Skorpionen class Monitor (1867)

Norwegian Monitors (1867-1908): Skorpionen, Mjølner, Thrudvang

The Skorpionen-class were three monitors of the Royal Norwegian Navy built from 1866 to 1869. HNoMS Skorpionen, Mjølner and Thrudvang were active until scrapped in 1908. The slightly later Thor can be seen as an improved Skorpionen-class monitor, but the concept, inspire by the US Civil war, remained valid for the fjords defence system of Norway, for decades, way past the technology of their main guns. This is the start of a new cycle on the Norwegian Navy.

Development

The Skorpionen class were among the first monitors in service in Scandinavia at large, aside those of Sweden, and later, Denmark or the Netherlands. The type of ship was well known since 1862 and the first famous fight of USS Monitor against CSS Virginia in the American Civil War. The Union from the continued to built monitors, while the Confederates, lacking industrial capabilities, stuck to simpler casemate ironclads. They had been designed for riverine operations, so calm waters, but proved capable of shore operations as well as shown by the fight at Hampton roads.

In 1865, the Norwegian Navy was seen as a semi-independent force, attached to the Swedish Kingdom. Its own parliament could decide the construction of new ships tailored to its needs, and its navy only counted the 34-gun 1856 Frigate St. Olaf, the 14-gun 1855 Corvette Nornen and the 6-gun 1856 corvette Ellida, plus four smaller screw warships, from to 2 to 20 guns each, two 2-gun side wheel steamer. This steam fleet was completed by a 40 and 44 guns sailing frigates and a 16 and 10 guns sailing corvettes. Norway, in sometimes difficult relations with the Kingdom of Sweden, was a much poorer country, and its fleet was clearly ageing with a small navy that was spread thin between Fjords, leading to its most important cities. In case of a maritime invasion by a major naval power, it would have struggled in any of these.

So the Norwegian naval staff followed the American Civil War with great interest, seeing the monitors as “the ultimate deterrence”, well-suited to the calm waters of its fjords and not impaired by their slow speed, negated by the confines of geography. Impervious to gunfire and with their powerful guns in turrets, they could face with confidence any large conventional frigate or corvette. They looked as an ideal deterrence. Three monitors could on paper defend the three most important waterways, notably to the capital Oslo, Bergen and Stavanger. However in 1865 with the American Civil War still in full swing it was out of question of ordering these ships from US yards, as they were still badly needed, but John Ericsson (Swedish born) was contacted to deliver plans for the Norwegian ships, as he had done for the Swedes, once they had been voted at the Storting (parliament).

Indeed, Sweden itself embarked on the concept, with its much deeper pocket, as its own geography also was favourable to the type. In fact they had been faster than the Norwegians, and ordered earlier in 1864, with the first launched at Nörköping in 1965, named after the country’s own prodigal son, “HMS John Ericsson”, followed by HMS Thordon in 1866 and Tirfin in 1867. Given somewhat tense relations with Sweden, Norway did not want to miss the train, and that forced the hand of its own parliament. It’s possible also both Kingdoms, under the same ruler, embraced a common naval policy concerning its defence, and it could have led to built monitors to defence both coasts (the dragon’s head). Sweden would order another monitor, launched on 1871, HMS Loke (Loki) to which the Norwegians “answered” with Thor built in Horten, launched in 1872. Then, both countries stopped this fad and went for more seaworthy cost defence ships, after decades in the case of Norway, with the Haarfarge class of 1897 (Built in Britain).

Of the three Skorpionen class, the first and last were built at Horten Shipyard in Norway and one in Nörköping, Sweden, HNoMS Mjølner. HNoMS Thrudvang was the last monitor of this first series. By combining a fleet of eight monitors in 1873, Sweden and Norway had one of the largest force of this type in Europe, albeit their own relations degraded over representation and sovereignty questions (see below). But the context was far more favourable in 1865 to a common naval defence policy involving monitors. It is likely that their construction was pushed through by right-wing politicians seeing the monitors as a contribution to the common union defence. Karljohansvern, at Horten, where the main Norwegian military naval yard and arsenal were located, was the main base for the Royal Norwegian Navy from 1850 to 1963.

