The ''Passaic''-class
ironclad
An ironclad is a steam engine, steam-propelled warship protected by Wrought iron, iron or steel iron armor, armor plates, constructed from 1859 to the early 1890s. The ironclad was developed as a result of the vulnerability of wooden warships ...
monitors
Monitor or monitor may refer to:
Places
* Monitor, Alberta
* Monitor, Indiana, town in the United States
* Monitor, Kentucky
* Monitor, Oregon, unincorporated community in the United States
* Monitor, Washington
* Monitor, Logan County, West Vir ...
of the
U.S. Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage of ...
saw service in the
U.S. Civil War
The American Civil War (April 12, 1861 – May 26, 1865; also known by other names) was a civil war in the United States. It was fought between the Union ("the North") and the Confederacy ("the South"), the latter formed by states t ...
and the
Spanish–American War
, partof = the Philippine Revolution, the decolonization of the Americas, and the Cuban War of Independence
, image = Collage infobox for Spanish-American War.jpg
, image_size = 300px
, caption = (clock ...
. The class was an improved version of equipped with a 15-inch
Dahlgren gun
Dahlgren guns were muzzle-loading naval artillery designed by Rear Admiral John A. Dahlgren USN (November 13, 1809 – July 12, 1870), mostly used in the period of the American Civil War. Dahlgren's design philosophy evolved from an accidental ...
in place of one of the 11-inch guns.
Design
Naval architect and engineer
John Ericsson
John Ericsson (born Johan Ericsson; July 31, 1803 – March 8, 1889) was a Swedish-American inventor. He was active in England and the United States.
Ericsson collaborated on the design of the railroad steam locomotive ''Novelty'', which com ...
designed the ''Passaic''-class warships, drawing upon lessons learned from the first , which he also designed. The ''Passaic'' monitors were larger than the original ''Monitor'' and had their pilothouses atop the turret, rather than near the bow. This allowed a wider field of view and easier communications between captain, pilot and crew. The shape of the hull was an improvement; a fuller and rounder lower hull, far more boat-like than that of the ''Monitor'', and with a less pronounced overhang. The ''Passaic'' class featured an funnel and improved ventilation. In combination, the significant hydrodynamic refinements and improved draught to the boilers resulted in a one-knot speed increase over the prototype monitor, despite the ''Passaic'' having a lower
specific power
Power-to-weight ratio (PWR, also called specific power, or power-to-mass ratio) is a calculation commonly applied to engines and mobile power sources to enable the comparison of one unit or design to another. Power-to-weight ratio is a measuremen ...
than ''Monitor'' (''Passaic'' being almost 400 tons heavier and yet with the same 320ihp-rated machinery).
Having observed the new 15-inch
Rodman cannon
Drawing comparing Model 1844 8-inch columbiad and Model 1861 10-inch "Rodman" columbiad. The powder chamber on the older columbiad is highlighted by the red box.
The Rodman gun is any of a series of American Civil War–era columbiads designed by ...
in fortifications and disappointed with the performance of the 11-inch Dahlgren versus ,
Assistant Secretary of the Navy
Assistant Secretary of the Navy (ASN) is the title given to certain civilian senior officials in the United States Department of the Navy.
From 1861 to 1954, the Assistant Secretary of the Navy was the second-highest civilian office in the Depar ...
Gustavus Fox
Gustavus Vasa Fox (June 13, 1821 – October 29, 1883) was an officer of the United States Navy, who served during the Mexican–American War, and as Assistant Secretary of the Navy during the Civil War.
Life and career
Fox was born at Saugus, Ma ...
required the new monitors to be equipped with at least one gun of 15-inch caliber, resulting in rush production of a new 15-inch Dahlgren. The turret was in diameter inside with the gun mounted flush because the muzzle diameter was too large for the turret opening. The large volume of propellant gases released inside the turret required the addition of a "smoke box" at the muzzle in the interior of the turret.
[Olmstead, ''The Big Guns'', p. 94] As a result, the 15 in gunners could not see their targets and had to aim with the or guns. ''Lehigh'' had her 11-inch smoothbore replaced with an 8-inch
Parrott rifle
The Parrott rifle was a type of muzzle-loading rifled artillery weapon used extensively in the American Civil War.
Parrott rifle
The gun was invented by Captain Robert Parker Parrott, a West Point graduate. He was an American soldier and invent ...
. ''Passaic'' also had this modification by July 1863, and, eventually, all surviving members of this class had an additional 15-inch smoothbore added.
Later improvements included an additional 50 tons of deck plating over the magazines and machinery spaces as well as rings fitted around the turret and pilot houses to prevent their pivoting machinery from being jammed by shot.
Ships in class
Warships of ''Passaic'' class included:
*
''Passaic''
*
''Montauk''
*
''Nahant''
*
''Patapsco''
*
''Weehawken''
*
''Sangamon''
*
''Catskill''
*
''Nantucket''
*
''Lehigh''
*
''Camanche''
The first ship of the class was named for the city of
Passaic, New Jersey
Passaic ( or ) is a city in Passaic County, in the U.S. state of New Jersey. As of the 2020 U.S. census, the city had a total population of 70,537, ranking as the 16th largest municipality in New Jersey and an increase of 656 from the 69,78 ...
.
See also
* , an
Imperial Russian Navy
The Imperial Russian Navy () operated as the navy of the Russian Tsardom and later the Russian Empire from 1696 to 1917. Formally established in 1696, it lasted until dissolved in the wake of the February Revolution of 1917. It developed from a ...
monitor type built to the plans of the American ''Passaic'' class.
Notes
References
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{{Union ironclads
Monitor classes