Petr Velikiy (1877)

Russia (1877)
Ironclad

The ironclad babochka

The Petr Velikiy (Peter the Great) was undoubtedly the oldest Russian battleship in service in 1914, the babochka (“Grandma”) of the Russian navy. This battleship knew several lives. It was in its day the very first Russian battleship with turrets and steam alone, a fashion launched by France and Great Britain and quickly followed by the tsar for the Baltic fleet.

Petr Velikiy in service in the late 1870s
Petr Velikiy in service in the late 1870s

The Russian Ironclad

Probably the biggest and most modern Russian warship drawn in the late 1860s, the Пётр Великий – Peter the Great, was an ironclad turret ship, started in july 1870 at Galerniy Island Shipyard, Saint Petersburg and launched 27 August 1872, for over 5.5 million rubles. The plans betrayed a strong British influence, notably the contemporary HMS Dreadnought (1st) class ironclad of similar configuration, but was initially inspired by the American twin-turret monitor USS Miantonomoh when visiting Kronstadt in August 1866. Rear Admiral A. A. Popov was its designer, and initially proposed a low-freeboard breastwork monitor with full rigging. Peter the Great was completed however in 1876 with a revised design.

From monitor to sea-going Ironclad

From the initial hybrid monitor-cruiser design, submitted to the Naval Technical Committee in 1867, the design evolved as it was ordered the coal carried to be raised from four to five days steaming, triggering design modifications. The design was revised 26 January 1869, but other changes were added by Popov himself, like a central superstructure forward of the breastwork to improve seakeeping and overhanging side armor. The revised design was again submitted and approved in 19 June 1869 but meanwhile the displacement made a jump from 7,496 long tons to 9,462 long tons. While building started, new changed were made to “Kreiser” (cruiser), the rigging was deleted, spar torpedoes added, and after a visit and advice from naval architect Edward Reed, armour was increased to 14in (356 mm). The ship was then renamed in 1872 to celebrate the bicentennial of Peter the Great, founder of the Baltic feet.

Design

Popov’s ironclad was just 100.5 m long at the waterline (330 feets), and on completion her displacement rose to 10,406 long tons (10,573 t). For rigidity and protection, she was subdivided by one centerline and longitudinal, nine transverse and two wing watertight bulkheads, plus complete double bottom. She had a low freeboard and rolled a lot, generally considered as a passable sea-boat. She also had two three-cylinder horizontal return connecting rod-steam engines, each with a propeller. Each was fed by 12 rectangular boilers (36 psi) for a total of 9,000 nominal horsepower (6,700 kW) and a top speed of 13 knots (24 km/h; 15 mph) and 1900 nm of range thanks to a reserve of 1230 tons of coal. Boilers proved of frail construction and showed numerous defects, as built by Scottish-funded St Petersburg Baird Works. Sea trials showed it could only reach 11 knots, and the chimney was raised by about 20 feet, but with little effect.

The main armament comprised four muzzle-loading smoothbore 20-inch (508 mm) guns (US. Rodman design), but eventually, an enlarged version of the German 280mm Krupp was chosen, to produce a 12-inch, 20-caliber type. Rather than the muzzles, the hydraulic turret machinery raised and lowered the guns’ trunnions. Range, at 12.5° was 5,800 yards (5,300 m). The 360 long tons (370 t) Coles type turrets fully revolved in a minute although because of the superstructure, only 310° was practical. Secondary armament was defensive against torpedo-boats, six 4 pdr (3.4-inch (86 mm)) guns (4 bridge, 2 stern), and two Palmcrantz 1 pdr (1-inch (25 mm)) Gatling-type machine guns. There were in addition four telescopic spar-torpedoes mounted in the bow, which mostly acted as a ramming deterrent for other ships.

First service period (1877-1905)

Early on, in the context of the Russo-Turkish war of 1877 and British threat, two 9-inch mortars were fitted on her quarterdeck, later removed in 1880. After many complaints about the machinery (Baird works received a penalty), John Elder & Co., in Glasgow, Scotland, in October 1880 was contracted. Refitting lasted to February 1882. In addition to be reliable and lighter, the machinery allowed the ship to reach 14.36 knots (26.59 km/h; 16.53 mph).

