a ship rolls through a much larger angle than it pitches.) The Mk. 47 probably had 3-D cams for ballistics, but information on it appears very difficult to obtain.

Mechanical connections between major sections were via shafts in the extreme rear, with couplings permitting disconnection without any attention, and probably relief springs to aid re-engagement. One might think that rotating an output shaft by hand in a pulled-out section would misalign the computer, but the type of data transmission of all such shafts did not represent magnitude; only the incremental rotation of such shafts conveyed data, and it was summed by differentials at the receiving end. One such kind of quantity is the output from the roller of a mechanical integrator; the position of the roller at any given time is immaterial; it is only the incrementing and decrementing that counts.

Whereas the Mk. 1/1A computations for the stabilizing component of gun orders had to be approximations, they were theoretically exact in the Mk. 47 computer, computed by an electrical resolver chain.

The design of the computer was based on a re-thinking of the fire control problem; it was regarded quite differently.

Production of this system lasted for over 25 years. A digital upgrade was available from 1975 to 1985, and it was in service into the 2000s. The digital upgrade was evolved for use in the Arleigh Burke class of destroyers. [24]

AN/SPG-53

Mark 68 GFCS director with AN/SPG-53 radar antenna on top.

Country of origin

United States

Type

Gun fire-control

Precision

Fire control quality, three dimensional data

The AN/SPG-53 was a United States Navy gun fire-control radar used in conjunction with the Mark 68 gun fire-control system. It was used with the 5"/54 caliber Mark 42 gun system aboard Belknap-class cruisers, Mitscher-class destroyers, Forrest Sherman-class destroyers, Farragut-class destroyers, Charles F. Adams-class destroyers, Knox-class frigates as well as others.

2. 7. MK 86 Gun Fire Control System (GFCS)

Mk 45 lightweight gun turret

The US Navy desired a digital gun fire-control system in 1961 for more accurate shore bombardment. Lockheed Electronics produced a prototype with AN/SPQ-9 radar fire control in 1965. An air defense requirement delayed production with the AN/SPG-60 until 1971. The Mk 86 did not enter service until when the USS California nuclear powered missile cruiser was commissioned in February 1974, and subsequently installed on US cruisers and amphibious assault ships. The last US ship to receive the system was commissioned in July 1994. [25]

The Mk 86 on AEGIS class ships controls the ship’s 5"/54 caliber Mk 45 gun mounts, and can engage up to two targets at a time. It also uses a Remote Optical Sighting system which uses a TV camera with a telephoto zoom lens mounted on the mast and each of the illuminating radars.

2. 8. MK 34 Gun Weapon System (GWS)

USS Arleigh Burke (DDG-51)

The MK 34 Gun Weapon System is an integral part of the Aegis combat weapon system on Arleigh Burke-class guided missile destroyers, the only operational class of destroyers in the US. It combines the MK 45 5"/54 Caliber Gun Mount, MK 46 MOD 0 Optical Sight System and the MK 160 Mod 4 Gunfire Control System / Gun Computer System. It can be used against surface ship and close hostile aircraft, and as Naval Gunfire Support (NGFS) against shore targets. [26]

2. 9. MK 92 Fire Control System (FCS)

Mk 75 gun

The Mark 92 fire control system, an Americanized version of the WM-25 system designed in The Netherlands, was approved for service use in 1975. It is deployed onboard the relatively small and austere Oliver Hazard Perry-class frigates to control the MK 75 Naval Gun and the MK 13 Guided Missile Launching System (missiles have since been removed since retirement of its version of the Standard missile). The Mod 1 system used in PHMs (retired) and the US Coast Guard's WMEC and WHEC ships can track one air or surface target using the monopulse tracker and two surface or shore targets. FFG 7 class frigates with the Mod 2 system can track an additional air or surface target using the Separate Track Illuminating Radar (STIR). [27]

2. 10. Mk 110 57 mm gun

The Mk 110 57 mm gun is the newest multi-purpose, medium caliber gun. It's based on the Bofors 57 Mk 3. Compared to WWII destroyers or escorts fitted with 2 or 5 five-inch guns which could fire 15 rounds per minute per barrel, the single Mk 110 can fire salvos at up to 220 rounds per minute, up to a similar range of nine miles with minimal manpower in a turret with a stealthy radar signature. Linked to a digital fire control system, servo-controlled electro hydraulic gun laying subsystems provide extreme pointing accuracy, even in heavy seas. Current and proposed mountings for the weapon include the United States Coast Guard's National Security Cutter, the upcoming Zumwalt class destroyer (close-in), and the new Littoral combat ships. [28]

To increase lethality and flexibility, the ammunition comes equipped a smart programmable fuze with six modes: contact, delay, time, and 3 proximity modes.

