Aetna class ironclad floating battery
Encyclopedia
The Aetna-class ironclad floating batteries were built during the Crimean War
for the attack of Russian coastal fortifications.
Britain and France each laid down five of these coastal attack vessels in 1854. The French used three of their batteries in 1855 against the defences at Kinburn
on the Black Sea
, where they were effective against Russian shore defences. The British planned to use theirs in the Baltic Sea
against Kronstadt
in 1856, and were influential in causing the Russians to sue for peace. The development of such iron-armoured batteries was step towards the development of ironclad warship
s. "These armoured batteries were among the most revolutionary ships ever built and provided British and French designers with the germ of the battleship
."
One of the British batteries, the Trusty was used for trials in 1861 with a prototype rotating turret, based on Captain Cowper Phipps Coles
designs.
suggested using thick wrought iron plates instead. Trials at Vincennes showed that Lloyd's idea was more effective, so it was adopted.
Napoleon wanted ten floating batteries built in time for the 1855 campaign, but as French industry could only build five in time, France's British allies were asked to build the other five. Unfortunately the First Lord, Sir James Graham confused this concept with the unsuccessful iron-hulled frigates built in the late 1840s, and asked for further trials, so the British armoured batteries were not ordered until 4 October 1854.
. The French batteries carried 16 guns, but had 24 gun ports. The British Aetna class were also intended to carry 16 guns, but the first four completed only carried 14 guns to reduce draught to 8 in 8 in (2.64 m). The Admiralty design drawing showed them with 32 gunports. These ports were very large 34 in (0.8636 m) x 40 in (1 m).
The Aetna class had "wooden hulls, straight vertical sides and a flat bottom with a very bluff bow and stern. Their armour plates, nominally 4in [100mm] but in many cases rolled 0.25-0.5in under thickness, were locked together with tongue and groove joints." The iron armour was supported by 20 in (508 mm) thick oak sides. The wooden upper deck was 9 in (228.6 mm) thick. There were two conning towers protected by 5/8 in wrought iron plate.
In October 1858, experimental firing trials were undertaken against the Meteor and one of the follow-on class of iron-hulled armoured batteries, the Erebus. These demonstrated the importance of wooden backing for the armour, as the Meteor put up far better resistance than Erebus, where the frames were displaced by concussion.
On trials with a single 6 ft (1.8 m) diameter, 12 in 6 in (3.81 m) pitch screw, Meteor reached 5.7 knots (11.2 km/h) at 139 rpm with the safety valve set at 60 psi, and engine power was recorded as 530 ihp.
On her trials fitted as triple screw, the Meteor reached 5.25 knots (10.3 km/h) at 139 rpm. Engine power was recorded as 498 ihp. The two wing screws on this trial were 6 ft (1.8 m) diameter, 7 in 6 in (2.29 m) pitch.
Aetna (ii) had two-cylinder 27 in (0.6858 m) diameter 30 in (0.762 m) stroke horizontal single expansion engines of 200 nhp. Her boilers were salvaged from Aetna (i).
Note that whilst Admiralty records for Meteor, Thunder, Glatton and Trusty state that both the Mare and the Green yards were at Limehouse, other vessels built by Mare and by Green were built at Blackwall. It is possible that there is an error in the records, and they were really built at Blackwall.
Crimean War
The Crimean War was a conflict fought between the Russian Empire and an alliance of the French Empire, the British Empire, the Ottoman Empire, and the Kingdom of Sardinia. The war was part of a long-running contest between the major European powers for influence over territories of the declining...
for the attack of Russian coastal fortifications.
Britain and France each laid down five of these coastal attack vessels in 1854. The French used three of their batteries in 1855 against the defences at Kinburn
Battle of Kinburn (1855)
The Battle of Kinburn/Kil-Bouroun was a naval engagement during the final stage of the Crimean War. It took place on the tip of the Kinburn Peninsula on 17 October 1855...
on the Black Sea
Black Sea
The Black Sea is bounded by Europe, Anatolia and the Caucasus and is ultimately connected to the Atlantic Ocean via the Mediterranean and the Aegean seas and various straits. The Bosphorus strait connects it to the Sea of Marmara, and the strait of the Dardanelles connects that sea to the Aegean...