She departed Scotland for a Mediterranean cruise, visiting many ports, then headed north, before reaching Kronstadt on 12 September. In the mid-1880s two 44-millimeter (1.7 in) Engstrem guns replaced the rear deck 4 pdrs, her boilers were replaced in 1892, and by the mid-1890s, four additional 4-pdr were added to each turret, plus six 47 mm (1.9 in) 5-barrel revolving Hotchkiss guns (bridge) four 37mm (1.5 in) Hotchkiss guns (deck). Considered obsolete by then, several reconstruction proposals were made. Eventually, this was postponed until a new minister of the Marine came at the office and decided to convert her as a gunnery training ship.

Petr Velikiy as rebuilt
Petr Velikiy as rebuilt

Reconstruction (1905)

The reconstruction plan was approved on 2 February 1904. In 1905-1906 she was entirely rebuilt, with new machines and boilers, two chimneys, two light masts, a high freeboard thanks to a completely redesigned hull, a displacement reduced to 9790 tons and a new armament: Exit the antique 305mm, the artillery now included 4 x 203 mm on the upper deck at the four corners, and 12 x 152 mm on the lower deck in casemates. The rest consisted of small pieces on the main deck.

Petr Veliky was now 321 feet 10 inches (98.09 m) long overall, 62 feet 4 inches (19.0 m) wide, with a 26 feet 7 inches (8.1 m) draft. Displacement was reduced to 9,790 long tons (9,950 t). Top speed was 12.9 knots (23.9 km/h; 14.8 mph) for 714 long tons (725 t) of coal and 1,500 nautical miles (2,800 km; 1,700 mi) range.

The Petr Velikiy at war (1914-18)

She was completed the following year of the Russo-Japanese war. She was in 1914 assigned to the Baltic fleet, but played a secondary role, mainly coastguard and part of the Gunnery Training Detachment through 1917 as planned.

In February 1917 she could have been was renamed Respublikanets or Barrikada (Barricade), by the Soviets (still unconfirmed). Retired afterwards, she was completely disarmed in October 1918 and converted as a depot ship for submarines at Kronstadt, then Helsinki. It was subsequently used as a mines carrier and was renamed Barrikada. Hulked on 21 May 1921 she was used to store mines. Renamed Blokshiv Nr. 1 on 4 December 1923 she was forced aground in shallow water by autumn floods in September 1923. She was refloated and repaired in 5 October 1927 and in January 1932 renamed Blokshiv Nr. 4, then BSh-3 (1949) barrack ship at Kronstadt. She was eventually stricken on 18 April 1959 and scrapped, after a 80+ years long career.

Specifications (1914)

Dimensions (L-w-h) 101.7 x 19.2 x 7.5 m 333’8”x63′ x24’9”
Total weight, fully loaded 10,406 long tonnes
Armament 2×2 305mm (12 in), 6x 4pdr, 2x 1pdr HMG, 4 spar Torpedoes
Armor Belt: 8–14 in (203–356 mm)
Citadel: 14 in (356 mm)
Deck: 2.5–3 in (64–76 mm)
Gun turrets: 14 in (356 mm)
Crew 24 officers + 417 sailors
Propulsion 2 shafts, 2 HRC rod-steam engines, 12 rectangular boilers, 8,258 ihp (6,158 kW)
Speed (road) 13 knots (24 km/h; 15 mph)
Range 2,900 nm (5,400 km; 3,300 mi) @10 knots (19 km/h; 12 mph)

Gallery


Illustration profile of the Petr Veliki as of 1914


Petr Velikiy on a stamp from 1974.

Delaware class battleships

USA (1908)
USS Delaware, North Dakota


USS North Dakota

The Delaware class in short

Dreadnought battleships of the Delaware class were launched in 1909 and completed in 1910, and can be seen as the first “true” dreadnoughts of the American Navy, since the preceding South Carolina were a bit of compromise between the old and new designs. They were in tonnage, dimensions, and especially speed, more in line with this type of modern battleship.