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Russian WWI Naval Air

Posted on December 01 2009 at 06:54 PM

Grigorovich M-5

This aircraft based on the seaplane carrier Imperator Alexander I. Black Sea Fleet.

Grigorovich M-9

Black Sea Fleet.

The other –than the Royal navy - great exponent of carrier aviation during World War I was the Imperial Russian Navy in the Black Sea. From early 1915 the Black Sea Fleet mounted a sustained interdiction campaign against Turkish sea communications. A particular target was the coal trade from Anatolia to Constantinople on which the Turkish- German fleet largely depended and that had to come by sea because there was no rail line and the road system was inadequate. According to Russian claims, their naval forces sank over 1,000 vessels during this campaign, in which the fleet’s aircraft carriers played a central role and must have been directly responsible for an appreciable percentage of these successes. On more than one occasion the battle cruiser Goeben and the light cruiser Breslau, units technically transferred to the Ottoman Navy from the German fleet but actually commanded and manned by Germans, that formed the modern heart of Turkish naval forces were incapable of putting to sea on operations for lack of fuel reserves.

The three carriers converted in early 1915 were fast enough to maintain formation with the older battleships that initially formed the core of the fleet and could keep up with even the new dreadnoughts that joined the fleet later. Consequently, there were few operations of any size in which the carriers were not tightly integrated and in several of those against the Anatolian and Bulgarian coastlines, the carriers formed the principal striking force with the battleships relegated to support and distant cover roles. Russian carriers used Curtiss flying boats initially, which eventually were supplanted by excellent indigenous Grigorivich boats. The carriers carried large numbers of aircraft for the period and their crews were highly trained, so their launch rates were impressive. One American observer timed a carrier launching seven aircraft in fifteen minutes, compared with the Royal Navy’s standard of twenty minutes to launch three aircraft (admittedly under North Sea conditions). After 1916, when Romania joined the war, the Black Sea Fleet’s aircraft carrier strength increased when one Romanian auxiliary, the Rominia, joined the fleet as a full-time carrier and was supplemented periodically by four other auxiliary cruisers embarking aircraft as operationally necessary. The carriers’ aircraft attacked Turkish and Bulgarian ports, their facilities, and ships at dock, conducted widespread reconnaissance missions, raided coastal shipping, bombed shore installations, spotted for the fleet’s guns, and provided cover for mine-laying operations and convoys.

By the end of World War I, naval aviation had secured for itself an important place in operations. For the most part, however, naval aircraft were shore based. While operational experience had confirmed the potential value of carrier-based aviation, the technical and functional details necessary for success remained immature. Major navies accepted that aircraft carriers were an essential feature of future fleets but the shape, size, arrangements, facilities, and equipment all were uncertain and still required much experiment and testing.

RUSSIA: ALMAZ (1915)

Builder: Baltic Works, St. Petersburg

Laid down: September 25, 1902. Launched: June 2, 1903. Commissioned: 1915

Displacement: 3,285 tons (normal)

Dimensions: 363’0” (oa) x 43’6” x 17’6” (mean)

Machinery: Vertical triple-expansion engines, Belleville boilers, 2 shafts, 7,500 ihp = 19 knots

