Naval guns and gunnery

Naval guns came into general use in the West in the 14th century. They replaced the tactics or ramming or boarding, and became the main naval weapon when it was realized they could sink an enemy ship some yards away, regardless of the wind. From 1500 to 1941 all the major fleets were built around platforms that could shoot bigger and more accurate guns. The aircraft carrier proved itself at the Battle of Pearl Harbor in 1941, ending the era. Naval guns are now used primarily in defense against small boat or missile attacks.

First guns: 15th century

The first guns were simple tubes built up from long bars of iron held together with iron bands. These guns were breechloaders with a separate gunpowder chamber, or servidor, which was wedged into the breech after the stone or iron cannon ball, had been inserted. Muzzle-loading cast-bronze guns came into use soon after the wrought-iron breechloaders. When the Turks besieged Constantinople in 1453, they cast, on the field of battle, bronze guns that weighed 19 tons and hurled 600-pound (270-kg) granite stones. Cast-iron guns came into being soon after cast-bronze guns. Despite distinct advantages of cast iron, problems of controlling the quality of iron retarded its acceptance, and for centuries both heavy cast-iron and ligher cast-bronze guns were used.

The galley used by the English in 1347 against the French at Calais had two guns fixed in the bow of the vessel so as to fire ahead. Two centuries later, cast-iron, cast-bronze, and banded wrought-iron guns were all used aboard ship, as is evidenced by the salvage of the Mary Rose the flagship of English King Henry VIII (sunk in 1545 and salvaged in 1836) which contained guns of all three types. Arrows and stones, used in early guns, gave way to cast-iron balls.

The earliest gunpowder was a finely ground mixture of charcoal, saltpeter, and sulfur. This mixture, known as "serpentine powder," tended to absorb moisture, to separate into its components while being transported; it did not burn if packed too tightly into a gun. By the 15th century gunners used corned powder which was pressed into pellets and screened to a uniform size.

Gun mounts were improved over time. In early galleys, a light gun was placed in a wooden holder and tied to the deck. A heavy post at the breech prevented recoil. Bigger guns would break loose so ropes were used to permit the holder to slide back. Eventually four small wooden wheels were attached to the holder, making a carriage. To check the recoil, a heavy rope or "breeching" was run from the breech of the gun to the side of the ship.

As guns were added to ships, the architecture of the ships was modified radically. Small oar-driven galleys gave way to larger ships powered by sails. In the Mediterranean, the galleass, which used both oars and sails, came into widespread use. Its guns were arranged at intervals along the sides and over the rowers' heads. In the North Atlantic, the galleys were abandoned in favor of small sailing vessels which gradually gave way to larger ships, such as the half-moon shaped galleons. The sailing ship had the advantage that the guns did not interfere with rowers. Large sailing vessels were built with sides curving inward ("tumbled home") above the waterline, thereby strengthening the ship and making it a more steady gun platform, while offering a sloping target to enemy shells.

The gunport was invented by Descharges of Brest, in 1501. Gunports made it possible to post guns on different decks along the sides of the vessel and marked an important step toward the development of the broadside ship. One of the earliest of large armed ships, the new Swedish Makalos, destroyed by the Danes in 1564, carried 178 guns, including 67 cannons and smaller weapons which were mounted on swivels. The Spanish Philip which engaged the English in 1591 carried three tiers of guns on each side with eleven pieces to the tier. This ship also had eight guns forward and several astern. The heaviest gun then in use in the English Navy was the culverin weighing 4,500 pounds (2,000 kg) and firing a 17-pound (8-kg) ball with an extreme range of 2,500 yards. Next in size was the demicannon weighing 4,000 pounds (1,800 kg), which fired a 30-pound (14-kg) ball to 1,700 yards; smaller guns included the cannon-petroe or periers, sakers, minions, and falconets. The effective ranges of these guns were only a small fraction of the extreme ranges because the shells wobbled in flight, losing velocity and accuracy.

Technique for using guns in battle was described as follows in a Spanish lecture of about 1530: Bow guns or broadside guns on the side from which boarding was planned were fired only when the ships were relatively close to each other, the lower guns firing at the waterline and the upper guns and smaller cannon at the sides, sails, masts, and men on the poop deck. The crossbowmen and harquebusiers did not fire until the enemy was very close or in the act of boarding.