-The USS Delaware (BB-28) was laid down at Newport News Shipbuilding, 11 November 1907, launched 6 February 1909 commissioned 4 April 1910, and decommissioned on 10 November 1923, Broken up at Boston the next year.
-The USS North Dakota (BB-29) was laid down 16 December 1907 at Fore River Shipyard, Quincy, launched 10 November 1908 and commissioned 11 April 1910. It was decommissioned 22 November 1923 and Broken up at Baltimore, 1931.

Design

In 1908 indeed, the 16,000 long tons (16,257 t) limit imposed on capital ships by the United States Congress was waived, allowing new designs to be built (although still with a budget capped to
6 million USD). The Bureau of Construction and Repair undergone a serie of modifications and by 1909, the ships were the first in US naval history to exceed 20,000 long tons (20,321 t). Outside a length allowing an extra pair of 12 in cannons (305 mm), the Delawares reintroduced a full-fledged medium-caliber weapon for anti-torpedo boat defense, another critic of the previous design.


Blueprint of the class

This secondary artillery however was of 5-inch (127 mm), less than 152 to 160 mm adopted by European navies, but the guns were faster, and will imposed themselves as a standard throughout the XXth century. The Delawares were also capable of 21 kn (24 mph; 39 km/h) versus 18.5 kn (21 mph; 34 km/h) on the previous ships, more in line with modern dreadnoughts. At first drawn with classical simple masts, the latter were converted to their completion in cranes for lifeboats. Their “corbel” type masts were a recurring feature of American BBs until the 1940s.

Protection

This was probably the less revolutionary of the three aspects: The armored belt ranged was 9 to 11 in (229 to 279 mm) thick, on the more important areas of the ship (from A turret to Z turret). Barbettes had between 8 and 10 in (203 and 254 mm) of armor. Main gun turrets base and “well” was armored with 4 to 10 in (102 and 254 mm). The front and rear sections of the main barbette received thinner armor to save weight. The gun turrets were 12 in (305 mm) thick, conning tower 11.5 in (292 mm) thick but deck armor was quite thin at 1.5 in (38 mm) but 2 in (51 mm) over the engines and ammo magazines. Indeed engagements were thought to be less than 10,000 yd (9,144 m). At such distances, high angles deck impacts would be rare.


USS North Dakota firing a broadside

Propulsion

Long story short, North Dakota was fitted with steam turbines, whereas Delaware retained triple-expansion engines. US turbines the did not bring frank advantages in output or speed over triple-expansion (TE) systems. They were also much less fuel-efficient, a crucial flaw for the Pacific, as the US lacked an extended network of coaling stations, unlike Great Britain.

Armament

They also received two additional 305 mm pieces (one more turret), bringing the total to 10 as the British HMS Dreadnought, but crucially, all the turrets were in the centerline, allowing a better broadside, with all guns to bear, but at the cost of chase and retreat firepower. These 12-inch/45 caliber Mark 5 guns had a rate of fire of 2-3 rpm, with 870 lb (395 kg) shells, of AP or HE types declared obsolete by 1915. Propellant charge was 310 lb (141 kg) in silk bags, muzzle velocity was 2,700 ft/s (823 m/s).

Like the previous class, the front artillery was mounted fore in a superfiring pair, while the rear turrets were disposed in such a way that one in-between was sacrificed and cannot fire in retreat but in high angle only, and with care, its blast knocking the Z turret each time. This center-line disposition was optimized for broadsides. There was another design challenge imposed by the weight of the artillery, 437 long tons (444 t) per turret, imposing some hull stress management. This was partly solved by deepening the hull.


5in (127 mm) casemate

However, they were also critics about their 5-inch/50 caliber Mark 6 barbettes, far too low, putting the efficiency of these secondary guns at the mercy of gales. In fact they were extremely wet at all times.
These guns however compensated by a rate of fire of 6 to 8 rounds per minute. Three types of ammo were in store: “light” AP shell of 50 lb, “heavy” AP round of 60 lb and the common Mark 15 shell of 50 lb. The latter had a muzzle velocity of 3,000 ft/s (914 m/s), vs 2,700 ft/s (823 m/s) for the heavy AP ones. The Bliss-Leavitt 21-inch Mark 3 Model 1 torpedo were installed underwater on both sides, and had an explosive charge of 210 lb (95 kg) of TNT, and could achieve a range of 9,000 yd (8,230 m) at 27 kn (31 mph; 50 km/h).