Aircraft: 4

Armament: 7 x 4.7”, 4 x 12 pdr AA

Complement: 340

Design: Originally completed as an armed yacht rated as a third-class cruiser, the Almaz served as the viceregal yacht in the Far East and was the largest Russian survivor of the Battle of Tsushima (May 27-29, 1905). The Almaz was transferred to the Black Sea Fleet in 1911 and refitted as a seaplane carrier early in 1915. Seaplane handling platforms were fitted behind the mainmast and additional booms were rigged for lifting aircraft. Service: The Almaz formed part of the Hydro-Cruiser Division of the Black Sea Fleet from 1915 to 1917. As the fastest of the fleet’s seaplane carriers, it often undertook independent missions, including raids on Varna in Bulgaria in October 1915 and June 1916. After the popular revolution in 1917 the Almaz became a Bolshevik headquarters ship but was seized by French forces at Odessa in December 1918 and turned over to White Russian forces. It sailed to Algiers in 1920 with other White Russian vessels, was taken over there by the French in 1928, and scrapped in 1934.

RUSSIA: CONVERTED MERCHANTMEN (1915)

Builder:

Imperator Nikolai I: John Brown & Company Ltd., Clydebank

Imperator Alexandr I: William Denny & Brothers Ltd., Dumbarton

Displacement: 9,230–9,240 tons (normal)

Dimensions: 381’0” (oa) x 52’0” x 26’0” (mean)

Machinery: Vertical triple-expansion engines, 4 boilers, 2 shafts, 5,100 ihp = 13.5 knots

Aircraft: 8

Armament: 6 x 4.7”, 4 x 12 pdr AA

Complement: Unknown

Design: These two vessels were built as fast cargo liners for the Russian Steam Navigation Trading Company and completed in 1913 and 1914, respectively. They were requisitioned as naval auxiliaries after the outbreak of World War I and converted into seaplane carriers in early 1915. The conversion was minimal, involving fitting additional booms for aircraft handling and clearing after superstructure space to make room for aircraft stowage on the upper deck. Service: These vessels formed the core of the Black Sea Fleet’s Hydro- Cruiser Division and were very active against Turkish and Bulgarian coastal targets from March 1915 to February 1917. After the popular revolution they were renamed the Aviator and the Respublikanetz, but were laid up from April 1917 until they were taken over by French forces in December 1918. Both vessels entered French commercial service after World War I, serving with the Compagnie des Messageries Maritimes as the Pierre Loti and the Lamartine. The Pierre Loti was wrecked in the Gabon River estuary in 1943 and the Lamartine, by then renamed the Khaidinh, was sunk by United States Navy aircraft in Along Bay in 1942.

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First Non-American Turreted Ironclads

Posted on November 26 2009 at 09:27 AM

This idealized picture of the Captain off Gibraltar illustrates the high regard in which the public held the ship and her designer, Captain Cowper Coles, who lost his life when she went down a few months later.


HMS Devastation the first mastless battleship designed by Sir Edward Reed. While her breastwork layout and low freeboard might have made her unsuitable for ocean fighting) she was well adapted to defence and attack of naval bases) which figured prominently in 1870s strategy.


The development whose first manifestation occurred in the American Civil War was the turret-ship. This was a concept which turned out to be much sounder than the ram. The idea of mounting the ship's heaviest gun or guns on a turntable that could rotate to fire on any bearing except, of course, where it would interfere with the structure of one's own ship had occurred to designers other than Ericsson, notably Captain Cowper Coles of the Royal Navy. Coles's turret design, with the gun mounting rotating on a roller path, was inherently better than Ericsson's which turned on a central stalk, and it was incorporated in a Danish warship, the Rolf Krake, in the mid 1860s, and not long after in a radically modified British line-of-battle ship, the Royal Sovereign. This ship was for experimental purposes only but much was learnt.

Not, however, enough. An argument broke out between Coles and the Admiralty authorities as to the best design for a full-scale operational turret-ship, and eventually one of each was authorized. Both sides to an extent got it wrong, for both specified a full sailing rig, even though steam technology was becoming more reliable by the year. But with the Captain Coles, compounded by the shipbuilders Laird's, got it much more wrong than Reed with the Monarch. The Captain had very low freeboard even as designed, and much lower when completed because of weight added during building; it was calculated that her stability vanished at an angle of heel of not much more than 40 degrees. Yet she was the darling of the Press, wholl1 Coles had assiduously wooed. On the first two or three occasions she went to sea she seemed to behave well enough, but she capsized in a Bay of Biscay gale on 6 September 1870.

