A displacement of a max of 10,000 tons, max guns of 16.5 inches, single turret main armament, no more than two guns in that turret, and only four secondary guns between 5.1 to 8.3 inches.
But the loophole is if these ships are under 5,000 tons and guns under 12 inches aren't counted against the tonnage limits for cap ships.
The TL is in my sig, New Balance. And yeah the RN gets to keep those 15 inch monitors as there are a lot more tonnage to play around with. But monitors are brought in because of butterflies ITL where there are more of them and because of the scrapping causes ITL where you can save guns and turrets.
The Howe is most famous for being the only battleship to singlehandedly sink another battleship during World War II.
What was overlooked at the time was that the Giulio Cesare was older, slower, lighter armed and lighter armoured, and
her task force was outnumbered and outgunned almost two to one, and that the convoy the Italians were protecting
made their destinaton more or less unopposed.
But monitors are brought in because of butterflies ITL where there are more of them and because of the scrapping causes ITL where you can save guns and turrets.
A displacement of a max of 10,000 tons, max guns of 16.5 inches, single turret main armament, no more than two guns in that turret, and only four secondary guns between 5.1 to 8.3 inches.
But the loophole is if these ships are under 5,000 tons and guns under 12 inches aren't counted against the tonnage limits for cap ships.
When considering conversion designs for the Tennessee-class armored cruiser, a modification to the existing 10" guns was considered that would have allowed them to be angled upwards to 40(!) degrees.
This would allow the guns to penetrate an OTL treaty cruiser (such as Pensacola) at up to 31,000 yards, compared to the 18,000 yards previously for total penetration.
That's just by modifying the turret mounts alone. The gun would need a new edition, as they were 25 years old by the twenties... This is circa the 1929 War Plans (source: Norman Friedman, U.S. Cruisers: an Illustrated Design History)
I really don't see why its any better than the original 13.5" ships? Why would it be worth the extra cost of scraping and replacing them to get a less powerful ship?
That entiely depends on what you want your ship to do.
Older and larger ships have (a) higher fuel and maintenance costs and (b) larger crew requirements.
They also have (c) a deeper draught.
If you want a coastal bombardment type vessel, then a shallower draught vessel is much better (Gets closer). As for running costs, I can see why a cheaper to run ship is more advantagous (sp) in several cases, even though you have to build it. As another has said the main time and cost of a new warship are the guns and armour. If you can reuse those items off an older ship, you actually have a fairly cheap ship (All things considered) to build. You can also build it quicker as it takes a few years to produce the armour and guns (Usually they are ordered 1 to 2 years before the hull).
The Lord Clive class monitor had 12" guns on 6,150 tons. I don't see why there couldn't be a smaller version using the twin 9.2" turrets from the last Armoured Cruisers or Lord Nelson class Pre-Dreadnoughts. If that puts you over the 5000ton limit you could use one of the single 9.2" mounts from redundant ships.
Didn't several of the WW1 & 2 monitors also recycle the barbettes as well as the turret/guns? If that pattern is followed, there's some sizing issues to deal with on the height/width of the barbette.
Just to point out, I've actually been working on an armored aviation cruiser for the late teens/early 20s that uses an evolved Mk 4 10"/48 gun system. Overall has a 14,306 ton light displacement, and a 15,047 ton standard displacement. The gun is useful, but your PoD may be limited.
What's your PoD in particular? In OTL, the Navy considered multiple times (26 and 29) refitting the Tennessee class (and maybe the Pennsylvania class) cruisers that remained, along with swapping out the engines for a turbine set the Ranger used, reshaping the bow, adding additional torpedo protection, and reworking the armament to make them useful once more. The 10" was nice, but by the late 1920s, the triple 8"/55 that the Pensacola was using was also considered for replacing the main armament.
For this monitor to be especially useful, you'd need to up the gunnage to a 12" gun set on that displacement, I fear. The 10"/40 Mk 3 was already an antique by the post-war period, and was rapidly losing performance advantage to the 8"/55. The Navy viewed the triple 8"/55 and the double 10"/40 as two guns that filled the same role. And, if that's the case, a pure cruiser might be better than an undergunned monitor.
So, I'd suggest going with a 12"/45 Mk 5/6 that should also be scrapped at this same point in time. This gives you the caliber advantage that a monitor needs and differentiating it from being a slower, more shallowly drafted Tennessee.
Just to point out, I've actually been working on an armored aviation cruiser for the late teens/early 20s that uses an evolved Mk 4 10"/48 gun system. Overall has a 14,306 ton light displacement, and a 15,047 ton standard displacement. The gun is useful, but your PoD may be limited.
What's your PoD in particular? In OTL, the Navy considered multiple times (26 and 29) refitting the Tennessee class (and maybe the Pennsylvania class) cruisers that remained, along with swapping out the engines for a turbine set the Ranger used, reshaping the bow, adding additional torpedo protection, and reworking the armament to make them useful once more. The 10" was nice, but by the late 1920s, the triple 8"/55 that the Pensacola was using was also considered for replacing the main armament.
