Casco class monitor
Encyclopedia
The Casco-class monitor was a unique class of light draft
monitor
built on behalf of the United States Navy
for the Mississippi
theatre during the American Civil War
. The largest and most ambitious ironclad program of the war, the project was dogged by delays caused by bureaucratic meddling. Twenty ships of the class were eventually built at great expense, but proved so unseaworthy when trialed that they were quickly sidelined, causing a public scandal.
monitor CSS Virginia
from breaking the Union
blockade at Hampton Roads
in spring 1862, the navy became enthused with the monitor concept (at the expense of the larger broadside ironclad type), and ordered a number of new classes of monitor, one of which was the Casco class. The Casco was a unique "light draft" class designed specifically for operating in the shallow bays, rivers, and inlets of the Confederacy.
The specifications for the Casco class originally called for a vessel with a light draft
, not exceeding six feet, and a low freeboard
to present the smallest possible target to Confederate guns. For the design of the new class, the Navy turned once again to John Ericsson
, designer of the USS Monitor.
Ericsson came up with a design for a 225 feet (68.6 m)-long vessel with a single revolving turret containing two 11 inches (279.4 mm) guns, an armored upper deck, and twin screw propellers giving a top speed of around eight knots. Around the hull of the vessel, a large wooden "raft" was to be constructed, which would help increase buoyancy. Ericsson kept the design deliberately simple in keeping with the inexperience of the private shipyards which would be called upon to build them. He anticipated that each ship would take no more than forty days to complete.
Alban C. Stimers
, to whom was entrusted the power of setting general plans and ship specifications. Stimers, an ambitious man, was keen to take credit for the design of the new monitors and frequently visited Ericsson's bureau to make changes to the specifications.
The greatest single alteration to the design however, came not directly from Stimers but from Admiral Joseph Smith, chief of the Bureau of Yards and Docks
in Washington, D.C.
, who suggested that the oval hull of the ship be surrounded by large iron tanks which could be pumped full of water in order to lower the ship's freeboard still further when in combat to present an even smaller target, or drained for normal travel. Stimers liked the idea and ordered the changes, but when Ericsson saw the new plans he resigned from the project. The new plans greatly added to the design's complexity, requiring sophisticated pumping mechanisms, while the added weight would also reduce speed and buoyancy.
in Chester, Pennsylvania
, Wilcox & Whitney at Camden, Harlan & Hollingsworth in Wilmington, Delaware
and Merrick & Sons of Philadelphia (the latter of whom subcontracted much of the work to William Cramp & Sons). A number of smaller firms were also contracted. The cost was estimated at $395,000 per ship, or approximately $8 million in total. Some shipyards, such as Cramp, were forced to substantially upgrade their ironworking facilities for the production of the new vessels.
By the end of 1863, frequent design changes were causing growing problems for the contractors. Stimers and his team of thirty draftsmen at the monitor office continued to submit changes even as the vessels were in the process of production, leading to long delays. One yard in Boston received a total of 83 drawings and 120 letters of explanation from Stimers, and the specification manual for the ships grew to 92 pages of small print. The final design called for a total of thirteen auxiliary engines and pumps per ship, fancy brasswork in place of cast iron, and a complex system of pipes for draining and filling the water tanks. The added weight to a ship designed with only a 15 inches (381 mm) freeboard at the outset raised questions about the ships' eventual seaworthiness.
By this stage, the twenty vessels, in various stages of completion, had cost half a million dollars apiece. Amid public scandal, the Navy set up an inquiry. Stimers was found responsible and removed from his post, and the Navy appointed experienced administrators in his place. The vessels were redesigned and refitted in order to improve buoyancy, but few of them saw active service before the end of the war and those that did were decommissioned and laid up within months, while the majority were never commissioned at all. Within a few years, all the ships of the Casco class had been retired and scrapped or otherwise disposed of.