The Monarch by contrast was stable and seaworthy, though she did not handle well under sail alone. Reed, her designer, never much liked the concept, and was much happier with his first 'mastless' turret-ship, the Devastation, which came into service only a short time after the Monarch in 1871. This vessel was the prototype of the Victorian battleship as the world came to know it: of low profile, broad-beamed, heavily armoured, its main guns in twin turrets forward and aft, with only a 'military mast' for flag signalling and no motive power other than steam.

In spite of the pattern that was then set, hull design proceeded by fits and starts for the next two decades, which have rightly been called the 'groping age' in warship design. Partly this was due to a belt-and-braces attitude in the users: they did not want to move to a navy reliant entirely on steam, a development which was considered too risky for them to contemplate. In consequence some battleships continued to appear during the 1870s with full sailing rigs which looked increasingly incongruous; at least one ship, Inflexible, the pride of the fleet, had instructions to ditch all masts and sails if she went into action. Turrets, too, were not regarded as the only sensible way of deploying big guns; the broadside battery was still favoured by many, and centre-battery ships were brought into service for several years after the appearance of the Devastation. The belt-and-braces approach was carried furthest in the Temeraire, a fully brig-rigged ship with centre-battery guns and two turrets. This ultimate hybrid came into service in 1877.

Things were no less tentatively managed on the Continent. The French built only eight battleships in the 1870s, less than half the number achieved by the British and of equally experimental design. The Russians were exceptionally enterprising, building some craft of extraordinary design culminating in the charmingly named 'popoffkas', almost completely round in plan. The Italians under their great designer Benedetto Brin produced some fast, powerful battleships that certainly influenced thinking worldwide, including Britain. Brin's attitude to armour was of particular interest: he favoured a central citadel with very little armour at either bow or stern, and this pattern was in essence adopted by the British chief designer Barnaby for some years around 1880 - much to the chagrin of Reed, who had retired but voiced dissent from the sidelines.

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NR-1 Submarine Dives Into History

Posted on November 12 2009 at 12:49 AM


November 26, 2008

GROTON, Conn. - The unique, compact undersea research and ocean engineering submarine NR-1 held its inactivation ceremony at Naval Submarine Base New London.

NR-1 highlighted her career with multiple missions to search for artifacts, wrecks and mapping of the ocean floor. She had recovered weapons from the ocean floor in 1976, discovered three wrecks along the Mediterranean trade route at the Skerki Bank in 1995, surveyed the remains of the USS Monitor and USS Akron in 2002, and explored the Flower Garden Banks in the Gulf of Mexico in 2007. Her final mission in 2008 was a hunt for the wreck of the Bonhomme Richard, the flagship of naval hero John Paul Jones.

The keynote speaker, retired Adm. Edmund Giambastiani, was one of many former members in attendance. He was the officer-in-charge from May 1982 to April 1985. "NR-1 provided a tremendous scope for innovation and invention," said Giambastiani. "She truly was a window to the world under the sea."

NR-1's keel was laid June 10, 1967 and launched in 1969. It is 150-feet long and weighs 450 tons, with special features including retractable wheels, three viewing windows, low-light cameras and recovery systems with a manipulator arm.

"She is truly a testament to the foresight of her builders and designers," said Cmdr. John McGrath. "It's a bittersweet moment, but an honor to be the one to help say goodbye."

NR-1 will be towed to Portsmouth Naval Shipyard in Kittery, Maine to start the inactivation process in December 2008. Following completion process at Portsmouth Naval Shipyard, the ship will then be transported to Puget Sound Naval Shipyard.

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Origins: Special Attack Submarines

Posted on November 06 2009 at 03:24 AM

A model of the British X-craft.

The prototype of the human torpedo (or, for that matter, of the midget submarine) was conceived by an Englishman, Commander Godfrey Herbert, R.N. (retired), as early as 1909. The design of the "Devastator" was for a one-man torpedo, which was to be fitted with a detachable buoyant compartment for the vessel's navigator. In the words of the patent: ". . . it had for its object to provide means for propelling against an enemy ship or other target a large quantity of high explosive, and of effecting this with great economy of material and personnel."

