Hello everyone
That class needed a redraw anyway...
Caithreim, Thiarian Navy Conlan-class Battleship
The history of this class started in the late 1920s. Thiaria's economy, which had experienced a recession during the mid-1920s (the 'roaring twenties' were something that happened to other people), continued to behave against the global trend; fueled (literally) by newly found oil deposits, it went into a boom phase just as the rest of the world plunged into the great depression. This meant they were able to spend big time just as everyone else needed to be austere. To prevent an unchecked building spree, they were invited to the London naval arms reduction conference in 1930. The result seemed like a big diplomatic victory - aircraft carriers were no longer outlawed, the 20.000ts size limit on battleships was lifted and the normal 35.000ts limit now applied, and total battleship tonnage was set to 131.250ts. The limit however fell way short of Thiaria's ambitious plan to construct a navy the same size as France's, which seemed quite feasible in the current economic situation, and was not as enthusiastically received by the military and the political right wing as might have been expected. Moreover, Thiaria’s admission to the naval club was subject to special restrictions: they had to agree to a main gun caliber limit of 356mm for new battleship construction, which the British wanted to establish as a general limit for everyone; they had threatened to veto Thiaria’s new tonnage limit otherwise. The current government - a grand coalition between National Democrats (Daonlathas Naisiunta) and Labour (Lucht Oibhre) - was determined not to disappoint international goodwill and strictly ruled against any attempt to cheat concerning displacement or gunnery.
Requirements were 30 knots speed, 10.000 nm range at 15 knots, high freeboard to operate in any weather, dual-purpose secondary guns to keep down weight, and accommodation for six reconnaissance and spotting planes, which were considered essential for raiding. The design featured a long, slim, flush-decked hull with a bow bulb and a transom stern. Their hull was the most slender of all treaty-era battleships, featuring a length/width ratio of about 8,5. With a forward freeboard of nine meters and a half, averaging seven meters over most of the ship's length, and considerable flare at the steeply raked bow, they were very good seaboats and dry forward even under South Atlantic conditions. Their narrow beam however made them somewhat less steady than desired; the Thiarians needed some time to develop a fire control routine that could cope, and their gunnery was not really rated first class till mid-1942.Superstructure arrangement featured two widely spaced funnels, a pyramidal bridge structure and two pole masts, the forward one stepped against the bridge, and the aft one against the rear funnel. They displaced 34.990 tons standard (40.060 tons full load, 42.470 tons emergency war load). As Thiaria had ample deep-water ports, there had been no design restrictions on draught, which was a whooping 9,85 meters at full load. One point of criticism was the ship’s ponderous silhouette, especially when viewed over the bow, due to the massive hangars, which made identification easy for the enemy. On the plus side, they were spacious and had comfortable accommodation for their crew of 1.350 (wartime maximum 1.750).
Machinery was a 135.000hp three-shaft plant, with emphasis placed on sturdiness, reliability and accessibility over sheer power. The center shaft was served by one 45.000hp turbine set with four boilers forming a self-contained unit, while the wing shafts were coupled to two identical sets which were arranged en echelon (Starboard turbines forward, port boilers forward). Each shaft had its own rudder to minimize the effects of underwater hits in this location, and piping was provided for cross-feeding the center shaft from the flank unit boilers in case of heavy damage. On trials, the 30-knot design speed was secured at 95% power; at designed hp, they made 30,35 knots, and on max power trials, they touched 31,5 knots with 155.000 shp. They could steam at 27 knots at 2/3 power and sustain 25 knots at half power. With the center shaft only, they could sustain 20 knots (22 knots max). Range was 10.000nm at 15 knots; trial fuel consumption was according to expectations. At 20 knots travel speed, range nearly halved to 5.500 nm; traveling leisurely at 12 knots, it increased to 16.000 nm. Electrical power was provided by six turbo-generators (two per main machinery unit) and four auxiliary diesel generators placed in separate compartments, one in front of the forward main machinery unit, the other between them). Leak pump capacity was 5.000 tons per hour.