Draft (hull)
The draft of a ship's hull is the vertical distance between the waterline and the bottom of the hull , with the thickness of the hull included; in the case of not being included the draft outline would be obtained...
monitor
Monitor (warship)
A monitor was a class of relatively small warship which was neither fast nor strongly armoured but carried disproportionately large guns. They were used by some navies from the 1860s until the end of World War II, and saw their final use by the United States Navy during the Vietnam War.The monitors...
built on behalf of the United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
for the Mississippi
Mississippi River
The Mississippi River is the largest river system in North America. Flowing entirely in the United States, this river rises in western Minnesota and meanders slowly southwards for to the Mississippi River Delta at the Gulf of Mexico. With its many tributaries, the Mississippi's watershed drains...
theatre during the American Civil War
American Civil War
The American Civil War was a civil war fought in the United States of America. In response to the election of Abraham Lincoln as President of the United States, 11 southern slave states declared their secession from the United States and formed the Confederate States of America ; the other 25...
. The largest and most ambitious ironclad program of the war, the project was dogged by delays caused by bureaucratic meddling. Twenty ships of the class were eventually built at great expense, but proved so unseaworthy when trialed that they were quickly sidelined, causing a public scandal.
History
After the success of the US Navy's first monitor, the , in preventing the ConfederateConfederate States of America
The Confederate States of America was a government set up from 1861 to 1865 by 11 Southern slave states of the United States of America that had declared their secession from the U.S...
monitor CSS Virginia
CSS Virginia
CSS Virginia was the first steam-powered ironclad warship of the Confederate States Navy, built during the first year of the American Civil War; she was constructed as a casemate ironclad using the raised and cut down original lower hull and steam engines of the scuttled . Virginia was one of the...
from breaking the Union
Union (American Civil War)
During the American Civil War, the Union was a name used to refer to the federal government of the United States, which was supported by the twenty free states and five border slave states. It was opposed by 11 southern slave states that had declared a secession to join together to form the...
blockade at Hampton Roads
Hampton Roads
Hampton Roads is the name for both a body of water and the Norfolk–Virginia Beach metropolitan area which surrounds it in southeastern Virginia, United States...
in spring 1862, the navy became enthused with the monitor concept (at the expense of the larger broadside ironclad type), and ordered a number of new classes of monitor, one of which was the Casco class. The Casco was a unique "light draft" class designed specifically for operating in the shallow bays, rivers, and inlets of the Confederacy.
The specifications for the Casco class originally called for a vessel with a light draft
Draft (hull)
The draft of a ship's hull is the vertical distance between the waterline and the bottom of the hull , with the thickness of the hull included; in the case of not being included the draft outline would be obtained...
, not exceeding six feet, and a low freeboard
Freeboard (nautical)
In sailing and boating, freeboardmeans the distance from the waterline to the upper deck level, measured at the lowest point of sheer where water can enter the boat or ship...
to present the smallest possible target to Confederate guns. For the design of the new class, the Navy turned once again to John Ericsson
John Ericsson
John Ericsson was a Swedish-American inventor and mechanical engineer, as was his brother Nils Ericson. He was born at Långbanshyttan in Värmland, Sweden, but primarily came to be active in England and the United States...
, designer of the USS Monitor.
The monitor office
At around the same time however, the Navy created a new "monitor office" to centralize oversight of the new monitor program. The new office, located across the hall from Ericsson's design bureau, was nominally headed by Rear Admiral Francis H. Gregory, but was effectively run by Chief EngineerChief Engineer
In marine transportation, the chief engineer is a licensed mariner in charge of the engineering department on a merchant vessel. "Chief engineer" is the official title of someone qualified to oversee the entire engine department; the qualification is colloquially called a "chief's...
Alban C. Stimers
Alban C. Stimers
Alban Crocker Stimers was a Chief Engineer with the United States Navy. He assisted with the design of the Navy's first ironclad, the , and later with the design of the Passaic-class monitors...
, to whom was entrusted the power of setting general plans and ship specifications. Stimers, an ambitious man, was keen to take credit for the design of the new monitors and frequently visited Ericsson's bureau to make changes to the specifications.