The decisive role of the new guns was shown in a sea fight off Preveza, Greece, in 1538 and was confirmed in the victory of the Christians over the Turks in the Battle of Lepanto in 1571. At Lepanto, heavy guns mounted on the galleasses, broke up the charges of Turkish vessels. Small arms such as harquebues, were probably more important than bows and other hand weapons in close-range fighting. In 1588, the English repelled the Spanish Armada in part by using their guns from long range, which prevented the Spanish from closing for hand-to-hand fighting. Thus, in the 16th century, the gun proved to be an important and sometimes decisive factor in naval warfare. This was formally recognized in 1618 when the English Commission on Naval Reform reported that sea fights were "chiefly performed by the great artillery breaking down masts, yards, tearing, raking, and bilging the ships. ..."

Ships of the line

Mounting 60 to 80 heavy guns the battleships of the era, called "ships of the line" had to grow bigger. Smaller and more flexible were the frigates. Both were redesigned to maximize firepower. The "Royal Sovereign", launched in 1637, was probably the first three-decked English warship and she proved extremely serviceable. Her builder, Phineas Pett, described her armament in his journal:

Her lower tyre [tier] hath thirty ports which are to be furnished with demicannon and whole cannon ... ; her middle tyre hath also thirty ports for demiculverin and whole culverin; her third tyre hath twentie six ports for other ordnance; her forecastle hath twelve ports, and her half deck hath fourteen ports; she hath thirteen or fourteene ports more within board for murdering pieces, besides a great many loope-holes out of the cabins for musket shot. Shee carrieth moreover, ten pieces of chase ordnance in her right forward, and ten right aff [aft], according to lande service in the front and reare.

A British history of naval architecture published in 1851 shows drawings of this vessel superimposed on drawings of a ship of the mid-19th century; aside from its greater beam, the 19th-century vessel was amazingly similar to the 17th-century Royal Sovereign. It was the archetype of naval vessels for the next two centuries and marked the rise of the full-fledged broadside ship.

The first of 12 Spanish three-deck ships-of-the-line was the Real Felipe (1732-50), which displaced 1,965 tons, carried a crew of 1,250, and mounted 114 guns. Its most significant action occurred with the French against the English in the Battle of Toulon in February 1744.

After victory in the Seven Years War (1756-63), Britain allowed its great fleet to literally rot--66 ships sank because of rotting wood. Reform came during the War for American Independence, and in the critical year 1781 the French, Spanish and Dutch allies had about 168 major warships of 60 or more guns, versus 114 for the British (and none for the United States). The French defeated the British off Yorktown in 1781, fiorcing the surrender of the main British army in America. Finally in 1782 the British recovered and sank the French fleet at the Battle of the Saints in the West Indies to regain control of the seas.

A "ship of the line" was a main battleship, built from 2,000 oak trees and carrying 74 or so guns, each effective out to 300 yards. Battles had to be fought close in, with marines essential as sharpshooters and boarding parties.

The texhniques of gunnery remained surprisingly static before the 1870s. The ship of the line, or broadside ship, with heavy guns mounted on the lower deck just above the waterline and with lighter guns on higher decks, remained the dominant factor in naval warfare despite many small improvements.

Frigates

The frigate was the most glamorous ship in the British navy during the era of Napoleonic seapower. Frigates made up a quarter of the 412-ship royal fleet in wartime, and were kept in active service during peacetime. The frigate had between 32 and 44 guns and a crew of 217 to 297 men. While not as big as the ship of the line, it could outrun anything with more firepower and catch commercial ships, sloops, and corvettes. It could handle a variety of tasks, including raiding coastlines, running down opposing ships, and scouting.

Frigates were used for reconnaissance, convoys and raids. Sloops were even smaller and cheaper; their 20 guns were enough to overpower any merchant ship, or control rivers and bays. In the American revolution John Barry, a 30-year-old Philadelphian and senior captain of the almost-landlocked American navy in 1778 Barry commanded the "Raleigh", a 700-ton frigate with 36 guns and 235 crewmen. In late September 1778, the "Raleigh" engaged the "Unicorn", a 22-gun ship, and the Experiment, a 50-gun ship-of-the-line. Barry lost the "Raleigh" and 135 men were captured, but he disabled the "Unicorn" and escaped with 86 men.

