Iron ships

[MikeyB]

Was the Ericsson monitor design generally considered superior in all aspects to the ironclad ships Grant and Foote were using in the Fort Henry and Donelson campagign? Or were they generally competitive? When the Union continued to outfit her fleet, which design did they use?

In addition to the iron innovation, was the Monitor also notable for being the first major warship with a 360 turret? Or did this already exist?

Best,
Mike

 

[redbob]

I believe that the City Class Gunboats on the Western waters served the Union's cause much better than the Monitors would have if they had been used there. The Monitors were susceptible to plunging fire which was often a hallmark of ship vs. shore combat on the Western waters and due to their turret design, the Monitors were pretty much limited to a flat trajectory fire which would have limited their usefulness against elevated targets. The City Class boats were also designed to be simple, tough and easily raised and repaired when sunk which can't be said for the much more complicated Monitor Class ships. While the original Monitor had the revolving turret, it couldn't fire directly ahead due to the pilothouse being located forward. This was taken care of in later models by having it on top of the turret which then gave the guns a 360 degree field of fire.

 

[Mark F. Jenkins]

redbob's got it right-- different requirements for different missions. On the rivers, where you were fighting land targets, you needed a high rate of fire vs. big guns-- whereas for combat against other ships, rate of fire was less of a consideration if you had the armor to take a few punches while setting up for a small number of knockout blows. The monitors proved nearly always unequal to the task of land bombardment.

 

[Jimklag]

@redbob is dead right. The riverboats did the job for which they were designed better than a "Monitor" would have.

 

[MikeyB]

Is it just dumb luck that the Monitor design was better suited to taking on the Virginia than its western counterpart? Or did the Navy specifically contract out different designs, knowing what was said above that river and ship-to-ship operations would require different ships?

Does this mean if a Western ironclad steamed to meet Virginia instead of the Monitor, it would have gotten blown out of the water?

 

[rebelatsea]

None of the monitors were capable of 360 degree fire. The funnel and blower uptake grills prevented it. Firing the big MLs over the vents would have had dire consequences below due to blast effects. The western river monitors could take on a CSN ironclad and did at Mobile bay, but the city class and the big conversions would have had a hard time of it not being armoured against heavy MLR or SB shot.

 

[Mark F. Jenkins]

Does this mean if a Western ironclad steamed to meet Virginia instead of the Monitor, it would have gotten blown out of the water?

Absolutely. Even in the match between the weaker Arkansas * and the Carondelet, the Pook Turtle fared quite badly. The Virginia would have had the gunboat way outclassed in firepower and protection.

With one important caveat: the Virginia could never have made it to the mouth of the Mississippi, let alone ascended it very far. She drew at least 21 feet of water.** The Pook Turtles drew less than a third that much. The amount of water available to float the boat factors heavily into how much weight you're going to try to stack on top of it.

_______
* Weaker than the Virginia, I mean.
** The Merrimack's erstwhile sister ship, the Colorado, never did make it into the lower Mississippi despite energetic efforts by Farragut's fleet.

 

[Mark F. Jenkins]

Is it just dumb luck that the Monitor design was better suited to taking on the Virginia than its western counterpart?

Not at all. First, the Monitor was intended to fight against such a target (another ship); and second, the Union was already aware of the intentions to convert the Virginia when the Ironclad Board convened. While it would be far overstating the case to say that the Monitor was specially designed to beat the Virginia (Ericsson's basic design predating the event by years), the threat of the Virginia was certainly a conscious factor in the Board's deliberations and selections.

Now... A number of people, Ericsson among them, had some misperceptions about how effective the monitors would be against coastal land targets. These ought to have been discarded very quickly after the experience at Drewry's Bluff, but the lessons were not learned, and had to be learned again (and again) at Charleston.

ETA: To cite a very noteworthy contrast, that once again provided lessons that were not adequately learned, when the Montauk went up against Fort McAllister in early 1863, she did virtually no damage to the fort (at least no damage that couldn't be rapidly repaired), and showed herself vulnerable to damage in several noteworthy ways (most significantly, she had to be immediately beached when she struck a mine). But when the very same ship ascended the same river to attack another vessel, she was completely successful at it.

