Philadelphia+Naval+Shipyard+Ironclad+Conversion

The Philadelphia Naval Shipyard has the distinction of being America’s first Navy Yard, as its establishment was originally to serve as a ship building facility that would give birth to both the U.S. Navy and Marine Corps. Through two centuries of service, the Yard would serve as a national institution that would be at the center of numerous significant changes that influenced the course of American history. The correlation between the demands made upon the Navy Yard with its eventual development and expansion, reflect how strategic naval planning gauged production aims by integrating technological innovation and relevant process improvements. Through its long history, the Philadelphia Navy Yard has served as a hub of technological implementation that successfully incorporated Naval research into efficient ship manufacturing. The Philadelphia Navy Yard has a legacy of remaining flexible to meet the needs required by national policy, varying from golden ages of production in the Ironclad and World War II eras to virtually ceasing production in its final twenty years.

media type="custom" key="5644387" media type="custom" key="5643781"Reasons for Growth of the Philadelphia Naval Shipyard

Credited as the father of the modern concept of sea power, Captain Alfred Thayer Mahan once said that, “The highest function of a Navy Yard is to maintain the fleet in efficiency in war…and no utility in peace will compensate for the want of this in war.” The original Philadelphia Navy Yard of 1801 suffered major limitations as a base that would maintain a fleet for naval operations, as it was situated 100 miles from the Atlantic Ocean. Philadelphia was chosen as the location for the Yard after it was decided that the trade-off of placing the Yard in a less strategic location far outweighed the interruption of commerce in the ports of New York and Boston. In the early nineteenth century, Philadelphia and the surrounding Delaware River communities emerged as the premiere region for design and development of wooden sailing ships and later iron steam power warships. The Yard became a center for the implementation of technological and organizational change in navel shipbuilding, beginning with the application of screw propeller technology to steam powered warship engines.

The outbreak of The Civil War in 1861 forced Americans to reconsider the potential functions of The Philadelphia Naval Shipyard. As the confederacy claimedall of the country's southern naval yards, The Philadelphia Shipyard was relied upon to continue the Union’s naval war efforts. The Yard built, converted and outfitted over 100 ships during the Civil War. The Yard’s ability to perform under the stresses of wartime initiated the need for structural growth. In 1876, the Yard relocated to League Island. Philadelphia provided an influx of engineers, constructors and architects whose contributions helped to circumvent natural obstacles that had previously posed as barriers to structural expansion. From the onset, League Island was constructed as a fully functional industrial ship manufacturing and repair facility. The construction of two dock yards, a supporting railroad network and proximity to sources of steel/coal provided infrastructure to support the large and demanding work projects of League Island. This allowed for the construction of new machine shops and forges that would be required for mass scale production while balancing the growth of residents, businesses and industries in the greater Philadelphia area. League Island was used as a test site for progressive, civic-oriented improvements. Examples of these include new sewer and freshwater pumping systems as well as electric lighting and elevators. Philadelphia and the surrounding areas benefited greatly from the testing and progressive thinking taking place at League Island.

Technological innovations into the twentieth century produced new naval weapons which required the discretion and skilled expertise of Philadelphia’s labor force (welders, etc.). After nearly twenty years characterized by a bottleneck in government funding, the lack of global stability caused by World War I demanded investment for the expansion of the American Naval Fleet. The assortment of sensitive military targets vulnerable to sabotage called for anti-submarine patrol and escort vessels. The expansion of the workforce to meet these newly imposed demands swelled shipyard employment from 2,500 workers in 1916 to roughly 12,000 in 1919. Encouragement from the government to organize security and preparation measures led to the construction of steam generating plants, barracks, steel sheds, and storehouses to accommodate for the growing size of the base. Notably, at this time, League Island carried one of the Navy’s largest cranes, weighing in at over 350 tons and providing a huge mechanical advantage.

Leading up to World War II, the Great Depression caused the Yard, once again, to lose government funding. By 1940, the severity of the war’s progression mandated that the government mobilize a new generation of naval weaponry, producing a “Second Renaissance” for the Yard. To answer unparalleled production requests, the Yard would employ a labor force that swelled to 47,000 strong. Remarkably, changes made in senior management personnel and improvisation to combat resource shortages led to a reduction in project delays. Logistical and operational adjustments would grow the Philadelphia Shipyard into the world’s largest naval installation, credited with launching about fifty new warships while converting or overhauling 1,218 other vessels. Following the Philadelphia Shipyard’s success in World War II, the growing military-enterprise complex that was exacerbated by the Cold War, marked the beginning of the end for the base.