On 23 September, 1779, a Franco-American squadron under John Paul Jones was off Flamborough Head, England, looking for British merchant ships to capture, when the British frigates "Countess of Scarborough" and "Serapis" bore down on it. The American frigate, "Bonhomme Richard" engaged the "Serapis". In a particularly bloody, destructive fight, the English captain called out to inquire if the "Bonhomme Richard" had struck her colors. Jones cried out, "I have not yet begun to fight!" Upon raking the "Serapis", the crew of the "Bonhomme Richard" led by Jones boarded the English ship and captured her. Likewise, the French frigate Pallas captured her prize the Countess of Scarborough. The action stuck out as an embarrassing defeat for the Royal Navy, who suffered the capture of two of her vessels in her own home waters, but goes down in history as the most memorable ship-on-ship gun battle in history.

The era of dominance by frigates ended when "big" frigates like the "USS Constitution" appeared in the waters.

Gunnery science

Gunnery was a mysterious art because every element was variable. Shot was never uniform, because of careless manufacture and rusting in storage. Gunpowder varied even more in terms of strength and burning rate; the bore of the guns varied in size; even the mathematical laws governing the trajectory projectiles through the air varied among mathematicians. A British scientist, Benjamin Robins (1707–1751), in the 1740s, put forward basic theories and supporting experimental data which put ballistics into the framework of Newtonian mechanics and formed the basis of the science of ballistics. For example, by applying Newton's second law to velocity measurements at varying ranges, Robins measured the air-resistance that slowed balls in flight. Robins proposed that the bore of the cannon be enlarged, that they be equipped with snug-fitting balls, and that they be fired with decreased charges of powder. This, he argued would increase destructive power, since the larger ball with a relatively low velocity would do more damage than would a smaller one. He further urged that careful attention be given to designing new guns to eliminate unnecessary weight.

In A Proposal for Increasing the Strength of the British Navy (1747) Robins proposed a new naval gun design based on his models, and in 1779, the carronade was invented to incorporate Robins' ideas. These short-barreled, light-weight, large-bore guns used a small powder charge and the same projectile as did the long guns. As Continental scientists like Leonhard Euler developed Robins' ideas, Navies across Europe hurried to adopt Robins' proposals. The British put carronades on existing ships and armed many of the smaller warships, such as frigates, sloops, and brigs, entirely with carronades. Similar guns were put into service by the Dutch, French, Spanish, and American navies. The carronade's short range eventually led to loss of interest in it as a naval weapon. In two actions during the War of 1812, this shortcoming was an important factor in determining the victor. In the Battle of Lake Erie, American forces fought with long guns from beyond the range of British ships, and the English commodore reported, "We remained in this mortifying situation five hours, having only six guns in all the squadron that would reach the enemy, not a carronade being fired." In another action, the British ships Phoebe and Cherub, armed with long guns, captured the American frigate Essex, which was equipped almost entirely with carronades. Despite its shortcomings, the carronade demonstrated the importance of quick-firing weapons and the need to use projectiles which fitted snugly into the bore of the gun.

Fire ships and mortars=

Naval gunnery focused on the broadside ship and the long guns that served as decisive elements in combat. For other naval purposes, however, other gunnery devices were used. The "fire ship" which was loosed into enemy ship concentrations was a weapon of antiquity. With the development of gunpowder, powder ships were used in preference to fire ships. For example, in a 1693 attack on the French port of Saint-Malo, the British Commodore Benbow loaded a galliot with 100 barrels of powder and 340 chests containing cannon balls, iron chains, large pieces of metal, and other destructive missiles. This ship was cast adrift and grounded on a rock in the harbor where it exploded, blowing down part of the town wall and severely damaging the houses.

In addition to powder boats, bomb ketches were used for attacking facilities ashore. These were equipped with mortars, cannon with a large bore and a short barrel which threw their projectiles at a high angle and were particularly well suited for attacking targets protected by heavy walls. The French in the siege of Algiers in 1681 used seven bomb ketches, or galliotes-à-bombes, each mounting two mortars, some of which were 14-inch caliber and threw 140-pound projectiles. These projectiles were perforated or laced envelopes containing conbustibles and were ignited by the explosion of the propellant charge.

Explosive shells

Hollow shells filled with gunpowder proved more effective than fire. The powder was exploded by means of a slow match (burning fuse). Bomb ketches came to be widely used for bombarding seaports and shore fortifications. Explosive shells and incendiary carcasses were also fired from long guns ashore. However, the risk of fire or premature explosion was so serious that there were only isolated examples of firing explosive shells from long guns afloat. In 1788, for example, the Russian government fitted a flotilla of long boats with brass ordnance and attacked a Turkish squadron at the mouth of the Liman River on the Sea of Azov and, through the use of explosive shells, gained a complete victory. Throughout the period of the French Revolution, the French experimented with explosive and incendiary projectiles, but experienced many disasters to their own ships as a result.

