Shipbucket

Cool drawing of a modernized Yorktown class carrier. I always thought it was a shame they couldn't save the Enterprise from the scrap yard.

Command cruiser ARS Scarlette Bay



The Iris-class was the last pre-WW heavy cruiser class built by the Antaran Navy, designed to be the most powerful cruiser of its time, at the cost of violating the ENT by over 3500 tonnes. However due to the political state of Aemore in 1340, no nation paid any attention to the violation. The basis for the design was to improve the firepower of the previous Alexandria with as little compromise whatsoever, thus Iris had a 4xIII 203mm/55 gun layout, with two additional twin 127mm/45s on the forward deck. She did however have a thinner 127mm belt, but was faster during trials - going 34.1 knots on average. Iris's broadside firepower had such a kick that it was advised for captains to fire half-salvos to reduce the recoil.

After the war, Port Reid and Iris were selected for missile conversions in the late 50s, while Monroe City and Scarlette Bay were chosen to be converted to command cruisers. By 1370, these command cruisers had been pressed into the role of ASW flagship.

Specifications

Tonnage - 13 500 tonnes standard
Speed - 34.1 knots
Range - 8000nm at 14 knots
Main battery - 4xIII 203mm/55 (as built)
Secondary battery - 5xII 127mm/45 (as built)
Armor - 127mm belt, 76mm decks, 50mm secondary turrets, 178mm MB turret face, 76mm MB turret sides, 203mm barbettes, 127mm conning tower

Ships in class

Iris - Scrapped, 1382
Port Reid - Scrapped, 1382
Monroe City - Sunk in missile tests, 1372
Scarlette Bay - Scrapped, 1384

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Didn't put as much detail as I wanted into the top view but I've run low and time/energy as I started taking graduate courses.

Boise-class ASW Cruiser

With the signing of the London Naval Limitation Treaty in 1936 the US had to decide what type of cruisers they would be building. The General Board looked at several alternatives, but in the end decided to build a leader for destroyer flotillas. The leaders that were being replaced were armed with 6-inch guns, so the initial designs followed those parameters. Eventually to get anti-aircraft defense the Board decided to go with a newly designed quadruple dual-purpose 5" mount.

Looking at operations during WWI, aircraft for keeping submarines submerged to allow the passage of forces around a submarine threat. With that in mind, a large aircraft complement was desired, and designers managed to create enough space for eight aircraft in a hanger. They also wanted speed high enough to operate directly with the destroyers in the flotilla. This made for a long hull to accommodate all of the desired characteristics.

Boise was completed in 1940 and immediately assigned to the Atlantic Fleet where she operated as a part of Neutrality Patrol. On the outbreak of war, she operated off of the US East Coast protecting shipping in the area. Although her aircraft were able to force submarines under the surface, they didn't sink any. Early in 1942 she entered Boston NSY for upgrades including radar and OS2U Kingfisher aircraft. New tactics combining her aircraft with assigned destroyers allowed for successful operations in the Gulf of Mexico protecting tankers sailing from Aruba.

Later operations included protection of the invasion beaches at Casablanca and later off Sicily before moving off Normandy where her large flag facilities helped coordinate the operations sealing the southern entrance to the English Channel. Following the successful landings, she was proceeding back to the US when she took a torpedo in her after engine room. The length of her repairs prevented her from taking part in Pacific operations.







Boise-class as built
Displacement: 7,634 t light; 7,951 t standard; 9,065 t normal; 9,956 t full load

Armament:
8 - 5.0” /38 cal Mk. 12 dual-purpose guns in deck and hoist mounts
55.18lbs shells, 400 per gun
2 x 4-gun mounts on centerline, forward evenly spread
1 raised mount

32 - 1.1”/75 cal Mk. 2 anti-aircraft guns in deck mounts
0.93lbs shells, 2,500 per gun
4 x Quad mounts on sides, forward deck aft
4 raised mounts
4 x Quad mounts on centreline, aft evenly spread
4 double raised mounts