Later in wartime, an anti-aircraft artillery was installed, two 3-inch/50 caliber anti-aircraft (AA) guns in Mark 11 mounts in 1917. Maximum ceiling 30,400 ft (9,266 m) at 85 degrees.

The Delaware class in action

Prior to the war, the Delaware shown it could run at full speed for 24h, and endure the stress of it during trials, the first American warship to do so. She spend her career in fleet exercises with the US Atlantic Fleet, and did trips to Europe, South America, the Caribbeans, taking part in the Second battle of Vera Cruz in April–May 1914. The North Dakota also served with the Atlantic Fleet and her sister-ship, paid a visit to Europe in 1910, took part in the invasion of Vera Cruz in 1914.


USS North Dakota in the Panama canal

USS Delaware and North Dakota in 1914-18

Both ships served in the Atlantic during the war, however the North Dakota remained stateside, barely leaving the coastal waters. This was due probably to its somewhat unreliable turbines and ordered by rear admiral Hugh Rodman, the naval commander of the American expeditionary force. She started in 1917 a new mission of training gunners and naval engineers. When the war started for the US in April 1917, USS Delaware trained on the eastern coast before eventually join the US Navy’s Battleship Division Nine deployed in Europe, under the command of Rear Admiral Hugh Rodman. She then was assigned on 7 December to the 6th Battle Squadron of the Grand Fleet. She eventually returned to the US on July 1918.

Postwar

The Delaware made only two more cruises, in 1922 and 1923 (a long trio to Europe, and up to Gibraltar) before returning and being decommissioned and disarmed in Boston Navy Yard in November. North Dakota made a second trip to Europe, mostly in the Mediterranean Sea. She was tasked with the return of the remains of the Italian ambassador, Vincenzo Macchi di Cellere (died 20 October 1919 in Washington, DC). She then returned and participated in aerial bombing demonstrations off the Virginia Capes in 1921. In 1923, she made a third trip to Europe with midshipmen from the Naval Academy aboard, stopping in Spain, Scotland, and Scandinavia. But like her sistership she was relegated to the surplus naval forces targeted by the Washington Naval Treaty. Unlike the Delaware after being disarmed in 1923 she was converted into a target ship, redesignated as “unclassified”, and used as a target until 1931, scrapped afterwards.


USS North Dakota in Malta

Specifications
-Displacement: 20 400t, 22 060t FL
-Dimensions: 158,20 m x26 m x 8,3 m ()
-Propulsion: 12 Babcock et Wilcox boilers, 2 screws, 2 Curtis turbines, 25 000 hp, 21 knots.
-Armour: Belt, barbettes 250 mm, turrets, conning tower 305 mm.
-Armement: 10 x 12in (305 mm) (5×2), 14 x 5in (127 mm), 2 TT (side, sub) 21 (533 mm).
-Crew: 880 sailors and officers

Gallery


Profile of the Delaware in 1914


North Dakota before the war


USS Delaware rear battery


USS Delaware in 1920


USS Delaware in full speed trials after completion. She sustained 24h at 21 knots without any problems with its TE engines.

Soviet Riverine Gunboats and Monitors

USSR

An introduction to Soviet Riverine Gunboats

The immensity of the Russian territory and the vast and deep rivers which traversed its land from the Urals or the Caucasian chains played the same role as the Mississippi and its tributaries during the American civil war: Convoying troops and carrying out missions Fire support and surveillance. As a result, the USSR was the country that built the most units of its kind during the war. They proved valuable to the Wehrmacht, not being held back by the natural conditions of the bad roads during the break-up. The most common lightweight models were equipped with heavy tank turrets and machine guns, and were armored, and these units sometimes faced German panzers. Others served as fire support ships during the great offensives, notably thanks to their “Stalin organs”.