This was the idea that Herbert suggested to the Admiralty before and during the First World War, only for it to be turned down by, among others, the pre-1914 First Lord and First Sea Lord, Mr. Winston Churchill and Prince Louis of Battenberg respectively. They described it as being too dangerous for the operator and the weapon of a weaker power. The idea was modified and resubmitted by Max Horton (then a captain), but to no avail. Perhaps, as Horton was proposing to operate the "Devastator" himself, the Lords Commissioners were thinking, too, that he was more valuable to his country as a senior submarine officer.

Another design, this time for a three-man submarine, was incorporated in his Diving Manual and patented in 1915 by Robert H. Davis of Siebe, Gorman and Co., Ltd. (later Sir Robert Davis and chairman of that company). This project included an escape compartment such as was adopted more than twenty-five years later in all the X-class submarines.

The next development came from Max Horton again, who produced a threefold suggestion for the construction of very small submarines in 1924. He was then Captain (S) at Fort Blockhouse. His idea consisted, first of all, of the Type "A" submarine, of between 30 and 40 tons' displacement. This craft would have had a detachable conning tower-a development of Herbert's buoyant compartment-and would have been carried to the area of operations by a surface vessel. Type "B" was to consist of a "miniature submarine, to contain a crew of two, and to be fixed to but detachable from a bi-lobular main hull in which would be situated the main engines and the explosive head." This suggestion would again have been of about 40 tons' combined displacement.

The design which most nearly succeeded in winning official approval was Type "C." This was for a small submarine, of the same approximate displacement as Types "A" and "B," which would carry a large, short-range, heavy-headed torpedo slung outside and underneath the hull in a recess. This design had the supreme advantage of being the only one of the three in which the main hull, containing the crew, would remain under mechanical power after the attack had been made. As has been said, this type was the one most preferred by the authorities, almost entirely because of the advantage of possible recovery. But the major serious objection to the adoption even of Type "C" was that, in addition to the admitted risk to the operators, the employment of the craft would necessitate the use of a special carrier vessel which would have to proceed unwarrantably close inshore.

A fourth idea was that conceived by Commander Cromwell Varley, D.S.O., R.N. (retired), in the interwar years. At the end of the First World War Commander Varley was in command of the submarine L.1. In the 1920's he was retired under one of the several schemes for cutting naval personnel, which event caused him to adapt his talent for marine engineering to the commercial field. It was during the 1930's that his ideas for a midget submarine first took shape in his mind. His initial plan was for a craft some 26 feet in length, to carry a crew of two. Nearer the crucial year of 1940 he modified his early ideas, extending the over-ail length to 50 feet, increasing the crew to three, and embodying Sir Robert Davis's escape compartment.

Varley's idea was accepted by the Admiralty, largely in the person of Max Horton, in 1940. This was partly due to Sir Max's own enthusiasm for Varley's suggestions; partly to Varley's own selling efforts; partly to the representations of Colonel Jefferis (a prewar associate of Varley's), some of which reached Mr. Churchill; and partly-very largely, indeed-owing to the fact that Max Horton and Godfrey Herbert were already investigating ways of carrying out submarine attacks against enemy capital units in Norwegian harbors.

The strategic reasoning behind the final acceptance of the idea was doubtless based upon Max Horton's own views upon the subject as expressed in some of his written notes:

The need calling for this type of submarine is due to the less effective potential hurt that the ordinary modem submarine and torpedo are capable of inflicting on a modern capital ship, together with the increasingly effective defensive measures against submarines endeavoring to bring off a close attack. A weapon for such a purpose (to attack the enemy battle fleet when in harbour) has been looked for without real success for many years. Equipped with cutters and a stout hull, this small submarine could choose its depth to penetrate harbour defences.

This, therefore, was the history that led up to the development of the first human torpedo, and the first X-craft, as told in the foregoing chapters. Incidentally, it was necessary that the first X-craft should be numbered X.3. X.1 had been an experimental giant submarine with a twelve-inch gun that had been scrapped by the Navy as being impracticable; and X.2 had been a captured enemy vessel.