4 - 0.5”/90 cal M2 machine guns in deck mounts
0.05lbs shells, 3,000 per gun
4 x Single mounts on centerline, forward evenly spread
4 double raised mounts

8 - Mk. 15 torpedoes in 2 sets of deck mounted side rotating tubes

2 – Stern depth charge racks with Mk. 6 Depth Charges + 48 reloads

Armor
- Belts: 2.25”
- Decks: 1.25”
- Quarterdeck: 0.75”
- Main: 2.50”

Machinery
Oil fired boilers, steam turbines, geared drive
2 shafts, 90,000 shp = 34.04 kts
Range 9,100nm at 15.00 kts
Bunker at max displacement = 2,005 tons

(slightly old drawing)
I didn't draw anything new, since the Caledonia navy have this:

Hull mounted active/passive sonar
towed sonar
Nulka and other type of decoys

Armarment:
1 x 5" cannon DP
2 x 40mm cannon DP
1 x Mk 29 GMLS for Sea Sparrow
2 x triple ASuW missile launcher (missile is not with the ship on this drawing)
2 x mini rocket ASW charges thrower
2 x triple 324mm torpedo tubes (ASW)
1 x improved depth chargers launcher
1 x ASW GMLS, with magazine. (Firing a rocket guided torpedo carrier out to a designated target area, range between 10-80km, depending on cargo) (can also carry depth charges) (Fire 2 rockets within seconds of each other before need of a reload from magazine)

Aviation: Hangar for 1 Lynx helicopter in a ASW role.

Ontario - class Guided Missile Cruiser, Helicopter



Displacement: 11,000 tons (standard), 12,800 tons (full load)
Length: 181.4 m (595 ft)
Beam: 23.9 m (78.5 ft)
Draught: 9.9 m (32.5 ft) [incl. sonar dome]
Propulsion: 4× Babcock & Wilcox boilers, 4× steam turbines (2× main turbines, 2× cruising turbines, paired with Synchro-Self-Shifting [SSS] clutch) driving 2× shafts, 60,000 hp
Speed: 29 knots
Range: 6,800 nm (12,600 km; 7,800 mi) at 16 knots
Complement: 495
Sensors and processing systems: 1× AN/SPS-48 (3D air search), 1× AN/SPS-40 (2D air search), 1× AN/SPQ-2D (low level air/surface search), 1× Sperry Mk.127E (navigation), 2× AN/SPG-55B (Terrier/Standard fire control), 2× AN/SPG-48 (on-mount fire control for Mk. 33 twin guns), 2× WM-20 (Sea Sparrow fire control), 1× AN/SQS-505 (hull-mounted sonar), 1× AN/SQS-505 (variable-depth sonar)
Electronic warfare: AN/WLR-1C ECM system
Countermeasures/decoys: 4× Corvus chaff launcher, Prairie-Masker noise reduction system
Armament: 1× Mk. 10 Mod 8 GMLS (40× RIM-67A Standard ER, 20x RUR-5 ASROC), 1× Mk. III Canadian Sea Sparrow missile system (32× RIM-7E Sea Sparrow), 2× 3”/50 calibre Mk. 33 twin guns, 2× Mk. 32 SVTT (Mk. 46 Mod 2 torpedoes)
Aircraft carried: 8× CH-124A Sea King

Vessels in class:
CGH-33 HMCS Ontario (Laid down 11/07/1966, launched 30/07/1970, commissioned 17/04/1973, decommissioned 07/03/2005)
CGH-34 HMCS Quebec (Laid down 03/10/1966, launched 28/11/1970, commissioned 03/11/1973, decommissioned 20/06/2014)

During the early 1960s, the Royal Canadian Navy produced a series of design studies for so-called “heliporters”, otherwise known as helicopter-carrying destroyers; vessels that would be able to operate and maintain several anti-submarine helicopters and act as a mothership for escort fleets in the event of hostilities with the Soviet Union. One of these designs, PD-30, envisioned a 7,400-ton vessel capable of carrying eight Sea King helicopters, as well as being fitted with a variable-depth sonar and self-defence missile system. Interestingly, this design strongly resembles the French helicopter Jeanne d’Arc as she was originally designed with the Masurca surface-to-air missile system.