Although minor ship-building efforts continued through the 1950’s-‘60’s, an increasing trend of the government was the practice of soliciting private contractors for the research, development, and manufacturing of naval vessels. The last ship constructed at the Philadelphia Shipyard was in 1970, as the Cold War caused another shift in the role of the base. As in the case of other countless public shipyards, the Philadelphia Naval Shipyard was assigned repair and overhaul work. Areas of specialized expertise included fossil-fueled surface combatants, high-pressure steam turbine engines, electronics, and combat systems installation. Upgrading out-dated vessels, the Yard would continue to dredge along with its multi-million dollar upkeep costs, eventually resulting in the decision to shut the base down permanently.

media type="custom" key="5643813"Construction and Production at the Naval Shipyard

The Philadelphia Naval Shipyard did a few things differently during the construction of its ironclad ships. There was doubt surrounding the ability of iron manufacturers to produce iron plates large enough for the shipbuilding. Pennsylvania, however, was able to produce enough of these steel plates to fortify every vessel in the Navy. The shipyard constructed the ironclad ships by creating an iron casing for the wooden ship that was fixed together without the use of bolts, rivets or crevices on the exterior of the ships surface.

Due to Philadelphia’s proximity to Pittsburgh and its steel industry, the Philadelphia Naval Shipyard was a logical location for the construction and repair of vessels. The Philadelphia Naval Shipyard was dedicated purely to the building and reaping of vessels during the time of ironclad conversion. From the shipyard, a great number of vessels were produced, many of which were “the pride of the nation.” A few examples are the U.S.S. Pennsylvania, U.S.S. North Carolina and U.S.S. New Ironsides.

During the war with Spain in 1873, twelve ironclad monitors were transferred to the Philadelphia Naval Shipyard and thirteen vessels were rebuilt in the next three years. The League Island location, for the next decade, became neglected more and more with many of the dikes and buildings becoming dilapidated. In spite of this, the funding for the construction of 78 new ships between 1881 and 1891 revitalized the Naval Shipyard. During this time, the newest technology in shipbuilding was applied to the newly commissioned ships. These technologies included rolled steel plating, steel rifled ordnance, and triple expansion steam engines. Among major ships were the Atlanta, Boston, Chicago, Dolphin, Baltimore, Newark, Philadelphia, Yorktown and dynamite cruiser Vesuvius. A full history of construction, from 1815 to 1970, can be seen in the appendix.

media type="custom" key="5643797"The Technologies of Nineteenth Century Warships

Before analyzing the technologies that made the ironclad ship the most superior naval technology of its time, the ships that preceded it must be analyzed. The best naval warship before the ironclad was the ship-of-the-line. This was a wooden vessel that, until the 1820’s, used wind and sails as its means of propulsion. This was the most common warship design for decades before the ironclad. Ships-of-the-line were built for the purpose of fighting in what is known as a battle-of the-line. These battles were fought by opposing fleets of ships that would line up next to each other so that each fleet’s ship’s broadsides were facing the enemy. With each ship’s broadside aimed at the enemy, the ships-of-the-line were able to effectively gun down and fight the enemy fleet. The technologies associated with ships-of-the-line reflect this type of combat. Ships-of-the-line were classified according to how many guns they had, which could range anywhere from seventy-four to one-hundred and thirty-six guns on up to four decks. The primary design was built for either speed and maneuverability or sheer power, which involved the largest number of guns. Ships-of-the-line, depending on the specific design, had several other features designed to maximize its effectiveness in a battle-of-the-line. This included a thick hull that could be as large as twenty-four inches or more, and a tapered deck design, where the size of the deck decreased from the bottom to the top. This design made the ship very stable and generally difficult to sink. Ships-of-the-line were generally not sunk in battle, but disabled by destruction of its mast and then boarded and taken by the enemy.