Being designed as raiders, their armour scheme emphasized protection against plunging shells and bombs. The main belt of 310mm thickness was external and inclined 15° inward; it was topped by an upper strake of 145mm. A layer of 80mm protected the waterline forward and aft of the citatel, protecting it from anything below 152mm shells, another requirement for raiding missions where loss of speed by flooding forward from a destroyer shell could mean a mission kill. Horizontal protection was among the strongest ever installed on a capital ship up to that time. The main armoured deck was 140mm above magazines and 115mm above machinery, topped by a 35mm upper deck to initiate bomb fuzes and de-cap shells striking at oblique angles. Forward and aft, the armoured deck was extended along the upper rim of the belt at a thickness of 45mm, with 180mm boxes over the rudder machinery. The 45mm torpedo bulkheads were 4m from the outer hull at the broadest part of the ship and built into the hull structure to save weight; protective space comprised two void compartments (with the option to fill them with water for counterflooding), interchanging with two compartments filled with ebonite mousse for reserve buoyancy, mirroring French practice. Its width was generally considered insufficient against 533mm and larger fish; Conlan was once torpedoed to near disastrous effect, but her tight compartmentation proved sufficient to contain flooding. Caithreim just got lucky.
Main armament consisted of three turrets mounting three individually sleeved 340mm L/50 guns each, with an elevation of 35°. The turrets were considered relatively cramped in service, and the designed RoF of 2 rounds per minute was not attained in practice (although at the typical engagement ranges she had to fight, more than one round per minute was not possible anyway). As completed, the guns fired the standard 600kg APC shell, but magazines and hoists were designed for the new 720kg extra-long super-heavy shell; the latter became available in early 1940. Two main artillery directors were provided. In service, the main gunnery of these ships was very satisfactory. Long-range accuracy in particular was considered first class, especially with the super-heavy shells, due to the relatively limited muzzle velocity of 760 m/s, compared with 850 m/s for the old shell. For the secondary armament, the Thiarians followed the French lead towards DP guns, using the same caliber. Their 130mm L/45 pieces were in use on contemporary destroyers already (although only in LA mounts) and had a good reputation. They had much better RoF and more carefully designed turrets than their French counterparts, with 85° elevation and higher training speeds; they were very good against ships and reasonably good against air targets. Although better antisurface weapons, they were inferior to the US 127mm L/38 as AA guns, however. The entire DP battery of six two-gun demi-turrets was concentrated aft in three superfiring pairs, one on the centerline and two as far outboard as possible, allowing the upper wing turrets to fire nearly ahead (5° off-axis). This arrangement gave the specified broadside of eight guns at very modest weight, although the low total number of guns was criticized in the Thiarian press. Conlan and Caithreim had, in fact, the weakest secondary batteries of all capital ships of the 1930s. The DP battery was served by three directors – two at the rear end of the bridge pyramid, one aft on the centerline, fully covering the DP gun’s arcs. To keep down weight, the DP directors were entirely unprotected. As flimsy as the DP battery was, their intermediate caliber flak battery was exceptionally powerful. It consisted of 32 fully automatic 37mm L/70 barrels in eight hemispherical self-contained, gas-tight quad turrets with 85° elevation, four forward and four aft, in superfiring pairs. The guns were jointly developed with France and had a tremendous RoF of 180 rounds per minute, which was governed down to 150, that being the maximum their barrels could stand. Barrel life still was only half the figure attained by US built 40mm Bofors (6.000 rounds rather than 12.000), but in exchange for that, these guns offered somewhat better range and accuracy than the Bofors. The mounts were equipped with internal hoists directly connecting them to their own magazines, ensuring a steady supply of shells and enabling them to keep up their RoF even in prolonged engagements. In service, the guns proved deadly, especially as each group of two was coupled to its own radar-guided director. Thiarian capital ships repeatedly repulsed intense air attacks and scored several dozen kills, two thirds of them with the 37mm L/70. The flak battery was completed by eight quad 13mm MG mounts, four on top of the hangar and four aft alongside the aft main gun director. Six searchlights were provided, carefully arranged for all-round coverage. Their employment as raiders required torpedoes; two quad 559mm tubes with a full set of reloads were provided on the weather deck amidships. Due to the importance of scouting and long-range spotting, no less than six aircraft could be carried, four in two hangars alongside the forefunnel, and the other two on platforms abaft the catapults. The hangars had large shutters for ventilation and could be accessed by platforms extending to the catapult mounts; the platforms were equipped with rails upon which the airplanes could be moved to the catapults. Most of the boat complement was stowed amidships between the aviation handling platforms and served by two heavy-duty cranes mounted far outboard at the rear end of the hangars. The boat complement was relatively austere; newer Thiarian ships relied on large numbers of rescue rafts in cases of distress.