Shkval class Gunboats (1910)

These monitors dating from before the Great War had been so well realized that they were still in proper condition after the Civil War. The Lenin, Sverdlov, Trockiy and 4 other units were re-started in 1927-34 and then in service with the fleet: Dalchevostolchnoi Komsomolec, Dzerzhinskiy *, Kirov * and Sun Yat-Sen . All survived the conflict. Some served on the Amur, on the Chinese border.
* double or triple denomination: Also name of a coastguard, and a Kirov class cruiser.
Specs: 950 tonnes standard, Dimensions 65 m x 8.2m x 0.82 m
Propusion: 2 screws, 2 diesels, 2200 hp.
Top speed: 14 knots
Armament : 5 x 130 mm, 1 x 45 mm, 6 12,7 mm AA Heavy MGs
Crew: 98


Krasnoye Znamya

Second class Gunboats (1910-1925)

These old gunboats were recovered in more or less good condition in the mid-twenties and kept in service. In 1941, the fleet included the Pionyer (formerly Korshun, coastguard of 1903), and the Khraby, another coast guard that was modernized in 1944 to take on the new configuration above and named Krasnoye Znamya. The Pionyer was lost in 1941 (mines?), And the Znamya survived the war and still served in the sixties…


Krasnoye Znamya

Specs: 1 020 t. standard
Dimensions: 66 m x 9,9 m x 2,30 m
Propulsion: 2 screws, 2 diesels, 3200 hp.
Top speed: 16 knots
Armour: 20 mm+
Armament (1941): 5 canons x 130 mm, 8 x 37 mm AA
Crew: 120


BK-213, 322 in night action


2 views of the Udarnyi class

Udarnyi class riverine monitors (1932)

Built in Kiev, these two powerful sister-ship monitors of 1932 served on the Dnieper. It was there that the Udarnyi was sunk in 1941 by the Luftwaffe.
Specs: 385 t. standard
Dimensions: 51 m x 8,2 m x 0,82 m
Propulsion: 2 screws, 2 diesels, 1600 hp.
Top speed: 13 knots
Armour: Up to 35 mm?
Armament: 2 x 130 mm, 4 x 45 mm, 6 12,7 mm HMG AA
Crew: 70

Flyagin riverine Monitors
Flyagin riverine Monitor, two views

Zheleznyakov class riverine monitors (1934)

These 6 monitors were built in 1934-39 in Kiev to serve on the Dnieper. They were armored, and were all lost in combat except the Zheleznyakov, preserved and showcased today in Kiev.

Specs: 263 t. standard
Dimensions: 48 m x 7,6 m x 0,75 m
Propulsion: 2 screws, 2 diesels, 300 hp.
Top speed: 7,6 knots
Armour: Unknown
Armament: 2 x 102 mm, 4 x 45 mm, 4 x 12,7 mm HMG AA
Crew: 70

Khasan class monitors - 2 views

Khasan class monitors

Khasan class riverine monitors (1943)

These two monitors were built in 1943-45 in Kiev to serve on the Dnieper. They were clearly inspired by the Udarniy, and were joined by a third unit in 1946.
Specs: 1 900 t. standard
Dimensions : 75 m x 11 m x 0,90 m
Propusion: 2 screws, 2 diesels, 1000 hp.
Top speed: 8 knots
Armour: Unknown
Armament: 4 x 130 mm, 8 x 45 mm, 6 x 12,7 mm HMG AA
Crew: 250

World War Two Dniepr Flotilla

First constituted in June 1931, a small flotilla was disbanded in June 1940, and the ships realocated to the new Danube Flotilla created with Soviet occupation of Bessarabia and Northern Bukovina and the Pinsk Flotilla. A new Dnieper Flotilla was also constituted from ships of the Volga Flotilla in September 1943.

By the time of spring 1944 offensive, the Dnieper flotilla consisted of no less than 140 boats and ships, included, in out case, 16 armored gunboats. Commander was Rear Admiral Vissarion Grigoriev. The flotilla operated on the Dnieper River and tributaries, like the Berezin, Pripyat River, Vistula and tributary the Western Bug, Oder and Spree. The Dnieper ended into the Black Sea, while the Bug, Vistula, Oder, and Spree drain into the Baltic sea. Existing canals provided links between these.

