Iron and coal: first modern warships
The ironclad Numancia
Evolution of the ship of the line
Genesis of the armored warship
The Crimean War of 1853-1856 defined the essential elements of the subsequent generation of warships: steam propulsion, armored protection and
explosive ammunition. To begin, we have to differentiate between armored construction and iron construction. The French floating batteries - and
later the British copycats - were of wooden construction, covered with iron plates. The experiments carried out by the British demonstrated that the iron of
that time was too inconsistent to ensure its resistance against shellfire. Consequently, the HMS Birkenhead, first frigate of iron construction, was
remodeled as a troop transport. Her shipwreck in the vicinity of the South African coastline in 1852 could not be attributed to her iron construction,
but to the large openings practiced in the bulwarks during a remodelation which eventually resulted fatal for the ship.
Albeit the British Admiralty forbid iron construction for a while, armored protection was still valued. It was known that two French ironclad
gunboats had endured a total of 135 impacts, virtually without casualties, during the Battle of Kinburn in 1855. However, no decisive step was took to
embrace a construction system which would have rendered obsolete the largest part of the Royal Navy, and this order of things would have continued
like this if it were not for the French naval builder Dupuy de Lome. His triumph of 1858, represented by his ironclad Gloire, first oceanic vessel
of this type, was a challenge for his rivals.
The Gloire was a ship of wooden construction, of the two-deck type but reduced to a single deck, protected by iron plates of four inches in thickness
placed externally along the waterline. She introduced a new profile, very low for a capital ship, because the heavy armor could not be applied to the
hull of a ship of multiple decks. Her machinery was powerful enough to exceed 13 knots and initially it inspired enough confidence for discarding a rigging,
but later three masts were added. In those years of inefficient and voracious machines, the British warships retained their riggings for many years
to ensure the required operational range. Meanwhile, the French saw in the Gloire, which was armed with thirty-six 68-pound muzzle-loading rifled cannons,
the immediate response to the unarmored ship of the line of wooden construction, and promptly they ordered more units.
The ironclad HMS Warrior
However, before the Gloire sailed, the British presented their own challenge, the project for the HMS Warrior. Launched in the last days of 1860, she
demonstrated that the prejudice against iron construction had been overcome. Her iron structure had enough solidity for supporting the protection and
the subdivision to a degree which was impossible for the French wooden ship. But unlike in the Gloire, only the central battery was protected, including
transversal bulwarks which completed an armored box or citadel. Both ends lacked any protection on a length of about 24 meters
and this was compensated with a heavy subdivision. A critical defect of the HMS Warrior was that the lack of protection compromised the steering devices.
In this regard the British ironclad was inferior to the French counterparts, which enjoyed integral protection on a rather shorter hull.
Unlike the French counterparts, the British ironclad was built in a style closer to which had been seen during the last centuries of the age of sail.
Instead of a rect prow fitted with a ram, the hull featured a clipper bow spruced up by a figurehead and a modest ornamentation. The ample galleries
astern, fitted with a total of seventeen windows and some other modest ornamentation, represented the luxury typical of the classic ship of the line,
a luxury which in 1860 had its years numbered (the French ironclads had been deprived of stern galleries from the very beginning). The length of the
hull reached 115.82 meters, with a beam of 17.8 meters and a draught of 8.2 meters. The HMS Warrior was more slender than the French ironclads and
resulted faster as well.
Note: the hull of the HMS Warrior was built in the Blackwall Shipyards of Thames Ironworks, the same place in which the famous
"Blackwall frigates" had been built since 1837, and perhaps the only British shipyard in that time in which an iron hull could be built.
The iron armor had a thickness of 114 millimeters in both the sides and the bulwarks and was backed up by 460 millimeters of teak wood in the sides. It
encompassed thirteen portholes on each side, granting protection to the twenty-six 68-pound muzzle-loading smoothbore cannons which formed the main
armament, complemented by ten 110-pound breech-loading rifled cannons and another four 40-pound pieces of similar characteristics. The armor, extending
4.9 meters above the waterline and 1.8 meters below it, was riveted to the iron hull through the teak, which had the purpose of absorbing the shock waves
caused by impacting projectiles to prevent the breaking of the rivets. Each armor plate was 4.57 x 0.91 meters in size and weighed four tonnes. The displacement
of the HMS Warrior reached 9284 tonnes and the countless rivets contributed not little to this.
The propulsion plant comprised a horizontal two-cylinder reciprocating steam engine which could develop 5772 indicated horse power thanks to the steam
generated by ten rectangular boilers with four furnaces each. A horizontal engine had the advantage of a lower profile which increased stability while
decreasing the chances of being hit by a projectile. The two pistons drove a single 30-meter 50-tonne shaft through huge cranks, having each piston a stroke of about 60
centimeters. The cylinders had to be huge because the boilers delivered steam at low pressure; the steam engines of that time were very inefficient.
In fact, the engine worked at a maximum of 56 revolutions per minute, but since the moving parts were uncovered this speed was maddening and dangerous enough.