Explosive shells became popular thanks to a French artillery officer, Henri Joseph Paixhans, who in the 1820s proposed a new system of ship armament based on their use. Paixhans showed how the new steam-powered ship could become a warship. He argued that all guns aboard a ship be of the same bore--and that explosive shells be used, thereby simplifying their use and augmenting their destructiveness. In experiments strikingly similar to work performed a decade earlier in the United States by Robert Stevens, Paixhans demonstrated that explosive shells could destroy wooden ships, and he proposed to protect the ships by encasing their sides with iron plates; this led to the development of armored naval vessels. Although Paixhans' system was not adopted in its entirety, the French in 1829 standardized on a single caliber (a 30-pounder) which was made in different weights for use on the various decks and classes of ships. Some eight years later, the French adopted a Paixhans-design shell gun, but of much larger bore than the 30-pounder. The British reacted almost immediately to this second decision and in 1839 adopted six patterns of 32-pound long guns, associating with them a few eight-inch shell guns. Other countries quickly added the Paixhans guns to their naval ordnance, and the correspondence of the United States Navy Department for the 1840s contains many references to ships furnished with Paixhans' guns.

In 1837, Captain T. F. Simmons of the British Royal Artillery proposed a system in many ways the reverse of that advocated by Paixhans. Instead of standardizing on a maximum number of short-range guns, Simmons advocated arming ships of war with a few long guns of maximum caliber and muzzle velocity and using other guns of the same caliber but of lesser weight and range for the upper decks. In short, he argued that instead of crowding as many guns aboard ship as space would permit, the most powerful guns that the ship could safely carry and fire should be used and that their number should be limited by the over-all capacity of the vessel. Although this line of thinking did not immediately predominate in the design of naval vessels, its impact can be seen in the design of battleships in the later years of the 19th and on into the 20th century.

Projectiles

The projectiles which were used through the early 19th century varied depending upon the target. Solid cast-iron balls were used in attacking the hulls of other ships. Chain shot, consisting of two shot secured to each other with a length of chain, and bar shot, consisting of two solid hemispheres secured by a bar, were effective at short range against sails and rigging but were very inaccurate in their flight. Canister and grape shot were used against the crews. Canister was a tin cylinder fitting the bore of the gun and packed with musket balls. Grape shot was larger balls held in a cylindrical frame. Both types broke up on leaving the muzzle, with the clustered balls dispersing.

Shrapnel

Grape and canister fell into disuse after a British army officer, Henry Shrapnel, devised a thin-cased shell containing musket balls and a powder bursting charge. A burning fuse ignited the powder while the shell was in flight and liberated showers of small missiles. Hot shot also came into use against wooden hulls. It was fired with just sufficient velocity to splinter the wooden sides and render them favorable for burning when ignited by the heat of the ball. Experiments were also conducted with shells filled with molten iron or with phosphorus dissolved in carbon disulphide, which would ignite spontaneously on exposure to the atmosphere after bursting. These projectiles inevitably fell into disuse with technological advances.

The 19th century gunnery revolution

The 19th century saw striking advances in technology. The steam engine was adopted for marine propulsion after 1820; ships were built of iron after 1850; armored naval vessels came into being; and guns increased in size and power. These developments occurred almost simultaneously and affected each other. Steam was not only used to power the ship but also provided for mechanical handling of the guns, which freed them from limitations in size that had been imposed when only manpower was available. The use of iron as a structural material permitted larger ships than had been possible with wood, and larger guns could consequently be carried. The same metallurgical advances upon which iron hulls and armor plate were based permitted the design of stronger guns. The development of armored ships demanded comparable development in the power of naval guns. As the armor grew thicker and stronger the guns had to be more powerful, and the entire ship much larger and more stable.