Design of the class

Hull and general design

The Skorpionen class were not that different from the Swedish, slightly earlier Ericsson class. They were typical shallow-drought low freeboard vessels with a single twin-gun turret forward, machinery and funnel at the center and single mast. They were about the same size and tonnage at 1450 tonnes average, c60 meters long. To be more precise the Norwegian ships were larger, at 1,490 long tons (1,514 t) versus 1476 tonnes for the Swedish ones, albeit the lead ship was declared to have a displacement of 1425 tonnes, probably Conways giving its standard displacement (light) figure. They carried 85 officers and ratings.

The Skorpionen class were also longer and larger than the Swedish Ericsson class, at 62.33 meters (204 ft 6 in) whereas Skorpionen initially was short and close to the Swedish ships at 60.96 meters or 200 ft, for a beam of 13.68 (Skorpionen) or 13.87 meters (The other two) (44 ft 11 in) and a draft that varied again from 3.35 meters for Skorpionen (11 ft) to 3.50 meters (11 ft 6 in). The design was nearly identical as the Ericsson class, turret forward, machinery amidship, with a tall funnel aft, and like later US monitors, there was a main observation post at the center of the turret’s roof, while a “flying bridge” started at the turret and ended at the funnel. There was another platform built around the latter and four boats under davits, two amidship, two aft. There was no main mast, but three short poles, one forward, one aft and one signal pole above the spotting cab on top of the turret. The hull low freeboard met a slightly sloped deck (turtleback) for rapid water flow.

Powerplant

There is little information about its exact nature or origin. It was described as a Steam engine, in some sources decribed as a HRCR (Horizontal Reciprocating with Return Rod) fed by four boilers. But in others as a vibrating lever engine (VLE). In all cases it was rated for 450 ihp (336 kW) for the last two ships, for a top speed of 8 knots (15 km/h; 9.2 mph). Skorpionen differed by a less powerful steam engine rated for 330 hp and making for a top speed of 6 knots. They carried between 130 and 140 tonnes of coal, but the radius of action is unknown, sometimes described as 800 to 1000 nm at 5 knots.

Protection

It was made of laminated iron, but mixing Steel and wrought iron armor. It is unsure if Horten was able to provide the laminated plates, or if they were imported, albeit Norway was reputed for its rich iron ore extraction sites, local steel industry was still limited due to the underinvestment. Most iron ore was exported, notably to Britain, Sweden and Germany. This armour was a 12-inch Turret (300 mm), a 5-inches (130 mm) Belt and a deck that was also 5-inches thick for good measure so between that and their lopw freeboard they were considered unsinkable by conventional warships. For technical details see USS Monitor.

Armament

The turret housed a pair of rifled, breech-loading (RML) 10.5in (267 mm) Armstrong guns N°1. They were also used on the 1874-78 Vale Class 250ton gunboats – Vale, Brage, Nor, Uller and Vidar and after the ships were modernized, recycled in fortifications and still active in 1940. These were 13 calibre 18.2 tonnes (19.7t barrel and mount) guns. No more data on these.
The ships were modernized, Skorpionen in 1884 and 1897, armed then with a pair of 37 mm (1.46 in) Hotchkiss quick-firing gun on the upper platform to deal with torpedo boats, as well as two 9-pdr guns under shields amidship, and the heavy guns were removed and replaced by two 4.7 inches Armstrong QF guns under shields, one mounted above the turret forward now fixed in place, and another aft (see modifications in their career below).