BK type gunboat preserved as a monument at Pinsk.
BK type gunboat preserved as a monument at Pinsk.

The Flotilla’s contributed to the protect the flanks of advancing Soviet troops in Ukraine, Belarus, and Poland. Outside of logistic support, it also performed amphibious landings (Pinsk, Zdudichi, Petrikovsky, Borkinsky, and Doroshevichinsky). Units also fought on the Oder and Spree and throughout the battle of Berlin, bringing close support. The Dnieper Flotilla was disbanded afterwards.

The BK armored gunboats were certainly the most common and useful. In 1941, no less than 85 of these were in service, 68 under construction, 110 on order. They paid a heavy price in operations, as about 90 were lost. Outside a T34/76 tank turret (early types had T-28 and T-35 turrets) as main armament, they also had lighter 7.62 PKT in T-28/35/26 light secondary turrets. The BK-1124 had two main turrets and BK-1125 one, with a 12.7mm DshK machine gun AA and two PKT 7.6mm machine guns, sometimes a Katiusha type rocker launcher. There were several combination known, and many vessels were camouflaged.

Preserved BK-1125 at Kiev, showing its T-34/85 turret and twin 12.7 mm above the bridge.
Preserved BK-1125 at Kiev, showing its T-34/85 turret and twin 12.7 mm above the bridge.

Zheleznyakov class river monitor, of which five were built at Kiev also served with the Dnieper Flotilla. Outside a twin 4-inch (100 mm) main armament, they also had 2 x 2 45 mm (1.7 in) guns, and four PKT standard machine guns. The Flotilla was awarded the Order of the Red Banner in 1944, and the Order of Ushakov, First Class, in 1945. Some subunits were made Guards or received honorary battle names (Pinsk, Bobruisk, Luninets, Berlin) as well as Three thousand soldiers and sailors has been awarded, twenty of which were made Hero of the Soviet Union.

Nowadays a monument at Pinsk (BK serie ship) stands to commemorate the flotilla but others are showcased in Kiev, Mariupol, Blagoveshchensk, even Khabarovsk (far east).


BK-1125 closeup, T-34/76 turret


Camouflaged BK-1125, rear platform, 12.7 mm DSHK Heavy Machine Gun. (cmchant.com)

The BKA 1124 class (1934)

Constructed in mass since 1935, these units relied on the numerous armored gunboats deployed successfully during the civil war as well as the armored trains and on the prototypes N and K. Their peculiarity was to use turrets of Tanks, and to have the corresponding shielding. The former had heavy tank turrets T-28 and T-35, then in 1939, T-34, the standard tank of the Soviet army. About 60 were in service during the German invasion, and more than 150 were built, some equipped with rocket launchers ROFS-82 (Katiucha) fire support.

BKA-1125 type profiles
BKA-1125 type profiles

Specs:
Displacement: 42 tonnes standard
Dimensions: 25 m x 3,80 m x 0,80 m
Propulsion: 2 screws, 2 gasoline engines, 1600 hp.
Top speed: 28 knots
Armour: 15 to 50 mm
Armament: 2 x 76 mm, 2 12,7 mm HMG AA
Crew: 17

The BKA 1125 class (1938)

These armored gunboats, built in 1938, were derived from the 1124 BKA, they were smaller and had only one tank turret, and were always propelled by two gasoline engines. Approximately 20 were in service before the German invasion, with the others taking office during the years 1942 to 1944. A total of more than 150 since the total number of BKAs represents at least 270 units. In 1943, their turrets of T34 were those of model T34 / 85, with longer range. Some had rocket launchers. About 90 gunboats 1124 and 1225 will be cast in combat.