The bronze propeller had two blades, seven meters in diameter and a weight of about 25 tonnes. This element could be detached from its shaft and hoisted
to the deck to reduce the hydrodynamical drag when navigating exclusively by sail. For this onerous operation were required about 600 men (almost
the whole complement of 705 crewmen). At a maximum rate of revolutions the propeller allowed a maximum speed of 14.3 knots and with the help of the sails
the HMS Warrior was able to reach the incredible speed of 17.5 knots. But the steam engine was not used often and this justified the task of dismantling
The ship carried 850 tonnes of coal which granted an operational range of 2100 nautical miles at 11 knots. The limited coal capacity meant that the steam
engine was reserved as a tactical advantage in combat rather than used for regular navigation. Hence the HMS Warrior usually navigated exclusively by sail,
and in these conditions the two funnels could be retracted so they did not mean a hindrance for maneuvers. Sailing allowed a top speed of 13 knots, really
good for a ship of her size fitted with a sail area of up to 5100 square meters, which was not greater than that of a first-rate ship of the line from the
Napoleonic Era. But anyway the French ironclads were equipped with much lesser sail plans, which allowed for very reduced speeds. The French Navy had decided
to rely in the steam machinery for regular propulsion and use sails as a complement or for emergency propulsion.
The HMS Warrior as museum ship
When she was launched the 29th December 1860, the HMS Warrior was the most powerful warship on the world. But soon she was rendered obsolete by the fast technical progress. The
change was a consequence of the American Civil War and the Monitor. This primitive overseas creation was soon followed by the HMS Devastation
in 1871, the first battleship fitted with rotatory turrets and deprived of rigging, which left definitely outdated any broadside ironclad. The HMS Warrior
traveled by the last time by her own means the 14th May 1883, reaching Portsmouth, where she remained attached to the most diverse tasks.
In 1902 she was a mothership for torpedo boats and in 1904, remaned as Vernon III, she was attached to the Vernon Torpedo School and docked at Portchester Creek.
In 1923 she was decommissioned but no buyers were found for her. Since her hull was in optimal conditions, in 1929 she was towed to Milford Haven for being used
as a fuel depot ship in Pembroke Dock, remaining in such role until 1976. However from 1967 it was considered the idea of restoring the eminent ship and a
foundation was constituted for such purpose.
In 1979 she was towed to Hartlepool, where it was seen that the task of restoring the hull would be harder than expected. It was uncertain whether the budget
which had been estimated between four and eight millions of sterling pounds would be enough, for to the corresponding cleaning works had to be added large amounts
of deep knowledge, skill and style, something that one century after her construction would not be easy to find. But eventually, after almost 60 years of
ostracism, the 16th June 1987, the waters of Portsmouth welcomed her with honors, and nowadays the HMS Warrior remains there, exhibited afloat and wholly completed,
both externally and internally.
However we cannot say that the restoration is totally accurate, as the ship was originally fitted with wooden masts, not with the steel masts that we can see
nowadays. Also the largest part of the ropes are made of either synthetic or metallic fibers. Another difference from the original ship is the number of yards, for the
restored ship lacks royal sails. It is understandable that for keeping a museum ship economically viable some concessions have to be done regarding the materials
adopted, for wood and natural fibers suffer from a much faster deterioration. For further protection the ropes are painted with tar.
The museum ship has been fitted with good replicas of Armstrong artillery pieces, all of them mounted in sliding carriages. On the upper image we can
see one of the 110-pound breech-loading rifled cannons placed on the weather deck. These pieces, of caliber 178 millimeters, were installed as well
on the ends of the gun deck, outside the citadel. On the lower image we can see one of the 68-pound smoothbore muzzle-loading cannons. These pieces,
of caliber 206 millimeters, were installed inside the citadel. The 68-pound cannon was certainly the most traditional model but also the most reliable one.
Rifled cannons offered better precision but the breech-loading mechanisms of that time were not reliable enough for standard utilization. Because of
this these experimental weapons were placed in unprotected positions. The 68-pound cannon was fitted with rudimentary sights and the elevation of the tube
was regulated by means of simple wedges.
On the space between gun ports there was a dining bench and in this place the crew members slept on hammocks hanging from the beams. The distance between
gun ports was 4.57 meters, by far the greatest of any contemporary warship. This rendered the HMS Warrior as an unusually comfortable warship, but also
as an excessively long one. At the same time, it was a good idea to reduce the size of the gun ports, for obvious reasons of protection. For this to be
possible the gun carriages were fitted with a slide bar running along their center and which pivoted on a pintle in the mouth of the gun ports. This
allowed to keep the muzzle pointing always towards the gun port.
Inside the citadel, the twenty-six 68-pound cannons are displayed with their full rigging and the various ammunitions that they could fire: a solid shot,
a cylindrical case shot, a grape shot filled with fifteen balls, an explosive shell filled with powder, a shrapnel shell filled with 340 pellets and
an incendiary shell to be filled with molten iron. This latter was particularly dangerous to manipulate, specially in wooden ships. The whole gun deck
is enlivened with ammunitions, gunnery tools, buckets and individual weapons (rifles and sabers). In essence, everything is similar than it was in a
classical ship of the line, but the HMS Warrior offered greater comfort and specially greater protection. Also in those years the sailors started to be
equipped with uniforms, more suitable for bad weather conditions.
While advanced in some ways and well known for her great strength and speed, the HMS Warrior was in fact very unresponsive to steering commands. Despite all
the new advances her steering devices were basically like those used during the 18th century: a simple system of ropes and pulleys manually operated via
a number of steering wheels. As a ship increased in size, the solution was simply to increase the number. Whereas large ships of the line had two steering
wheels, the HMS Warrior and other ironclads had four. Still, it was tough to control the ship because her weight and length were already excessive for a purely
manual system. Besides, the steering wheels and binnacles were placed outside the citadel. This was the Achilles heel of the HMS Warrior: in comparison with
French ironclads she had worse maneuverability and higher risk of losing her steering during battle.