Many steps were involved in this process and basic advances were sometimes abandoned because they were beyond the technology of the day. For example, the first naval vessel to be fitted with screw propellers, the U.S. Navy's "Princeton", was also fitted with two 12-inch, wrought-iron guns. These guns proved to be beyond the metallurgy of the period and during a public demonstration in 1844 one of them burst, killing five people including high officials. In 1854 a British engineer, William Armstrong, perfected techniques for making guns of wrought iron. Almost simultaneously, Alfred Krupp of Germany began making guns from cast steel ingots. Their fabrication techniques made possible the high-power guns which came to characterize naval ordnance. Krupp and Armstrong each designed breech-loading mechanisms and fitted their guns with both rifled and smooth-bore barrels. Considerable development was necessary before the breechloaders achieved definite superiority over muzzle-loaders. The greater range, velocity, and accuracy which were the advantages of rifled guns were offset by the higher stresses imposed on the barrel and by other design problems. Rifled small arms had been in use for hundreds of years, but their advantages of greater accuracy and longer effective range were largely offset by the disadvantage of slow rate of fire until elongated bullets permitting rapid loading were developed in the mid-19th century by the French. To provide strength to withstand the increased working pressure of large rifled guns, the French in 1859 adopted a system of reinforcing with hoops of puddled steel. Other European nations followed suit.

During the American Civil War, Lt. John M. Brooke of the Confederate Navy fabricated rifled cast-iron guns hooped with wrought-iron rings. The greater portion of American effort, however, went into improving cast-iron smooth-bore guns. John A. Dahlgren of the U.S. Navy followed ideas first suggested by Benjamin Robins nearly a century earlier and, building on the work of Paixhans and others on proportioning guns, greatly improved the shape of long guns. He determined the exact amount of strain and its location within the gun and attempted to proportion the parts of the gun with reference to this strain. He thereby completely abandoned both the ornamentation and the traditional shape for heavy guns. T. J. Rodman of the U.S. Army devised a system of casting guns hollow and cooling the inner surfaces while the metal hardened. This redistributed the strain within the gun and overcame the elastic peculiarities of cast iron, making it possible to cast guns with a bore of up to twenty inches and a gross weight of nearly 60 tons, but with a life comparable to that of smaller guns. The same technique, however, increased the life of smaller guns by a factor of ten to twenty times.

Turrets

The old wooden naval gun carriages mounted on wheels and using a heavy rope breeching to absorb recoil were replaced by iron carriages fitted on an inclined slide. Various devices, such as the friction of interlaced iron plates, were used for absorbing recoil. The gun carriages were fitted with wheels running on concentric tracks, thereby simplifying the training of the guns. The pivot gun, achieving its best development during the War of 1812, offered a 70 degree arc of fire but still required the ship to be turned for fore and aft targets.

American John Ericsson and Royal Navy Captain Cowper Phipps Coles developed the first practical revolving turrets. Ericsson's 1854 design was used on the "Monitor" (1862) and the coastal ships of that type during the Civil War. Coles designed a turret for a raft in 1855 and took out a patent for an improved design in 1859. A Danish warship built in Britain in 1863 had two revolving turrets based on Coles's design. The Royal Navy began using turreted guns in 1864. Seagoing Royal Navy turret ships of the 1860s had masts and rigging, a protective forecastle, and a poop, which limited the arc of fire to 120 to 132 degrees. The weight of the hull armor, turrets, and masts made these ships dangerously top heavy. The steam-powered Devastation, built in 1873, was the first ocean-going turreted warship and the first modern battleship. The Coles turret system became the standard until the 1890's. Steam powered turntables, however, offered far from perfect control of the turning motion, and in the mid-1870s, William Armstrong perfected the application of hydraulic power to gun turrets. As developed by the Armstrong Company of Great Britain and applied in the "Dreadnought" (1875), hydraulic power was applied to all the principal operations of working the gun, such as checking the recoil and moving the gun in or out along the slides and ramming home the powder and charge. Thus, the basic problems of designing carriages for heavy naval guns were solved. The U.S. Navy adopted electric drives, which were eventually superseded by variable-speed gears. Power drives were also utilized on the smaller secondary batteries which served tactically for close-range attacks. The battleship turret, developed in the 1860s, was a mainstay of naval armament from the 1870s until the 1940s.

Naval race

The naval race in technology pitted the Italian "Duilio" and the British "Inflexible", both completed in 1876. The Italians first planned to use four 35-ton guns on the "Duilio", but in response to the manufacturer's offer to make guns of much greater weight and power determined to adopt 60-ton guns. The British, who had planned to install 60-ton guns on the "Inflexible", then decided to mount 16.5-inch guns weighing 80 tons. The Italians in turn adopted 17.7-inch guns weighing 100 tons for the "Duilio". This competition indicated that the striving for superiority in individual ships was one of the guiding principles of naval construction.