Unknown, c800 nm for 130-140t coal

For context: Swedish-Norwegian Relations 1860-90

Relations between Sweden and Norway between 1860 and 1890 were shaped by their political union, growing Norwegian nationalism, disputes over sovereignty and foreign policy. This was the middle phase of the Swedish–Norwegian Union, moving from cooperation toward increasing tension eventually leading to the peaceful dissolution in 1905. After the Treaty of Kiel, Norway was forced into a union with Sweden but kept its own constitution dating back from 1814, its own parliament (Storting), laws, and institutions but the countries shared a monarch, joint foreign policy, diplomatic representation controlled largely from Stockholm, and also their collective defence.

By 1860, the union had existed nearly 50 years but remained politically unequal. Relations were relatively stable with Swedish elites seeing the union as strategic security albeit Norwegian politicians increasingly demanded greater autonomy. The key tension point was that foreign affairs were run from Sweden and this led to the rise of Norwegian Nationalism for the 1860s–1870s decade while Norway experienced economic growth in shipping and trade, cultural nationalism and expansion of democratic politics. The Storting became more assertive and sought ministerial accountability, reduced royal authority, and milited for equality within the union, clashing with Swedish political traditions.

This led to the “Stattholder” Question, a major dispute involving the stattholder (viceroy in Norway) as Norway wanted the office abolished, leading to a Constitutional Crisis from the 1870s to 1884 with the Norwegian liberals lobbying strongly for reforms repeatedly by the King of Sweden. Long story short, Norway from 1884 became highly parliamentary and democratic, creating an imbalance with a more conservative and Royalist Sweden. It mattered in the 1880s as Norway rapidly developed on of the world’s largest shipping industries.

Career of the Skorpionen class

HNoMS Skorpionen (“Scorpion”) was the lead ship of her class, laid down in January 1865, launched in 1866 at Horten Navy Yard, Nörköping and completed in 1867. She was to be followed by Mjølner and Thrudvang, improved and larger, two knots faster given their more powerful engine, from 330 to 450 shp engine. Thus, Skorpionen ended as the slowest of the three at 6 knots versus 8 knots for her sisters. Global construction cost had been estimated to 286 000 Speciedaler. Little is known about her career. In 1867 as completed she had these original 10.5 inches or locally 27 cm main guns, L/12.5 calibre RML. The barrel alone weight 18.5 tons, and they were mounted each on a sled with an iron frame and recoil brake. They had limited elevation (unknown).
In some sources, this was reinforced by a 76.4mm Rifled Muzzle-loader aft.

In 1885 she was upgraded with a 10-barreled 12.17mm Winborg & Palmkrantz machine-gun. In 1897 she was completely rebuilt and modernized. Her old 267mm/13 main guns were removed, the turret fixed in place, plated over, central spotting post removed. Over it was mounted a twin 120mm or 4.7 inches 44 calibre Armstrong Y gun under shield, aft on deck were located two shielded 65mm/50 Hotchkiss guns and on top of the new superstructure that went from the turret to the funnel were located on side wings a 37mm/40 Hotchkiss gun on either side. The 65 mm are also described as Cockerill cannons in other sources, placed on the superstructure, 43 calibre, semi auto, with a Nordenfelt’s screw mechanism and protected by a 20mm thick light curved shield of nickel steel. The two 2-pdr Hotchkiss guns are L/20. Most sources describes them as placed on deck aft with 5mm special steel shields.

A new conning tower was built behind the turret, tall enough to see above the main guns. There was no proper navigation bridge as the CT played this role, albeit quite cramped. It was semi-open, with a perispheric opening topped by a mushroom style armoured dome. Thickness is unknown. A signal mas was located immediately aft of it and another aft of the structure. Displacement in 1898 jumped to 1,524 tonnes. Skorpionen remained part of Norwegian defence until placed in the Outer Oslofjord during the high tension period of the Norwegian-Swedish disunion. She was decommissioned afterwards on 16 October 1905 and scrapped in 1908, sold to Stavanger Skibs-Ophuggings CO A/S.