Even after X.3 had been approved her development was full of anomalies. For instance, it was typical of the whole set of circumstances in which she came into being that she should have been built by a private company, Varley Marine Limited, and not by a naval dockyard. It was typical, too, that Commander Varley should never re-enter the Navy, but should design and build the Navy's most secret project, be called Commander by all who met him, and yet wear a thick tweed suit among all the uniforms.

Parallel to the early development of the first JST-craft, the "W and D" escape compartment had been rigorously tested. A steel "mock-up"-consisting of escape chamber and adjoining watertight compartment-had been constructed as early as 1940, and had been put through its paces in the 60-foot deep torpedo-testing tank at Portsmouth, where Captain Herbert, Commander Varley, Professor Haldane (of the Experimental Diving Unit), and Colonel Jefferis had gone down, two at a time, to conduct various experiments.

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S-Boot Camo

Posted on October 21 2009 at 03:45 AM

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LOSS OF ARMORED SHIPS: BATTLE OFTSUSHIMA

Posted on October 07 2009 at 07:01 AM

Borodino

(from reminiscences of a participant of the battle)

"Prince Suvorov"

The flag armored ship路 "Prince Suvorov" became the main target of the first five Japanese ships, having circled round after turning in succession and setting on parallel course. She was disabled simultaneously with "Osl'abia" because of damage of steering wheel in the conning house. She had the mainmast and after funnel down, the aft 75-mm gun tower burst, its top thrown down and lying on the aftercastle. All the 57-mm guns were out of action, all the unprotected side sections were destroyed, the underwater hull under the conning house was shot-holed. The ship was enveloped completely in flames, a dense cloud of smoke was following her over the water. She was still afloat, her engines worked, allowing her to move after the squadron; she crossed twice the line. After 5 p. m. two her funnels and masts were down. Her silhouette was disfigured beyond recognition, so our end ships, unaware of her leaving the line, took her for some injured Japanese ship and even gun-fired her.

At 5 p. m. the wounded vice-admiral and 19 officers were taken away from "Suvorov" by the destroyer "Buiny". At this time only 47 mm-gun of the after casemate was able to fire. By making the signal on the board of "Bystry" the admiral informed the squadron about turning the command over to admiral Nebogatov.

Helpless and abandoned by the squadron, the flagship was attacked at 7.29 p. m. by the division of enemy's destroyers, that got to close quarters, and took the direct hit by four torpedoes. Not far from "Suvorov", the transport ship "Kamchatka" was sunk, that had tried to help her. The heroic flagship went down with her captain, officers and crew; only vice-admiral and officers of headquarters were saved by "Buiny".

"Emperor Alexander III"

After the flagship "Suvorov" was disabled, the armored ship "Alexander III" became the head ship and undertook the daring attempt to break through northwards, passing the end of the Japanese division, having come ahead. However this maneuver was frustrated because of sudden turning 16 points together of the entire enemy's column, which crossed the course of "Alexander III". This ship left the line temporarily, but soon resumed her place at the head of the column and continued to be there till 3.40 p. m., when severely damaged and enveloped in flames, she left the line and went to the end of the column, taking place between "Nakhimov" and "Dshakov". After 5 p. m. "Alexander III" was gun-fired by Japanese armored cruisers from the port side. At 6.50 p. m. she left the line, making the signal "Ship in distress". Having the great list, the ship fired salvo of middleship 57 mm-gun turret and was on her beam-ends. When she capsized, her hull was floating some time, her keel over. Several tens of men perched on the ship bottom; they might be saved, but all of them sank with the ship.

"Borodino"

In the first phase of the battle, before the attempt of break-through to the north, "Borodino" had few insignificant damages. "Alexander III" leaving the line, "Borodino" became the head ship and in her turn repeated the attempt to break through northwards, passing the end of the Japanese division. Making use of temporary absence of Japanese ships, which moved southwards and lost the Russian squadron in the mist, at 5 p. m. "Borodino" collected the rest of Russian ships and led them northwards. When Japanese armored ships, that returned from the south by parallel course, overhauled our column, "Borodino" took a terrible poundering from starboard, but continued to keep for Vladivostok, without any evolutions. She was enveloped in flames. Her last hour "Borodino" moved with 5掳 list to the enemy side. From the bridge of the armored ship "Orel", following her, one could see continuous hits of 76 mm shells against her waterline, causing huge fountains to rise. Through ports of batteries bright flame was shooting up. In the last moment the shell struck the side under the after 57 mm-gun turret. Probably it caused burst in bunkers, for the flame appeared near the waterline, and the ship was in a minute on her starboard beam-ends. The ship capsized: About 30 men perched on the bottom of turned-over ship, but in the result of some internal burst, the hull went down and all the seamen perished. By night the Japanese destroyer picked up one man of this crew, who was the only survived member of crew of this heroic ship.