Ironclad ships used an entirely different method of fighting and design from ships-of-the-line. The ironclad was defined by three major technologies, armor, propulsion and firepower. All three were completely different from a ship-of-the-line and other wooden ships of the day, such as frigates, and rewrote the rules of naval warfare until the Dreadnaught era. The very first experiments with ironclad ships showed that the hulls were generally impervious to standard cannon fire. Armor of more than two inches was generally effective enough to defend a ship. This was difficult to do with iron technologies of the time, so ironclads typically had multiple layers or plate iron protecting them. As armor technology improved, shipbuilders discovered a design that plated the ship with armor at an angle. When the hull was hit by a projectile that was traveling parallel to the water line, most of the kinetic energy would be deflected form the ship at an angle, reducing the effectiveness of enemy weapons. Because iron of the time was rather brittle, most ironclad ships were build by plating iron on top of a wooden hull. The wood made the hull more pliable and much more effective in combat. Because the armor of ironclads rendered most gunfire ineffective, many ironclad ships were built with powerful rams to pierce enemy ships' hulls in order to sink them.

Because the standard cannon of the day was ineffective against an ironclad ship, the armaments of an ironclad ship did not focus on a large volume of fire power, like the multi-deck ship-of-the-line, but instead, just a few very large caliber cannons and rifles. Some of these cannons could have a diameters in excess of fifteen inches and fire cannonballs over 400 pounds more than a mile. Because these ships may have only one or two large guns, these guns needed to have a great deal of maneuverability. The armor turret was developed on the ironclad ship, with a box cylindrical design that helped defend it from enemy fire.

The last defining piece of technology for the ironclad ship was its main source of propulsion. The first ironclads were a combination of steam and sail driven. This allowed these ships to be both fast in short runs and be capable of making long overseas voyages since average steam power only allowed ships to carry about 9 days worth of coal. However, as the steam engines effectiveness increased, ironclad ships moved away from being sail-driven and became entirely steam-powered. These engines were connected to the relatively new technology, the screw propeller. The screw was submerged entirely underwater, making it more effective than designs such as paddlewheels. Many early ironclads had mechanisms that allowed the screws to be retracted into the armor of the ship to reduce drag when sailing, but this also proved to be a good technique for protecting the screw during battle.

media type="custom" key="5643799"Conclusion

The Philadelphia Naval Shipyard is an immensely important part of American Naval history. The Yard's long history has changed with the times, from wooden vessels with sails to nuclear powered submarines. The ironclad conversion, however, is one of the most notable technological feats with which the Yard is credited. During this time period, hundreds of ships were constructed or modernized to meet the needs of changing naval warfare. Iron workers, coal miners, welders, engineers, construction workers, and military personnel were all a part of the enormous task of keeping America's naval technology current and cutting edge. Early forms of iron vessels still relied on wooden frames due to the brittle nature of steel, but in time, warships became entirely metal. This alone completely changed the face of naval conflict. No longer were traditional weapons effective against modern vessels. Moreover, the implementation of other technologies never before seen, like the screw propeller and steam powered ships, are historically rooted in the Philadelphia Shipyard. The Yard continued to play its role, modernizing and constructing new vessels, through the twentieth century, two World Wars and the Cold War, but eventually closed due to increasing utilization of private contractors for technological advancement.

media type="custom" key="5643803"References

media type="custom" key="5643997"Appendix
 * 1) Dorwart, Jeffery M., and Jean K. Wolf. The Philadelphia Navy Yard. Philadelphia: Univ. of Penn., 2001. Print.
 * 2) Hess, Ron, Jefferson P. Marquis, John F. Schank, and Malcolm MacKinnon. The Closing and Reuse of the Philadelphia Naval Shipyard. Arlington: RAND's National Defense Research Institute, 2001. Print.
 * 3) Jenkins, Mark F. "Ironclad Technology." Ironclads and Blockade Runners of the American Civil War. 1998. Web. 11 Mar. 2010. .
 * 4) "Ship of the Line." Tall Ships. Web. 11 Mar. 2010. .
 * 5) <span style="font-family: Arial,Helvetica,sans-serif; font-size: 12px; line-height: normal;">Smith, Merritt R. Military Enterprise and Technological Change: Perspectives on the American Experience. Cambridge: MIT, 1985. Print.