For this monitor to be especially useful, you'd need to up the gunnage to a 12" gun set on that displacement, I fear. The 10"/40 Mk 3 was already an antique by the post-war period, and was rapidly losing performance advantage to the 8"/55. The Navy viewed the triple 8"/55 and the double 10"/40 as two guns that filled the same role. And, if that's the case, a pure cruiser might be better than an undergunned monitor.
So, I'd suggest going with a 12"/45 Mk 5/6 that should also be scrapped at this same point in time. This gives you the caliber advantage that a monitor needs and differentiating it from being a slower, more shallowly drafted Tennessee.
Fair enough. It will have to be political differences that make the change, in the end. I've been working with a 1915/1916 PoD, so your tolerances can be a lot wider.
Sorry for the double post. Crossposting some work I was doing in another thread.
EDIT: Since I was so excited to simply put up a drawing, let me elaborate on the PoD. During the design process for the Omaha, the design is altered to a similar variant of the smaller scouts encouraged by Mr. Bates, one of the civilians on the preliminary design team. This smaller Omaha shares enough characteristics with destroyers that it is effectively treated like one, and the scouts are put into production much more quickly.
These designs OTL were S-584-111, S-584-112, S-584-113, and S-584-115.
Their flaws are recognized much more quickly OTL, especially their poor aviation performance, and so to address these concerns a larger scout design was sought. Simultaneously, the design philosophy of the board shifted towards Admiral Sim's philosophy of compensating for any deficiency in design by increasing displacement, not by sacrificing armor, speed, or gunnery. As such, BuOrd redesigns the South Dakota/Lexingtons to be a single vessel more inline with scheme D of the alterations proposed OTL (rather than scheme B), basically creating a fast battleship. (This is all based on BuOrd recognizing the Hood as a revolution in battleship design akin to the Dreadnought, rather than ignoring it because to give in would mean the entire US fleet was obsolete).
To compensate, the Colorado class was cancelled (save for Maryland, which was laid down in 1917, compared to the others) and the South Dakotas were placed under construction. To help assist funding, the older armored cruisers and battleships began to be scrapped before the WNT.
The inability of the Omahas creates the need for a ship with better aviation, and the change to make a fast battleship in 1918/1919 eliminates the Lexington and with it the prospect for two ships with partially overlapping missions. The first of these Augusta armored cruisers is launched in 21, and I imagine the first South Dakota would end up being launched in 1922.
The modification to the WNT to account for the Augustas would consist of a secondary class for armored cruisers, with a tonnage limit of ships from 10-12.5k tons being counted under it. Ships with major aviation facilities (defined as carrying 6 planes or more as a standard design complement and not possessing a landing deck, as then it would become a carrier) are given a 2.5k ton allowance. These ships are allowed to use up to 10" armament (the 9.2" for the British, or the 10" Vickers the Japanese have) while also using the same ratio among the powers. A total tonnage limit is also allotted (up to 120k tons of these classes of ships for the US/British, 72k tons for the Japanese, etc). This keeps the British Hawkins from being classified among these cruisers while preventing any battlecruiser as designed before the treaty to be made under these guidelines.
I had a short timeline up with it, but I have not addressed these changes (originally, I had the Lexington and South Dakota still being built, etc, but definitely needs to be addressed), but not much at all. This is more a mental exercise on how to make the 10" gun survive than anything.