As far as the Pook Turtles were concerned, they had some weaknesses that became apparent in use, but the important fact was that they were intentionally designed for the mission they were to be used for, were decently successful at it, and (most importantly) were rapidly made available and ready when they needed to be. (A "Pook Turtle Mk II" would likely have taken some of the weaknesses into account, but things didn't go that way...)

 

[Carronade]

We might also keep in mind that Virginia was about eight times the displacement of the City class - roughly 4000 tons vs. 500 - so it's not surprising that she would be superior in a head-to-head confrontation.

 

[Carronade]

Another thought, the Union casemate ironclads were mostly built or acquired early in the war. After the monitor concept was proven, most new orders were of that type, including ships built on the rivers. These included the Milwaukee class with two turrets, indicating appreciation of the need for a good rate of fire.

 

[Mark F. Jenkins]

While I hesitate to criticize the Eads river monitors... the Osage/Neosho and Milwaukees are among my favorites... they really weren't what the Union needed at the time they appeared. The big Confederate river forts were gone. The "tinclads" were the name of the game by that point-- lots of presence, widespread, fast reaction to trouble spots. (The thing that really would have made the "tinclads" even more effective was some sort of rapid-fire small-caliber weapon like a Gatling; and maybe if the war went on longer, that might have been tried...)

 

[MikeyB]

Not at all. First, the Monitor was intended to fight against such a target (another ship); and second, the Union was already aware of the intentions to convert the Virginia when the Ironclad Board convened. While it would be far overstating the case to say that the Monitor was specially designed to beat the Virginia (Ericsson's basic design predating the event by years), the threat of the Virginia was certainly a conscious factor in the Board's deliberations and selections.

Now... A number of people, Ericsson among them, had some misperceptions about how effective the monitors would be against coastal land targets. These ought to have been discarded very quickly after the experience at Drewry's Bluff, but the lessons were not learned, and had to be learned again (and again) at Charleston.

ETA: To cite a very noteworthy contrast, that once again provided lessons that were not adequately learned, when the Montauk went up against Fort McAllister in early 1863, she did virtually no damage to the fort (at least no damage that couldn't be rapidly repaired), and showed herself vulnerable to damage in several noteworthy ways (most significantly, she had to be immediately beached when she struck a mine). But when the very same ship ascended the same river to attack another vessel, she was completely successful at it.

As far as the Pook Turtles were concerned, they had some weaknesses that became apparent in use, but the important fact was that they were intentionally designed for the mission they were to be used for, were decently successful at it, and (most importantly) were rapidly made available and ready when they needed to be. (A "Pook Turtle Mk II" would likely have taken some of the weaknesses into account, but things didn't go that way...)

Why was the Union navy so ineffectual against large Forts? Was it because these installations were mostly earthen and artillery isn't effective against earthworks? Were ships unable to carry big enough cannon?

 

[Mark F. Jenkins]

Monitors weren't effective against large forts. The Union Navy got rather good at taking down forts, overall. (The winning combination was cooperation with a land force, lots of guns, and moving past the fort to enfilade it or otherwise envelop it.) (Combined arms win.)

Ships versus forts requires some strategy. The principal facts about a fort in this respect is that it's unsinkable and immobile. The ships must use mobility to their advantage, because in a stationary slugging match they are likely to lose.

Masonry (brick) forts were generally more vulnerable than earthworks (Fort Sumter being an exception, but it was in the center of a bunch of other forts, all more or less mutually supporting). Earthwork forts are relatively cheap/quick to build and repair-- the most the ships could generally do is silence them (drive the gun crews from their guns), which is great if you have something else to throw at the target, such as a landing force... not all that great if you're simply silencing the fort repeatedly.

(In this connection, it's worth referring to one of the officers with a lot of experience in this business, David Dixon Porter, who noted that Vicksburg could be passed repeatedly, but merely passing it would not cause it to fall... as he said, ships cannot crawl up bluffs, and it was that part that needed to be taken by the Army.)