My thought process for this design was straightforward – what if Canada had cooperated with France to produce a class of vessels that were similar in design and based on similar operational requirements? My design drops the Mk. 13 GMLS + ASROC combo and instead fits a Mk. 10 GMLS which can carry both Standard ER and ASROC simultaneously. Additionally, leveraging technology development from the Iroquois – class destroyer programme, these cruisers are fitted with the Canadian Sea Sparrow missile system for self-defence. This class drops SPS-501 (based on the Dutch LW-03) in favour of SPS-40 to save topweight.

Two helicopter landing positions are provided, allowing two Sea Kings to take off or land simultaneously. The RCN had produced a study which found that based on a four helicopter cycle (one Sea King on task, a second on immediate standby, a third on serviceable backup and the fourth under maintenance), it would require a minimum of eight helicopters to keep at least two airborne at all times for a period of seven to ten days. A “beartrap”-type deck traversal system would be fitted to each landing position, allowing Sea Kings to be moved to and from the aircraft elevator, although in fair seas tugs would commonly be used for traversal in order to simplify operations.

Originally the RCN had wanted to build twelve such vessels, as per the Brock Report of 1961. This was later reduced to four vessels in the Maritime Force Programme of 1964. Although much reduced in size, these so-called “heliporters” would eventually evolve into the real-world Iroquois (DDH-280) class. In my alternate universe scenario, I’m imagining that two of these large helicopter cruisers, more like the original concepts, are built simultaneously to four DDH-280s. Because the RCN lacks experience designing such large warships, Canada collaborates closely with France on this project, building two vessels that turn out very much like the Jeanne d’Arc. Despite the collaboration, they still take much longer to build than originally planned and run far over budget, becoming a hot-button topic in the 1968 Canadian federal election. The government justifies the expenditure by highlighting the multi-purpose nature of the vessels; although originally designed for anti-submarine warfare, they are also capable of supporting the Canadian Army in UN peacekeeping missions.

In later years, the two vessels spend most of their time as training vessels, carrying containerized living quarters in their hangar bays for officer cadets in place of additional helicopters. HMCS Ontario is decommissioned early in 2005, being cannibalized for parts to keep her sister’s ageing steam powerplant in operation. HMCS Quebec is finally decommissioned in 2014 with the arrival of the newly built HMCS Vimy Ridge, the first of two Juan Carlo I – type amphibious warfare vessels.

Challenge Extension
Multiple people have expressed interest in an extension on the Shipbucket Discord server. I have therefore decided to extend the challenge by one week. It will now end on the Sunday the 14th of November at 23:59 (UTC-12). An updated countdown timer can be found at this link.

Koko - ASW Aircraft Carrier Tsugumi.

Last Kokoan evolution of the Shokaku class design, Tsugumi started her life as an anclosed-bow armored flight-deck carrier, laid down at Hoshiguma Navy Yard in January 1945. Still incomplete at the end of the war, her hull built only up to the lower hangar deck, she sat in her own slipway awaiting to be disposed off as surrendering terms dictated. Yet, the newly reformed postwar Koko Kaijou kept Tsugumi at the bottom of the list as the last carrier that had to be scrapped in the hope that restrictions had been somehow modified by the time it was her turn to go to the breakers.
This eventually happened when the Korean war broke out as the US decided to benefit from another Ally in the Pacific region. With restriction on fleet strength removed, Tsugumi was order to be completed again and her design modified with US assistance. She was launched in 1951 and commissioned by the end of 1953, although too late to see service in the Korean conflict.
Compared to the original design, the lower hangar was reduced in size and the upper hangar expanded, the two elevators serving them were also lengthened and widened (only the former for the forward elevator). The hurricane bow was widened, the flight deck strenghtened and its area vastly increased, more powerful hydraulic catapults installed. The planned armored flight deck was replaced by a 76mm upper hangar deck and a 25mm lower hangar deck, all other armor was omitted with the exception of magazine and underwater protection. The original planned armament of eight 100 and sixty-four 40mm guns was replaced by improved unshielded 100mm and nine twin US built 76mm pieces.
Upon commissioning she became Koko Kaijou's flagship, and served mainly as a training carrier before recieving a radar update in late 1955. After that she was designated as an anti-submarine warfare carrier, embarking twenty Grumman S2F-1 Trackers and sisteen Sikorsky HSS-1 Seabat helicopters, the latter for search and rescue operations in addition to ASW, plus eight Douglas A4D-2 Skyhawk fighters for reconnaissance and combat air patrol. By the end of the decade flight operations had become cumbersome on her axial flight deck, so when Sekirei was commissioned in 1958 Tsugumi was drydrocked and refitted with the addition of an angled deck. She served in her new configuration until retirement in 1981.