Specs:
Displacement: 29 tonnes standard
Dimensions: 22.6 m x 3,50 m x 0,50 m
Propulsion: 2 screws, 2 gasoline engines, 720 hp.
Top speed: 28 knots
Armour: 12 to 50 mm
Armament: 1 x 76 mm, 1 x 12,7 mm HMG, 2 x 7.62 mm LMG AA
Crew: 10

MBK class (1943)

These twenty large units, project 161, were intended to operate in the Baltic Sea coast, enlarged versions of the 1124 BKA. The prototype was built in Leningrad 1941-43 and the others in 1944-45. The latter used guns of 100 mm rather than those of 85 mm. These boats derived from pre-war project 138, originally adapted for quick building in Leningrad, with simplified rectilinear hull form, lend-lease engines and widely available T-34 tank turrets. The BKA were better suited to estuarine and coastal operations and the design was essentially an enlarged version of the Type 1124, for use on the shallow waters of the Baltic. The previous type 1124/1125 BKA carried T-34/76 tank turrets, but the BKM was given the much more potente T-34/85 turrets armed with the high-velocity (3.35-in) ZiS-53 gun, and later eventually a 100-mm (3.94-in) gun. Recoil problems were certainly less acute for a large ship than for the suspensions of a tank.

The BKA received a substantial protection, 50 mm (2 inches) plates on either sides, and the conning tower, which made them able to compete with German tanks, at least the most common models. In addition to their main 3.35- or 3.94-in gun, they received one 37-mm L/67 AA QF gun and four 12.7-mm (0.5-in) heavy machine guns for anti-aircraft defense.Initially the BKA were given 2 x 82mm mortars, but 45 mm guns were given instead. Two models were apparently built, the early one showing a prominent bow-guard and different armament disposition.

They were all built at 194 Yd, Leningrad, the first one, БК-501, being laid down on 10/1942, launched in 11/4/1943 and completed in 9/1943, whereas the last of 20, БК-520 was started in June 1944, launched in September and completed in October 1944. Surviving MBKs in 1946-1949 were classified as small gunboats.


BK-506, date unknown

Ship protection: Belt had 52-50 mm thickness abreast citadel and was closed by 14 mm fore and 48-30 mm aft bulkheads, it was connected with 35-30 mm deck. Ship ends outside citadel were protected by 18-14 mm belt and 18-12 mm deck.


Profile of the MBK-161, early type.

Specs:
Displacement: 151 tonnes standard, 158 fully load.
Dimensions : 36.2 m x 5.50 m x 1,28 m
Propulsion: 2 screws, 2 Packard petrol engines 2400 hp.
Endurance: 450 nm @10 knots
Top speed: 13 to 18 knots
Armour: Belt: 50 mm – 25 mm, deck: 30 – 15 mm, turrets up to 45 mm, CT: 8 mm
Armament: 2 x 76/40 F-34 85 mm, 1 x 37 mm 45/65 21KM or 37/63 70K, 4 x 12,7/79 mm HMG AA
Crew: 42


MBK 186, late type

MBK gunboats in action

The Battle of Nerva Island (20 june 1944) took place when Germans attacked the Gulf of Finland, sending two large Elbing-class torpedo boat T-30 and T-31. “Operation Drosselfang” had the purposed of “cleaning” light units around Nerva Island. On the area, soviet forces possessed 14 motor torpedo boats, 10 sub chasers (of MO-4 class) and 4 small gunboats. The submarine chaser MO-106 was lightly damaged as well as two small gunboats MBK-503 and MBK-505. At that point, the Soviet counter attacked with the TK-53, TK-63 and TK-153, followed by TK-101 and TK-103, all lightly damaged. Eventually a third attack succeeded with a pincer movement (one sunk, one forced to retreat).
The BK-504 was sunk on 4/7/1944, as the BK-509, and the БК-514 by German mines. Surviving ships were renamed on 11/1946 МКЛ-1 to 38, and reverted to their original name on 2/1949. They were eventually all striken from 10/1949 to 3/1958.