The increase in size of guns was in part caused by an increase in the length of the barrel. Longer barrels gave the projectiles a greater velocity, but posed other problems. As gun barrels became longer, muzzle loading became impossible; the British adopted breech-loading guns in 1880 as other European navies had done earlier.

Innovations in powder

To obtain maximum effectiveness from the longer barrel, the burning rate of the gunpowder needed to be closely controlled. Much experimentation was performed on the effect of size and shape of powder particles on rate of burning, and larger grains were provided for larger guns. Changes in composition were also experimented with, and in the 1880s brown powder made from under-burnt charcoal was adopted as one means of decreasing the burning rate. A serious drawback of these gunpowders was that only about half of the mixture was converted into gas, the remainder becoming a dense smoke. The French in 1886 adopted smokeless powder made of nitrocellulose (gun-cotton). Four years later, the Royal Navy began using smokeless powder made from a nitroglycerine base. Both these compounds liberated four to five times as much energy as did the black powder used earlier. In addition, these chemically homogeneous powders could be formed readily into grains so shaped as to control the rate of burning. This gave a uniform pressure, permitting a higher projectile velocity without straining the gun. Black powder continued in use as an igniter for the propellant charge, particularly in the larger guns. With later developments, propellants consisting of either nitrocellulose or nitroglycerine were described as "single-base" powder; others containing both were described as "double-base"; and a third category containing nitrocellulose, nitroglycerine, and other chemicals was called "triple-base" or "multiple-base." At the close of the 19th century, the U.S. Navy followed the lead of the French and adopted a nitrocellulose powder as a propellant charge.

20th century

Armor was the central issue by the late 1880s. If any one factor can be isolated as stimulating developments of the later years of the 19th century--improved materials (wrought-iron and then steel), increases in size, improvements in projectiles, mechanization, and improved powder--it was the necessity of penetrating armor, which was also rapidly developed and which gave ships an ever higher degree of protection. Much of the improvement to guns appears to have been accomplished without much attention to the fact that the ranges of guns were also being greatly increased. The emphasis upon short range might best be illustrated by recalling that, between the Civil War of 1861-65 and the Spanish-American War of 1898, ramming was looked on as a naval tactic of an importance comparable to that of gunnery.

Fire control

The necessity of fighting at maximum range, which was gradually recognized, called for a high degree of accuracy so that shells could be placed on a target many miles distant. In 1892, a U.S. naval officer, Bradley A. Fiske, invented the telescopic sight, with which guns could be aimed more accurately, particularly at long range. About 1906, the introduction of periscopic gun sights greatly improved positions for gun pointers and trainers. Still later, range finders provided an accurate means of measuring the distance to a target. Exploitation of the capabilities thus given to naval guns is attributed largely to Percy Scott of the British Navy and William S. Sims of the U.S. Navy. These men championed the importance of accurate long-range shooting and devised training techniques whereby the potential which had been given to naval guns could be achieved.

Before the outbreak of World War I, the British and Germans introduced the "director" system of fire. Guns were placed in parallel alignment and by means of electrical control were aimed and fired in salvos from an elevated position. Optical range finders and electrical instruments to aid in fire control were mounted in these elevated positions. Under this system, not only was the fire of all guns controlled from a single elevated point, but the shot fell together in a small pattern which could be "spotted" on the target. This led to a great extension of range and made it possible to fire in heavy weather which obscured the vision of the gun crews. The elevation that could be given to guns on British ships was increased from 13½° in 1909 to 40° in 1917. After the end of the war the U.S. Navy achieved further refinements in fire control, such as having each ship fire shells with a distinctive color in bursting so that the shots of each could be distinguished. Techniques were also developed for spotting by use of cruisers or aircraft, and night firing was perfected through the use of star shells which burst over the enemy. Through such techniques the effective range of the modern 16-inch (41-cm) naval rifle came to be approximately 20 miles (32 km).