Tsugumi specifications as of 1958:

-Displacement: 29.112 t standard, 41.532 t full load
-Length, overall: 271,44m (891ft, 6'')
-Length, hull: 269,92m (886ft, 6'')
-Length, waterline: 261,39m (858ft, 6'')
-beam, maximum (3'' gun platforms): 45,36m (148ft, 11'')
-beam, waterline: 29,38m (96ft, 6'')
-mean draft: 9,6m (31ft, 7'')
-Machinery: 8x Oil firing boilers, 4x geared steam turbines, 200.000 shp, 4 shafts
-Speed: 33 kts
-Range: 9.700nm at 18 kts
-Armour: deck 76+25mm (3+1''), magazines 76mm (3''), torpedo bulkhead 51mm (2'', protective internal bulge 3m on each side)
-Armament: 8x 100mm/60 DP guns (4x2, 400rpg), 18x 76mm/50 Mk.27 (9x2, 1.500rpg)
-Electronics: AN/SPS-6 air search radar, AN/SPS-8A height finder, SG-6 surface and zenith search radar, SR-5 backup air search radar, AN/SPN-6 air search aircraft approach control radar, AN/SPN-8 aircraft approach control radar, AN/SPN-12 airspeed indicator, YE-2 aircraft homing beacon, Mark24 GFCS, Mark25 air FC radar (2x1), Mark56 mod-5 director, Mark35 air FC radar (3x1), URN-3 TACAN, URD-4 TACAN, AN/CPN-6 navigation surface reference, DBM-1 RDF (2x1), AN/URD-2 DF (2x1), 66AFJ IFF (2x1), 66015 TBS (2x1), SLR-2 ECM suite (3x1 AS-571, AS-570), AN/SPR-4 ECM suite (4x1 CAGW-66131, CAGW-66132), AN/URR-13 TED (16x1), TBA/TBM (11x1), XMTG/XMTR (13x1)
-Complement: 2854


Flight deck, hangar and airwing:

-Flight deck length: 266,42m (874ft, 11'')
-Flight deck width: 33,49m (109ft, 11'')
-Equipment: 14x arrestor wires, 4x crash barrers, 2x Type3-kai hydraulic aircraft catapults
-Upper hangar: 195,78m (643ft) long, 20,55/27,4m (67ft, 6''/90ft) wide, 5,2m (17ft, 1'') tall
-Lower hangar: 175,83m (577ft, 5'') long, 13,85/17,66m (45ft, 5''/58ft) wide, 4,9m (16ft, 1'') tall
-Forward elevator: 15,22 x 15,68m (50 x 51ft, 6'')
-Aft elevator: 15,22 x 14,15 m (50 x 46ft, 5'')
-Airwing: 44 (8x A4D-2 Skyhawk recon/CAP, 20x S2F-1 Tracker ASW, 16x HSS-1 Seabat ASW and SAR)

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My Worklist
Sources and documentations are the most welcome.