, where they were effective against Russian shore defences. The British planned to use theirs in the Baltic Sea
Baltic Sea
The Baltic Sea is a brackish mediterranean sea located in Northern Europe, from 53°N to 66°N latitude and from 20°E to 26°E longitude. It is bounded by the Scandinavian Peninsula, the mainland of Europe, and the Danish islands. It drains into the Kattegat by way of the Øresund, the Great Belt and...
against Kronstadt
Kronstadt
Kronstadt , also spelled Kronshtadt, Cronstadt |crown]]" and Stadt for "city"); is a municipal town in Kronshtadtsky District of the federal city of St. Petersburg, Russia, located on Kotlin Island, west of Saint Petersburg proper near the head of the Gulf of Finland. Population: It is also...
in 1856, and were influential in causing the Russians to sue for peace. The development of such iron-armoured batteries was step towards the development of ironclad warship
Ironclad warship
An ironclad was a steam-propelled warship in the early part of the second half of the 19th century, protected by iron or steel armor plates. The ironclad was developed as a result of the vulnerability of wooden warships to explosive or incendiary shells. The first ironclad battleship, La Gloire,...
s. "These armoured batteries were among the most revolutionary ships ever built and provided British and French designers with the germ of the battleship
Battleship
A battleship is a large armored warship with a main battery consisting of heavy caliber guns. Battleships were larger, better armed and armored than cruisers and destroyers. As the largest armed ships in a fleet, battleships were used to attain command of the sea and represented the apex of a...
."
One of the British batteries, the Trusty was used for trials in 1861 with a prototype rotating turret, based on Captain Cowper Phipps Coles
Cowper Phipps Coles
Captain Cowper Phipps Coles, C.B., R.N. , the son of the Reverend John Coles and his wife Mary Ann Goodhew Rogers, was an English naval Captain and inventor. Coles died when HMS Captain, an experimental warship built to his designs, sank with him onboard.-Naval career:He entered the Royal Navy at...
designs.
Genesis
Emperor Napoleon III initiated the design of armoured steam-powered batteries for the French Navy. The original idea was to protect the sides with boxes of cannon balls, but the British engineer Thomas LloydThomas Lloyd
Thomas Lloyd may refer to:* Sir Thomas Lloyd, 1st Baronet, Welsh politician* Thomas Lloyd , Welsh cleric and lexicographer* Thomas Lloyd , Lieutenant Governor of Pennsylvania, 1684–1688...
suggested using thick wrought iron plates instead. Trials at Vincennes showed that Lloyd's idea was more effective, so it was adopted.
Napoleon wanted ten floating batteries built in time for the 1855 campaign, but as French industry could only build five in time, France's British allies were asked to build the other five. Unfortunately the First Lord, Sir James Graham confused this concept with the unsuccessful iron-hulled frigates built in the late 1840s, and asked for further trials, so the British armoured batteries were not ordered until 4 October 1854.
Design
These vessels were copies of the French Dévastation-class batteriesDévastation class ironclad floating battery
The Dévastation class ironclad floating battery were built for the attack of Russian coastal fortifications during the Crimean War....
. The French batteries carried 16 guns, but had 24 gun ports. The British Aetna class were also intended to carry 16 guns, but the first four completed only carried 14 guns to reduce draught to 8 in 8 in (2.64 m). The Admiralty design drawing showed them with 32 gunports. These ports were very large 34 in (0.8636 m) x 40 in (1 m).
The Aetna class had "wooden hulls, straight vertical sides and a flat bottom with a very bluff bow and stern. Their armour plates, nominally 4in [100mm] but in many cases rolled 0.25-0.5in under thickness, were locked together with tongue and groove joints." The iron armour was supported by 20 in (508 mm) thick oak sides. The wooden upper deck was 9 in (228.6 mm) thick. There were two conning towers protected by 5/8 in wrought iron plate.
In October 1858, experimental firing trials were undertaken against the Meteor and one of the follow-on class of iron-hulled armoured batteries, the Erebus. These demonstrated the importance of wooden backing for the armour, as the Meteor put up far better resistance than Erebus, where the frames were displaced by concussion.
Machinery
The first four completed had two-cylinder 25.5 in (0.6477 m) diameter 24 in (0.6096 m) stroke horizontal single expansion engines of 150 nhp, which operated at 62 psi (427.5 kPa). Although they were completed as single screw vessels, the Meteor was altered to triple screw with wing-shafts; her trials with triple screw were 12 days after her trials with single screw. The most likely method of driving the wing shafts was a belt arrangement, which was common practice at the time. It is unclear whether any of the others were also altered to triple-screw.On trials with a single 6 ft (1.8 m) diameter, 12 in 6 in (3.81 m) pitch screw, Meteor reached 5.7 knots (11.2 km/h) at 139 rpm with the safety valve set at 60 psi, and engine power was recorded as 530 ihp.