Augusta, United States Armored Scout Cruiser laid down 1920
Displacement:
14,306 t light; 15,047 t standard; 15,898 t normal; 16,579 t full load
Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(686.00 ft / 681.50 ft) x 72.00 ft x (21.00 / 21.70 ft)
(209.09 m / 207.72 m) x 21.95 m x (6.40 / 6.61 m)
Armament:
8 - 10.00" / 254 mm 52.0 cal guns - 533.92lbs / 242.18kg shells, 150 per gun
Breech loading guns in turret on barbette mounts, 1921 Model
4 x Twin mounts on centreline, evenly spread
12 - 5.00" / 127 mm 51.0 cal guns - 66.47lbs / 30.15kg shells, 150 per gun
Breech loading guns in deck mount, 1911 Model
1 x Single mount on sides amidships
Weight of broadside 5,069 lbs / 2,299 kg
Main Torpedoes
6 - 21.0" / 533 mm, 21.00 ft / 6.40 m torpedoes - 1.362 t each, 8.172 t total
In 2 sets of deck mounted side rotating tubes
Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 5.00" / 127 mm 400.00 ft / 121.92 m 12.50 ft / 3.81 m
Ends: 0.75" / 19 mm 281.50 ft / 85.80 m 12.50 ft / 3.81 m
Main Belt covers 90 % of normal length
Main belt does not fully cover magazines and engineering spaces
- Torpedo Bulkhead - Strengthened structural bulkheads:
2.50" / 64 mm 400.00 ft / 121.92 m 12.50 ft / 3.81 m
Beam between torpedo bulkheads 68.00 ft / 20.73 m
- Hull void:
3.00" / 76 mm 400.00 ft / 121.92 m 10.00 ft / 3.05 m
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 2.50" / 64 mm 2.00" / 51 mm 2.00" / 51 mm
- Armoured deck - single deck:
For and Aft decks: 2.50" / 64 mm
- Conning towers: Forward 1.25" / 32 mm, Aft 1.25" / 32 mm
Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 110,000 shp / 82,060 Kw = 32.05 kts
Range 10,000nm at 10.00 kts
Bunker at max displacement = 1,532 tons
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
15,432 lbs / 7,000 Kg = 30.9 x 10.0 " / 254 mm shells or 2.1 torpedoes
Stability (Unstable if below 1.00): 1.10
Metacentric height 3.7 ft / 1.1 m
Roll period: 15.8 seconds
Steadiness - As gun platform (Average = 50 %): 75 %
- Recoil effect (Restricted arc if above 1.00): 0.67
Seaboat quality (Average = 1.00): 1.06
Hull form characteristics:
Hull has rise forward of midbreak,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0.540 / 0.545
Length to Beam Ratio: 9.47 : 1
'Natural speed' for length: 26.11 kts
Power going to wave formation at top speed: 54 %
Trim (Max stability = 0, Max steadiness = 100): 71
Bow angle (Positive = bow angles forward): 8.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 12.00 %, 32.00 ft / 9.75 m, 28.00 ft / 8.53 m
- Forward deck: 21.00 %, 28.00 ft / 8.53 m, 24.00 ft / 7.32 m
- Aft deck: 48.00 %, 16.00 ft / 4.88 m, 16.00 ft / 4.88 m
- Quarter deck: 19.00 %, 16.00 ft / 4.88 m, 16.00 ft / 4.88 m
- Average freeboard: 19.73 ft / 6.01 m
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 114.2 %
- Above water (accommodation/working, high = better): 171.8 %
Waterplane Area: 33,925 Square feet or 3,152 Square metres
Displacement factor (Displacement / loading): 96 %
Structure weight / hull surface area: 126 lbs/sq ft or 615 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.99
- Longitudinal: 1.05
- Overall: 1.00
Cramped machinery, storage, compartmentation space
Excellent accommodation and workspace room
Ship has slow, easy roll, a good, steady gun platform
360 tons of additional weight is surplus for both aviation facilities and for any additional AA guns that are to be mounted.
Ship Sideview Sketch (Ignore goof, they are 52 caliber guns, not 48)
Hanger Focus (Earlier version. Ignore variable level catapults/cranes. All cranes are the taller version in final, and all catapults are deck level)
Aeromarine AMC (OTL Aircraft, included for posterity)
Aeromarine AS-3 (Would basically be a center float variant of the AS-2, shown below. AS-2 is OTL, AS-3 is not)
I just think monitors are cheap and fast building expedients to get more shore bombardment guns afloat, in peace time the admirals will spend limited cash on long term more powerful and flexible battleships. In OTL nobody apart from small poor limited coastal navy's who could not afford real BBs bought anything like monitors or coastal defence like outside wartime.
If the powers don't trust each other they will spend on capital ships and the treaties would quickly break down if anybody else outside build anything dangerous.
That entiely depends on what you want your ship to do.
Older and larger ships have (a) higher fuel and maintenance costs and (b) larger crew requirements.
They also have (c) a deeper draught.
If you want a coastal bombardment type vessel, then a shallower draught vessel is much better (Gets closer). As for running costs, I can see why a cheaper to run ship is more advantagous (sp) in several cases, even though you have to build it. As another has said the main time and cost of a new warship are the guns and armour. If you can reuse those items off an older ship, you actually have a fairly cheap ship (All things considered) to build. You can also build it quicker as it takes a few years to produce the armour and guns (Usually they are ordered 1 to 2 years before the hull).
That misses the point that in peace time ships in limited reserve use like the old BB could be kept in (like the old PD pre WWI) cost very little even compared to a new build using old parts.
++Snip++
That misses the point that in peace time ships in limited reserve use like the old BB could be kept in (like the old PD pre WWI) cost very little even compared to a new build using old parts.
That is true, but as an observation: In peacetime far away ports also need guard ships.
It is also true that most places used gunboats or older destroyers etc, but in some cases (For example China due to their war with Japan or an out of the way port with limited shore-side facilities) a larger ship may be benificial in that role.
Afraid not, it was just something I was playing around with trying to workout an Idea. All I can say is it started out as HMS Erebus. I stretched the hull and gave it a slightly deeper (but probably not enough) draught.