The first ship was approved in the 1933 budget and laid down in February 1935 at the Abernenui Naval Yard. Deviating from the usual Thiarian practice of naming battleships for famous historic personalities, it received the abstract name LT Conlan (Endeavour). Construction took slightly longer than four years, and she was ready for service in April 1939. Her sister, funded by the same budget, was laid down in July 1935 at the Nuatearman Naval Yard and received the name LT Caithreim (Triumph). Building her took somewhat longer, and she was commissioned in February 1940. Conlan was fully worked up when Thiaria entered the war in January 1940, while Caithreim was undergoing acceptance trials. After missing the initial engagements of the war, Caithreim had her combat debut in the battle of Poncportan in early June, after the British had withdrawn many assets for the battle of Norway. Unlike Conlan, she was already equipped with main artillery fire-control radar and the new 720-kg shell, doing most of the damage that sunk the big British battlecruiser HMS Howe. It was the first entry in the war record of the most successful capital ship on either side of that conflict. Caithreim would engage in nine major engagements and participate in the sinking of four capital ships belonging to four different navies, plus an escort carrier, a cruiser, three destroyers, and 22 merchants. She traveled nearly two hundred thousand miles, ranging deep into the Indian Ocean several times, twice reaching the equator in the central Atlantic and once crossing it in the eastern Pacific during the famous Panama raid. Her most remarkable achievement however was losing only 85 crewmembers over the whole course of the war (in stark contrast to her sister, who was regularly shot up beyond recognition). Apart from HMS Howe, Caithreim’s victims included the Brazilian battleship Sao Jorge da Mina, the US battlecruiser USS President, and – when she served with the co-belligerent squadron sent to the Pacific after Thiaria’s swap of sides – the Japanese battlecruiser Kongo. The Americans were so impressed with Caithreim’s performance that they allowed her presence at the Japanese surrender in Tokyo Bay. After the war, she belonged to the Third of the Axis fleet claimed by the Soviets; she reached Archangelsk in 1948, to serve for another twenty years with the Soviet Navy, nearly coming to blows with the US during the Cuban crisis. She was as popular in the Soviet navy as in Thiaria’s; although her design more properly placed her in the category of early-1930s battlecruisers with subpar gunnery (like the French Dunkerque, the German Gneisenau and the Italian dreadnought rebuilds), she was always considered a full-blown treaty battleship of well-balanced properties, repeatedly trading blows with ships rated much superior on paper, and surviving to tell about it. After her final refit in 1967 – 1969, when she received Osa-M SAMs and new radars and electronics, the Soviets did not re-commission her, because her large crew was needed for the new aircraft carriers. Leonid Brezhnev handed her back to the Thiarians in 1970 as a goodwill gesture; she was never recommissioned, however, and in the 1980s became a museum ship in Thiaria's largest maritime museum at Nuatearman. She remained on the Navy's reserve list, from which she was not struck before 1992. Over the years, she featured in about a dozen movies, some of which show her moving under her own power and firing her heavy guns; the latter are sealed these days, but her engines are reported to be still operable, to the lasting fury of the comptroller of the Navy, who has to spend twice as much money on the ship’s upkeep than comes in through selling admission tickets to tourists.