The vulnerability of large but weakly protected battle cruisers at the Battle of Jutland (1916) left battle cruisers with an uncertain role in the postwar fleets. The Washington Treaty (1922) designated battle cruisers as capital ships because they were armed with guns over 203 mm. The treaty designated heavy cruisers as those with guns over 155 mm, and light cruisers as those with guns under 155 mm. The signatory navies of the U.S., Britain, Japan, France, and Italy at first concentrated on heavy cruisers and later on light cruisers. Spain also built two heavy and six light cruisers. Just before 1939 new types appeared, such as antiaircraft cruisers, submarine cruisers, and new battle cruisers; the U.S. built the world's last battle cruiser in 1944.

World War I

The encounter of great battleship fleets was the centerpiece of all war planning from 1900 to 1945, following the strategic ideas of American Alfred Thayer Mahan. Yet it happened only once, and that was short and inconclusive. At the Battle of Jutland (May 31-June 1, 1916), the British battle cruiser squadron, consisting of six battle cruisers and four battleships, by chance encountered a scouting squadron of five German battle cruisers. They engaged each other in a running battle. Unknown to each side, each squadron was closely followed by their main battle fleet, and soon the entire main fleets of both sides were in view. The British fleet was stronger and the Germans decided to retreat instead of fight; they narrowly escaped. Although the German forces were outnumbered and their guns were of shorter range than those of the British, they still managed to inflict more damage on the British than they suffered in return. The military importance of the engagement was not great. The British lost three battle cruisers, three armored cruisers, and eight destroyers, while the Germans lost one battleship, one battle cruiser, four light cruisers, and five destroyers. The Germans claimed a victory, pointing out the greater losses of the British fleet. The British battle cruisers blew up when hit by German shells because of their faulty gunnery technique. In an effort to increase the rate of fire, gun crews kept far more than the regulation charges inside their turrets, and also kept loaded not only the primary ammunition supply system, but also the auxiliary hoists and waiting positions. Thus, many charges were exposed to flash when the turret was struck by a German shell, resulting in an explosion sufficient to sink the ship.

The tactical objectives of gunnery policy were accurate deliberate fire at long ranges in good visibility, and effective rapid fire at short ranges in the event of poor visibility. By 1914, the British Admiralty developed a secret technical-tactical system that was intended to destroy the German battle fleet within five minutes through rapid independent fire at medium range while at the same time avoiding the threat posed by German torpedoes. The synthesis was never tested in battle, however, for the Germans did not act as the British expected. Moreover, by emphasizing this synthesis, the British failed to acquire adequate gunnery equipment for shooting at long range, creating vulnerabilities when the Grand Fleet encountered the German fleet at the Battle of Jutland in 1916. Brooks (2005) seeks to correct what he sees as the negative prevailing view of the Dryer Table system of gunnery fire control used by British warships at Jutland. He argues that the system worked well in the battle and that it was a superior system to the competing Argo method. Brooks further alleges that the British cruiser losses in the battle were due to tactical errors made by Vice Admiral Sir David Beatty rather than any flaw in the Dryer Table.

Although the British were disappointed with their showing, the German fleet was driven back to its ports and rarely, in the two remaining years of the war, was it able to leave them. The great German fleet was indeed useless in the face of the more powerful Royal Navy. so hundreds of naval guns up to 380mm bore and 47,000 meter range were removed from the ships and sent by railway to deploy on the Western Front.

Further development of powder

In World War II night engagements proved that standard smokeless powder created a flash that temporarily blinded the ships' crews. Various flash suppressors were devised and mixed with the powder, which was formed into grains for small guns and into pellets for the larger guns. The British used a multiple-based powder, Cordite N, which was relatively flash-free, but which the U.S. Navy considered to be brittle, unduly sensitive to shock, and hazardous in hot climates. As a result the U.S. developed other flashless powders and was placing one of them, Albanite, in large scale production at the end of World War II.

Despite the adoption of smokeless powder, black powder still continued in use as a burster charge for projectiles until just before World War I, when more powerful and less sensitive explosives were adopted. In the U.S. Navy, trinitrotoluene (TNT) was adopted for smaller projectiles and Explosive D (ammonium picrate) for the larger ones. These continued in use throughout World War II, although by the end of the war more powerful explosives had come into use, particularly in the smaller antiaircraft projectiles. If the entire spectra of powder uses is considered--torpedoes, mines, aerial bombs, and rockets, as well as large and small projectiles--the trend in explosive development, beginning with the adoption of smokeless powder, was to recognize the special demands of various uses and to formulate specialized compounds tailor-made to particular requirements.