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[typ] M23 & M24 TORPEDO BOATS - Raubvogel (1923) and Raubtier (1924)

Posted on September 21 2009 at 05:19 AM

Initially classified as destroyers, the 'Typ 23' [M23]torpedo boats saw considerable action in the North Sea and Channel. Armed primarily for surface action, they were the first flotilla craft built for the Weimar navy.

Raubvogel class Shown here in its early 1930s form, this torpedo boat is finished in the typical black early colour scheme. The foremost and sternmost open gun mounts have been replaced by enclosed turrets; the raised stern mount - only marginally more protected in heavy seas - is still open to the elements. By the late stages of the war the surviving members of this early class of torpedo boats had all of their main armament in turrets, carried radar antennae on both masts, and mounted increased anti-aircraft armament.

Typical open gun mount found on the early torpedo boats. The weapon is a 10.Scm L/4S, introduced in 1932 but based on a design dating back to before World War I. It had a rate of fire of 15 rounds per minute, firing a 24kg shell at a muzzle velocity of 780 metres per second.

Now enclosed in a turret, the main armament fitted to later types of torpedo boat - the 10.5cm L/4S (/32 - was basically the same as the earlier piece. Note the raised armoured flap, dropped when not in use to protect the delicate sighting optics.

The six 'Mรถwe' class (officially 'Typ 23') ships were the first flotilla craft built by the 'new' German navy; they were strictly torpedo boats and, despite their modest size, carried two triple mountings. Though this class of ship was not designed to undertake fleet duties, the lack of any alternative at that time probably accounted for their comparatively high speed. Three boilers were required in the slim hull, necessitating two widely-spread funnels, which made them look larger than they actually were. They carried three old, but effective 105-mm (4.13- in) guns which, together with the ambitious torpedo fit, brought up the topweight allowance to the extent that (unusually for the German navy) mines could not be carried in addition. While the 'Mรถwes' were still building, a second group of six, the slightlyenlarged 'Wolf class (Typ 24) ships were ordered. Though of the same calibre, their main armament was of an improved pattern.

The ships were heavily involved in near-coastal waters during the war, gradually acquiring more light automatic weapons, some at the expense of a set of torpedo tubes. Following these two classes, subsequent development went for larger torpedo boats and smaller S-boats. Neither of these types was viewed as an ideal escort, leaving the way clear for introduction of the specialist Geleitboote.

All these torpedo boats were active during the Spanish Civil War as part of Germany's 'non-intervention' patrols. All vessels of both classes were also involved in escort work for the invasion fleet during the attack on Norway in April 1940. By the end of that campaign four of the 12 vessels had been lost, and the remaining eight were thereafter grouped together in 5. Torpedobootsflottille. During the second half of 1940 the flotilla was heavily involved in minelaying operations in the English Channel, and also in 'hit and run' attacks on British merchant shipping.

Five of these warships - Seeadler, Kondor, Falke, litis and Jaguar - were also involved in Operation 'Cerberus' (the 'Channel Dash'), escorting the battleships Scharnhorst and Gneisenau and the heavy cruiser Prinz Eugen during their run eastwards through the English Channel in February 1942; Jaguar was severely damaged by British aircraft during this operation. On 14/15 May 1942, Seeadfler, litis, Kondor and Falke formed part of the escort screen for the auxiliary cruiser Stier as she broke out into the Atlantic through the Channel. The German ships came under fire from both longrange coastal artillery at Dover and from British MTBs, and both litis and Seeadler were sunk. The remainder of these elderly boats continued to give good service until the summer of 1944, when they were all destroyed in Allied bombing raids connected with the Normandy invasion.

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