Talk:Passaic-class monitor

WikiProject Military history/Assessment/Tag & Assess 2008
Article reassessed and graded as start class. --dashiellx (talk) 17:34, 17 June 2008 (UTC)

Applique armour rings
" Later improvements included... rings fitted around the turret and pilot houses to prevent their pivoting machinery from being jammed by shot."

This is poorly phrased and may be as a result of persistent confusion over the nature of knocked-out turrets on Passaic-class ships in the Battle of Charleston. There was never any indication that machinery damage resulted in such a manner that it could be prevented by the application of armour rings around the bases of the turrets or pilot houses. Any derangement of machinery would be the result of solid bows against the turret jarring the machinery inside through shock; extra armour at the base would have no influence on this phenomenon one way or the other - shock of impact is still shock of impact.

As Reed and Eads both made clear in their criticism of the Ericsson-type monitors, the matter was with the base ring upon which the turrets sat, coupled with the softness of the iron produced in the early 1860s. Any solid impact against the turret sides was liable, as Reed explains, to create deformation and spreading downwards of the iron plate. This would then create a point of impingement upon the turret's bearing ring such as to create an insurmountable degree of friction, requiring such force from the turning machinery of the turret as to gouge the brass ring if rotation were to be achieved. The friction was, of course, far too great for the machinery to overcome, resulting in jams from solid blows to the base of the turret side.

(Eads cautioned against the use of deck-mounted bearing rings as seen on Ericsson's ships on the basis that any twisting of the hull - associated with normal sea service - would warp the plane of the bearing ring and similarly create a point of friction which the drivetrain could not overcome - Reed discusses this.)

The actual reason for the applique armour rings on the outside of the turret base of Passaic-class monitors (as well as pilot houses) was to absorb the deformation resulting from such shots and to confine the spreading to an area which was both outboard of the ring and clear of the deck itself, thus preventing any impingement upon the bearing plane or resultant jamming. 2A00:23C7:3119:AD01:6CB5:2010:4049:EE92 (talk) 12:00, 8 December 2022 (UTC)