BK-1124 type

References:
soviet-empire.com
cmchant.com
forum.axishistory.com
navypedia.org
wio.ru
BK1124 model
Soviet ww2 monitors

Type II Class submarine

Nazi Germany (1935)
50 Submarines Types IIa, IIb, IIc, IId

Beach Patrol

In 1930, the false Dutch company NV Ingenieurskantoor voor Scheepsbouw den Haag (set up in the Netherlands to develop submarines for Germany after WW1) set out to design a new class of submarine as a means of coastal patrol and defense. This submarine was bought by the Finnish government and was called the CV-707 Vesikko. This became the basis for development of a new class of submarine for the German Kriegsmarine.


Finnish Vesikko, CV-707 prototype submarine in service and camouflage livery during the war.

In 1933, NV Ingenieurskantoor voor Scheepsbouw den Haag designed a new and improved CV-707 that would be built for the German navy at the Kiel shipyard. This class became the Type IIA, with the U-1 being the first built. It’s primary roles were training of new crews and coastal defense.

Design

The Type IIA had a length of 134 feet, a beam of 13 feet, and a draft of 12 feet, meaning that the sub was small and could only operate in coastal waters. A conning tower was located in the center of the boat and housed the periscopes that the sub would use to see while underwater. A single anti-aircraft gun may be mounted here.

Displacement for the Type IIA was 250 tons surfaced and 298 tons submerged. A test depth of 150 meters could safely be reached, although captains of submarines would regularly take their subs deeper than the test depth. With a crew of up to 25 men, the Type II was cramped and uncomfortable, although proportionate as other submarines such as the American Gato Class were 3 times the size and had 3 times the crew.


Cutaway plans of the U Boat type II

Armament

Armament of most Type II submarines was 3 533mm torpedo tubes, all forward facing, with 5 torpedoes carried in total. In addition, 1-2 20mm anti-aircraft cannons were carried. No deck gun or heavy anti-aircraft was carried.
In addition to the underwater and surface weapons, small arms such as MP-40 submachine guns and P-38 handguns were carried for self defense and boarding.
Interestingly, all German submarine crews were also trained in land combat, so it can be assumed that the crews were at least somewhat skilled with their small arms.

Propulsion

German submarines, while having diesel and electric engines, were not true diesel-electrics. They used their louder diesel engines on the surface and their electric engines underwater.
Powering the Type II were 2 diesel engines and 2 electric motors allowing for up to 13 knots surfaced and 7 knots submerged.
Type IIA subs could travel 1,600 nmi at 8 knots while surfaced and 35 nmi at 4 knots while submerged.
Type IID subs could travel 5,650 nmi at 8 knots while surfaced and 56 nmi at 4 knots while submerged.

Active Service

The first Type II submarines were completed in 1934, although most of the world did not know of their existence until 1935, when Germany and Great Britain signed a treaty allowing Germany to match England’s submarine fleet.

Type II submarines would be used in the beginning years of the war as a training and coastal patrol boat until a shortage of U-Boats in 1942 and 1943 would see them supplementing the larger Type VII class in anti-ship roles.
In total, there were at least 4 combat flotillas that operated the Type II. These included the 1st, 3rd, 5th, and 30th Flotillas. Most of these operated out of Kiel, with one notable exception.

Starting in 1942 with the formation of the 30th U-Boat Flotilla, Type IIBs would be used in the Black Sea, attacking Russian shipping and reinforcements making their way to the front line. The Flotilla was disbanded in 1944 after the destruction of all remaining U-Boats.
At the start of hostilities with France and England, the Type II was more used for coastal patrol and training, but as the war dragged on, it saw more combat in the English Channel. Eventually, the Type II was to be replaced by the Type XXIII “Elektroboot”, although the Type II was never fully replaced in the Kriegsmarine.

Sources:
https://en.m.wikipedia.org/wiki/German_Type_II_submarine
http://www.kagero.pl/index.php?option=com_content&view=article&id=194:the-type-ii-u-boat&catid=96:navy&Itemid=686
http://www.uboataces.com/uboat-type-ii.shtml

Gallery


U-Boat Type IIa waterline profile (1/400)


U-Boat Type IIc full profile for comparison


U1 in service with the Kriegsmarine before the war


U9, of the following IIb class.


The Vesikko preserved at Susisaari island in Suomenlinna near Helsinki as of today. It has been restored and opened as a museum in 1973.