The greatest single alteration to the design however, came not directly from Stimers but from Admiral Joseph Smith, chief of the Bureau of Yards and Docks
Bureau of Yards and Docks
The Bureau of Yards and Docks was the branch of the United States Navy responsible from 1842 to 1966 for building and maintaining navy yards, drydocks, and other facilities relating to ship construction, maintenance, and repair....
in Washington, D.C.
Washington, D.C.
Washington, D.C., formally the District of Columbia and commonly referred to as Washington, "the District", or simply D.C., is the capital of the United States. On July 16, 1790, the United States Congress approved the creation of a permanent national capital as permitted by the U.S. Constitution....
, who suggested that the oval hull of the ship be surrounded by large iron tanks which could be pumped full of water in order to lower the ship's freeboard still further when in combat to present an even smaller target, or drained for normal travel. Stimers liked the idea and ordered the changes, but when Ericsson saw the new plans he resigned from the project. The new plans greatly added to the design's complexity, requiring sophisticated pumping mechanisms, while the added weight would also reduce speed and buoyancy.
More design changes
In February 1863 the monitor office offered contracts for twenty of the new Casco-class monitors, in spite of the fact that the original architect, Ericsson, had not approved the new design. Winning bidders included prominent firms like Reaney, Son & ArchboldReaney, Son & Archbold
Reaney, Son & Archbold was a short-lived 19th-century American iron shipbuilding company located on the Delaware River at Chester, Pennsylvania...
in Chester, Pennsylvania
Chester, Pennsylvania
Chester is a city in Delaware County, Pennsylvania, United States, with a population of 33,972 at the 2010 census. Chester is situated on the Delaware River, between the cities of Philadelphia and Wilmington, Delaware.- History :...
, Wilcox & Whitney at Camden, Harlan & Hollingsworth in Wilmington, Delaware
Wilmington, Delaware
Wilmington is the largest city in the state of Delaware, United States, and is located at the confluence of the Christina River and Brandywine Creek, near where the Christina flows into the Delaware River. It is the county seat of New Castle County and one of the major cities in the Delaware Valley...
and Merrick & Sons of Philadelphia (the latter of whom subcontracted much of the work to William Cramp & Sons). A number of smaller firms were also contracted. The cost was estimated at $395,000 per ship, or approximately $8 million in total. Some shipyards, such as Cramp, were forced to substantially upgrade their ironworking facilities for the production of the new vessels.
By the end of 1863, frequent design changes were causing growing problems for the contractors. Stimers and his team of thirty draftsmen at the monitor office continued to submit changes even as the vessels were in the process of production, leading to long delays. One yard in Boston received a total of 83 drawings and 120 letters of explanation from Stimers, and the specification manual for the ships grew to 92 pages of small print. The final design called for a total of thirteen auxiliary engines and pumps per ship, fancy brasswork in place of cast iron, and a complex system of pipes for draining and filling the water tanks. The added weight to a ship designed with only a 15 inches (381 mm) freeboard at the outset raised questions about the ships' eventual seaworthiness.
Scandal and inquiry
By spring of 1864, the first of the Casco class vessels, the , was ready for her initial trial. Putting to sea, waves washed across the deck, while the stern remained totally submerged by three or four inches (10 cm). A second trial, of the , confirmed the disaster, with waves washing over the deck and the ship only able to make a speed of 3½ knots as opposed to the original specification of eight. Moreover, the trials were conducted "light", without the normal operational loads of coal, ammunition and stores. The ships were unseaworthy and virtually useless.By this stage, the twenty vessels, in various stages of completion, had cost half a million dollars apiece. Amid public scandal, the Navy set up an inquiry. Stimers was found responsible and removed from his post, and the Navy appointed experienced administrators in his place. The vessels were redesigned and refitted in order to improve buoyancy, but few of them saw active service before the end of the war and those that did were decommissioned and laid up within months, while the majority were never commissioned at all. Within a few years, all the ships of the Casco class had been retired and scrapped or otherwise disposed of.