The drawing shows LT Caithreim in December 1942 during a raid against a Commonwealth convoy south of Madagaskar, which succeeded in sinking ten merchants, a Recherchean light cruiser, two escort destroyers and a corvette; one of the destroyers and four Merchants were credited to Caithreim’s weapons. It was the last mission for which she wore a raider blue livery; the deck planks were also painted blue, but the anti-slip coating on the shelter deck and higher levels remained gray. Three white bars across the forecastle as visual IFF (usually painted over for raids) had been retained, because the carrier Realtbhuion accompanied the raid. By that time, Caithreim was fitted with a first-generation air surveillance radar (80cm wavelength) on the mainmast, whilst the foremast carried a surface search radar (recently upgraded to a second-generation 5cm wavelength set), an IFF interrogator and transmitter, a radar jammer, and HF/DF. All directors (for main battery, DP guns and 37mm AA guns) were fitted with first-generation fire control radars. The quad 13mm HMGs had been replaced by twin 20mm Hispano-Atlantach autocannon, and two more mounts had been added on top of the hangar. Two of Caithreim’s six airplanes are shown: An Aerelar M2E Caracara spotter plane with folded wings on its readiness spot and a CSCA M6S Fulmaire reconnaissance aircraft on the catapult. Three of each type were carried (the hangar accepted one of each type or two Caracaras, but not two Fulmaires). The catapult would swivel outwards by 45° to launch the aircraft.
For what it’s worth, this is what Springsharp thinks of the design:
Conlan, Thiaria battleship laid down 1935
Displacement:
33.183 t light; 34.966 t standard; 37.799 t normal; 40.066 t full load
Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(816,12 ft / 791,01 ft) x 93,50 ft x (30,84 / 32,30 ft)
(248,75 m / 241,10 m) x 28,50 m x (9,40 / 9,84 m)
Armament:
9 - 13,39" / 340 mm 50,0 cal guns - 1.587,33lbs / 720,00kg shells, 90 per gun
Breech loading guns in turret on barbette mounts, 1935 Model
3 x 3-gun mounts on centreline ends, majority forward
1 raised mount - superfiring
12 - 5,12" / 130 mm 45,0 cal guns - 67,62lbs / 30,67kg shells, 450 per gun
Dual purpose guns in deck and hoist mounts, 1935 Model
4 x 2-gun mounts on sides, aft evenly spread
2 raised mounts - superfiring
2 x 2-gun mounts on centreline, aft deck aft
1 raised mount - superfiring
32 - 1,46" / 37,0 mm 70,0 cal guns - 1,72lbs / 0,78kg shells, 4.000 per gun
Anti-air guns in deck and hoist mounts, 1935 Model
4 x 2 row quad mounts on sides, forward deck forward
2 raised mounts - superfiring
4 x 2 row quad mounts on sides, aft deck aft
2 raised mounts - superfiring
32 - 0,51" / 13,0 mm 80,0 cal guns - 0,09lbs / 0,04kg shells, 12.000 per gun
Machine guns in deck mounts, 1935 Model
8 x Quad mounts on sides, evenly spread
Weight of broadside 15.141 lbs / 6.868 kg
Main Torpedoes
8 - 21,7" / 550 mm, 22,97 ft / 7,00 m torpedoes - 1,624 t each, 12,993 t total
In 2 sets of deck mounted side rotating tubes
Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 12,2" / 310 mm 446,19 ft / 136,00 m 11,52 ft / 3,51 m
Ends: 2,36" / 60 mm 344,49 ft / 105,00 m 11,52 ft / 3,51 m
Upper: 6,50" / 165 mm 446,19 ft / 136,00 m 8,01 ft / 2,44 m
Main Belt covers 87% of normal length
Main Belt inclined 15,00 degrees (positive = in)
- Torpedo Bulkhead - Strengthened structural bulkheads:
1,57" / 40 mm 446,19 ft / 136,00 m 28,84 ft / 8,79 m
Beam between torpedo bulkheads 70,54 ft / 21,50 m
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main:14,6" / 370 mm 9,45" / 240 mm 11,8" / 300 mm
2nd: 1,97" / 50 mm 0,79" / 20 mm 0,79" / 20 mm
3rd: 0,79" / 20 mm 0,79" / 20 mm -
- Armoured deck - single deck:
For and Aft decks: 6,10" / 155 mm
Forecastle: 2,36" / 60 mm Quarter deck: 4,72" / 120 mm
- Conning towers: Forward 14,57" / 370 mm, Aft 0,00" / 0 mm
Machinery:
Oil fired boilers, steam turbines,
Geared drive, 3 shafts, 135.000 shp / 100.710 Kw = 30,36 kts
Range 10.000nm at 15,00 kts
Bunker at max displacement = 5.100 tons
Complement:
1.355 - 1.762
Cost:
£15,117 million / $60,468 million
Distribution of weights at normal displacement:
Armament: 2.967 tons, 7,8%
- Guns: 2.941 tons, 7,8%
- Weapons: 26 tons, 0,1%
Armour: 13.372 tons, 35,4%
- Belts: 4.060 tons, 10,7%
- Torpedo bulkhead: 750 tons, 2,0%
- Armament: 2.488 tons, 6,6%
- Armour Deck: 5.721 tons, 15,1%
- Conning Tower: 353 tons, 0,9%
Machinery: 3.835 tons, 10,1%
Hull, fittings & equipment: 12.808 tons, 33,9%
Fuel, ammunition & stores: 4.617 tons, 12,2%
Miscellaneous weights: 200 tons, 0,5%
- Above deck: 200 tons
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
58.929 lbs / 26.730 Kg = 49,1 x 13,4 " / 340 mm shells or 6,8 torpedoes
Stability (Unstable if below 1.00): 1,07
Metacentric height 5,1 ft / 1,6 m
Roll period: 17,4 seconds
Steadiness- As gun platform (Average = 50 %): 59 %
- Recoil effect (Restricted arc if above 1.00): 0,90
Seaboat quality (Average = 1.00): 1,19
Hull form characteristics:
Hull has a flush deck, a straight bulbous bow and small transom stern
Block coefficient (normal/deep): 0,580 / 0,587
Length to Beam Ratio: 8,46 : 1
'Natural speed' for length: 30,25 kts
Power going to wave formation at top speed: 51 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 35,00 degrees
Stern overhang: 3,28 ft / 1,00 m
Freeboard (% = length of deck as a percentage of waterline length):
- Forecastle: 20,00%, 31,17 ft / 9,50 m, 23,79 ft / 7,25 m
- Forward deck: 30,00%, 23,79 ft / 7,25 m, 22,97 ft / 7,00 m
- Aft deck: 35,00%, 22,97 ft / 7,00 m, 22,97 ft / 7,00 m
- Quarter deck: 15,00%, 22,97 ft / 7,00 m, 24,28 ft / 7,40 m
- Average freeboard: 23,94 ft / 7,30 m
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 85,7%
- Above water (accommodation/working, high = better): 175,3%
Waterplane Area: 54.422 Square feet or 5.056 Square metres
Displacement factor (Displacement / loading): 113%
Structure weight / hull surface area: 190 lbs/sq ft or 928 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0,97
- Longitudinal: 1,29
- Overall: 1,00
Adequate machinery, storage, compartmentation space
Excellent accommodation and workspace room
Cheers
GD