On her trials fitted as triple screw, the Meteor reached 5.25 knots (10.3 km/h) at 139 rpm. Engine power was recorded as 498 ihp. The two wing screws on this trial were 6 ft (1.8 m) diameter, 7 in 6 in (2.29 m) pitch.
Aetna (ii) had two-cylinder 27 in (0.6858 m) diameter 30 in (0.762 m) stroke horizontal single expansion engines of 200 nhp. Her boilers were salvaged from Aetna (i).
Building programme
| Ship | (a) Hull builder (b) Main machinery manufacturers |
Ordered | Laid Down | Launched | Completed | Initial cost | Total Initial Cost |
||
|---|---|---|---|---|---|---|---|---|---|
| Hull | Machinery | to complete for sea |
|||||||
| Aetna class | |||||||||
| Aetna (i) | (a) J Scott Russell, Millwall (b) J Scott Russell |
4 Oct 1854 | 9 Oct 1854 | 3 May 1855 | Never | Never delivered, caught fire during construction | |||
| Meteor | (a) CJ Mare & Co, Limehouse (b) Maudslay, Sons & Field |
4 Oct 1854 | 9 Oct 1854 | 17 Apr 1855 | 4 Jul 1855 | £43,799 | £10,123 | £7,468 | £61,390 |
| Thunder | (a) CJ Mare & Co, Limehouse (b) Miller, Ravenshill & Co |
4 Oct 1854 | 9 Oct 1854 | 17 Apr 1855 | 21 Jul 1855 | £43,784 | £10,343 | £8,210 | £62,337 |
| Broad beam Aetna class | |||||||||
| Glatton | (a) R & H Green, Limehouse (no 314) (b) Miller, Ravenshill & Co |
4 Oct 1854 | 9 Oct 1854 | 18 Apr 1855 | 3 Aug 1855 | £43,479 | £11,244 | £5,858 | £60,581 |
| Trusty | (a) R & H Green, Limehouse (no 315) (b) Miller, Ravenshill & Co |
4 Oct 1854 | 9 Oct 1854 | 3 May 1855 | 13 Jun 1855 | £43,491 | £10,446 | £10,004 | £63,941 |
| Lengthened Aetna class | |||||||||
| Aetna (ii) | (a) Chatham Dockyard (b) Maudslay, Sons & Field |
16 Nov 1855 | 25 Nov 1855 | 5 Apr 1856 | 1866 Harbour service |
£38,357 | £11,000 | £495 | £49,852 |
| Source: Lyon & Winfield, pages 240-2 | |||||||||
Note that whilst Admiralty records for Meteor, Thunder, Glatton and Trusty state that both the Mare and the Green yards were at Limehouse, other vessels built by Mare and by Green were built at Blackwall. It is possible that there is an error in the records, and they were really built at Blackwall.
Fates
- Aetna (i) was to have been launched on 5 May 1855, but caught fire on the building slip, and launched herself two days early. her remains were broken up on the river-bank.
- Meteor was ready in 1855 but reached the Black Sea too late for action. She was laid up in theatre for the winter, and in the Spring, when peace was signed, returned home for the great review of April 1856. The Meteor was used in experimental firing trials in October 1858. She was broken up in 1861.
- Thunder took part in the great review in April 1856 after the end of the Crimean War. She was broken up at Chatham in June 1874.
- Glatton was ready in 1855 but reached the Black Sea too late for action. She was laid up in theatre for the winter, and in the Spring, when peace was signed, returned home for the great review of April 1856. She was broken up in 1864.
- Trusty took part in the great review in April 1856 after the end of the Crimean War. She was used in trials of the new Armstrong 40-pdr BL in January 1859 and the 100-pdr BL in September 1859; contrary to expectations, hits on her armour from the 40-pdr and 100-pdr had no serious effect. She was used in trials with a prototype Coles turret in 1861, and broken up by Castle at Charlton in 1864.
- Aetna (ii) was too late for the Crimean War, and was fitted for harbour service in 1866. She burnt out at Sheerness in 1873 and was broken up in 1874.