End of the battleships

The Royal Navy sank the Italian fleet in Nov. 1940 at the Battle of Taranto using warplanes from aircraft carriers. The Japanese took note and at the Battle of Pearl Harbor (Dec. 7. 1941), sank nearly the entire American battleship fleet using carrier planes. Immediately the carrier replaced the battleship as the capital ship of seapower. The era of big-gun battles between fleets at 30,000 yards was (almost) over. Heavy guns were useful for shore bombardment, but for combat were replaced by bombs delivered by air, and torpedoes (delivered bvy airplane, submarine, or destroyer) as the chief offensive weapons of naval warfare.

The role of naval gunfire in supporting amphibious operations remains of importance. Beyond the scope of this form of bombardment, seaborne weapons also have a share in the delivery of nuclear ballistic missiles against targets deep in continental landmasses; this mission involves the use of missiles fired underwater from submarines.

Anti-aircraft gunnery

The rapid development of the warplanes after 1914 necessitated a means of defense. Guns of secondary batteries were given sufficient elevation for use in air attacks, and projectiles and fuses for use against aircraft were developed. With the onset of World War II, 20mm Oerlikon (which were too light) and especially 40mm Bofors automatic guns were used in increasing numbers, especially against Japanese Kamikaze planes.

Anti-aircraft gunnery was a tradeoff between 5" guns, with their long range, and 20 and 40 calibre short-range guns with a high rate of fire. The breakthrough came in 1943 with the introduction of the proximity fuze (or "VT fuze") in 5" shells. It had a radio and receiver and when a signal bounced back, it was within range of the target, and exploded. The effect was to make the target 50 times bigger and thus much easier to hit. The fuzes played a decisive role in defeating the Japanese Kamikaze attacks of 1944-45. The British had invented the device but lacked the massive industrial capacity needed to produce it in quantity, so shared the blueprints with the U.S. Navy. The basic components are a vacuum tube (six inches long and three inches in diameter) a battery, and a radio transmitter and receiver, all of which have to be rugged enough to withstand 20,000 Gs when shot out of a gun at high velocity. After the shell is fired and begins rotating, a chemical reaction produces an electrical charge which in turn arms the shell and sends out a radio impulse. The return signal, reflected from the target, detonates the shell prior to impact and produces the devastating effects.

To the 21st century

Since the end of World War II, the emphasis within antiaircraft defense batteries has shifted from these weapons to 3- to 5-inch (8-13-cm) guns fitted for automatic loading and aiming. The rate of fire of these guns has been greatly increased over that of earlier guns of similar sizes.

Missiles

After 1960 another revolution was initiated--that of the guided missile. The influence of the guided missile on warfare has been comparable in effect to the introduction of the gun in the 14th century, steam and mechanization in the 19th century, or the aircraft in the 20th century. Early missiles were launched from shore bases or from aircraft, and with the exception of the German V-2 rocket, were essentially unmanned aircraft; however, the overall capability of missiles has been greatly extended in the postwar years.

Missiles are classified by their launching vehicle and target as air-to-air, air-to-surface, surface-to-surface, underwater-to-surface, or surface-to-air. This classification clearly indicates their relationship to other naval weapons: the air-to-air missile is replacing the gun in naval aircraft; the air-to-surface missile, the aerial bomb; the surface-to-surface and underwater-to-surface missiles the long-range heavy gun; and the surface-to-air missile is replacing the antiaircraft battery. Many U.S. cruisers, destroyers, and aircraft carriers are fitted with surface-to-air missiles. Other naval powers also have guided-missile ships in operation. Most guided-missile ships are still equipped with guns, although the trend is toward increasing the number of missile batteries and decreasing the number of guns.

Aegis system

The threat of enemy missile attacks required a radical rethinking of command and control operations. Traditional reaction time, firepower and operational availability in all environments no longer matched the threat. In the 1960s the U.S. Navy developed an Advanced Surface Missile System (ASMS), renamed AEGIS in 1969.

AEGIS is designed as a complete system, integrating state-of-the-art radar and missile systems. The missile launching system, the computer programs, the radar and the displays are fully integrated to work together. This makes the AEGIS system the first fully integrated combat system built to defend against advanced air, surface and subsurface threats. The AEGIS combat system is highly integrated and capable of simultaneous warfare on several fronts -- air, surface, subsurface and strike. Anti-air warfare elements include the radar system AN/SPY-1B/D, command and decision system and weapons control system.

See also

• Explosives
• Gunpowder