“Mjølner” (Thor’s mythological hammer) was built not at Horten, but at the Nörköping Motala shipyard in Sweden, due to reasons of capacity. She laid down in 1967 and built on an iron frame, with which the yard gained experience from earlier steam gunboats, then wrapped with wrought iron hulls. She was launched in January 1868 but completed at an unknown date, probably still the same year. Mjølner received the most attention outside military circles when she ran aground on an underwater reef off Kragerø, in her maiden trip back in 1869 and could not be refloated for over a week and then with the help of tuges and other steamers, pulled off. The underwater reef was renamed on the maps later the “Monitorbåen”.

The new Armstrong 26.7cm rifled cannons were procured before she was completed, but were somewhat criticized. These guns stood on rails and were manually cranked to be loaded inside the turret, elevated and the whole turret traversed. The gun crew had to put quite some effort at 20 tons apiece and their full load ammunition weighted 160 kg, lifted by winch from below. Like her sister she is confirmed to have an extra 3-inches of 76mm cannon “boat gunner” gun, that could be dismounted and placed on the onboard steam sloop for landing party short support.

Mjolnir, like the other monitors in her class saw practice cruises alone or in pairs together with torpedo boats or gunboats. They were always short affairs in domestic coastal waters, spring and summer, but sometimes she was detached to visit Swedish or Danish ports. In 1872 the three Norwegian Monitors were exceptionally united for a common exercises with the three Swedish monitors. Both unit commanders and royals went onboard for mutual inspections and witnessing gunnery practice. In stormy weather, all hatches on deck had to be sealed firmly essentially trapping the men inside, and the artificial ventilation produced such a strong draft that candles had to be covered with gas canisters. The engine room could reach as much as 70 degrees Celsius.

In 1897, both Mjolnir and Thrudvang were taken in hand for a complete modernization and reconstrtuction aloneg the lines of her sister Skorpionen (see above). Both lost their 267mm/13 RML for the addition of a twin 4.7-in or 120mm/44 (locally called 12.4 cm guns) Armstrong Y guns, two 65mm/50 Hotchkiss or Nordenfelt/Palmcranz guns, and two 2-pdr or 37mm/40 Hotchkiss guns, most likely placed on deck aft. Mjolnir was relocated at Melomsvik outside Tønsberg. During the mobilization of 1905, she was fully equipped and made ready for action. Skorpionen and Mjølner were sent to defend Oscarsborg. She later took part in the celebrations in Kristiania in October and returned to Horten and decommissioned.

HNoMS Thrudvang was laid down after her sister Skopionen was launched, in 1867, named after Þrúðvangr – the realm of the Norse god Thor, and launched herself on May 3, 1869. She was commissioned later in 1869. Like her sisters, her detailed operations and logs are unknown. She had a shakedown and initial training without issues, and took part in many cruises, like her sister Mjolnir in local waters, and in Sweden and Denmark.

In 1897, like her two sisters, Thrudvang was taken in hands for a complete modernization completed in 1899. In her new configuration (see above) she had a new structure and new armament, constisting of a twin 4.7 inches/44 Armstrong Y on top of her turret and two 65mm/50 Hotchkiss guns as well as two 37mm/40 Hotchkiss guns to defend against torpedo boats.

Thor (the new Norwegian monitor of the 1870s) and Thrudvang remained active afterwards until the change of centenry. Both vessels were still actvice and in 1916-17 took part in neutrality protection patrols around main Norwegian base. Postwar, Thrudvang was sold to Stavanger for scrapping. Meanwhile, Thor was lost under tow on March 1919, drifted aground and sank at Hoflø.

Read More/Src

Books

Conway’s all the world’s fighting ships, 1860-1905. Mayflower Books, now NIP.
Directory of the world’s capital ships. Hippocrene Books. 1984.

Links

skorpionen navypedia
Mjølner sub-class navypedia
forum.warthunder.com
nelsonlambert.blogspot.com
Erick Navas Skorpionen late 1890s colorized src
Skorpionen Modernized 1897+, photo source. digitalmuseum.no

Model Kits

None found

3D

None found