-Koko Kyouwakoku (Republic of Koko)
-Koko's carrier-based aircrafts of WWII
-Koko Kaiun Yuso Kaisha - KoKaYu Line (Koko AU spinoff)
-Koko - Civil Aviation

IJN Akagi, The super carrier turned ASW flagship


Originally commissioned in the early 1960s, as the Imperial Japanese navy's first nuclear super carrier design, the IJN Akagi would spend the majority of her life as the centrepiece of the imperial navy’s famous 1st carrier division, which has seen much success in the great Pacific War, with the Akagi's 1927 built predecessor, however by the late 70s newer and larger nuclear carriers had been commissioned, with Akagi and her sisters being relegated to lesser work, Akagi herself would undergo a refit in late 1984, emerging from the dry dock as a ASW flagship of truly immense proportions, in fact she was so large that she could operate a naval variant of the 4 engine land-based Q8K.
starting in 1985 Akagi would form the core of a brand new ASW Fleet, with her alongside and another order carrier refitted for ASW work, forming the centrepiece of this brand new ASW task force, throughout the first years of the Indian reunification conflict as it would later be known, she and her fleet did relatively little, with much of the conflict being primarily over land in central and northern India, however with the increased veracity of the German backed United Indian states, her and her fleet would quickly be called upon to provide any air cover that they could spare, with her fighter Squadron often being tasked with helping provide escort and air cover to northern Indian bombers targeting United Indian states military installations.
throughout the rest of the conflict her and her air group, would partake in many of the conflicts most notable operations, Akagi herself would end her service in the conflict, as a result of being heavily damaged by a United States Indian mass attack on her battle group on the 17th of October 1988, with many ships of the task force either being sunk or heavily damaged, Akagi herself would go on to see no more action during the conflict, spending several years in drydock undergoing repairs, she would continue to serve with the Imperial Japanese Navy until 2004, finally being decommissioned on the 22nd of January 2004, as of 2021 she is still awaiting disposal at Yokosuka naval Arsenal.

Specifications

Tonnage - 92,800 tonnes standard
Speed - 33 knots max
Range - Unlimited distance, 20-25 years
Gun Armament - 4x2 10cm Type 15
Missile Armament - 4x4 Dim-6 SAM
Armor - 20 cm aluminium armoured belt, 20 cm aluminium applied to all vital areas of the ship
Airwing - 44 (6 E20M-AWACS, 2 U6K-Utility Helicopter, 2 U6Ks-S&R, 15 A14M-Fighter / Attacker, 4 Q8K-ASW, 6-V9M-AAR, 5 U12S-ASW)


Ships in class: (laid down-launched-commissioned - fate)

Akagi 赤城 (CVN-1) 1956 - 1959 - 1961 - Decommissioned 2004
Shōkaku 翔鶴 (CVN-2) 1957 - 1960 - 1962 - Decommissioned 2007
Jun'yō 隼鷹 (CVN-3) 1959 - 1962 - 1963 - Decommissioned 2009

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Work list: 1. various pre-1900 Zipang ships 2. Some protected cruisers and other miscellaneous projects

Nothing particularly fancy from me, I hate top-views so only have a rudimentary one to do deck parks which I decided wasn't worth including.

Schemed as multi-role vessels, ostensibly as the flagships of anti-submarine hunter-killer groups but also capable of operating as sea control ships or commando carriers the Cerys-class of aviation support ships are the ultimate expression of the Banbhan "small" carrier philosophy.

Generally speaking a Cerys-class vessel alongside a Badhbh-class destroyer leader and two Gemstone-class air-defence destroyers would act as the hunter portion of the HK group with four ASW frigates of either the Tenacity or Danu classes providing the killers to be tasked off as required. As such the Cerys-class have substantial flag facilities suitable for an ASW commander and their staff.

Much like early CVF studies and Hyuga/Ise the Cerys-class feature a rear quarter mounted VLS for self-defence and ASROC, additionally they feature a heavy gun-based CIWS armament akin to the Cavour and Trieste.

IFEP was must for the design with the gast turbines mounted at hangar-deck level and the diesel generators on enclosed rafts allowing for self noise to be managed more efficiently than on a conventionally geared ship, there are masker belts astride the engine and machine spaces to further aid in managing noise, likewise the props are fixed-pitch.

Deck-edge lifts were considered but not progressed with due to the inherent weather limits they possess compared to inboard lifts, these are of the scissor variety with the wells being used to store aviation sundries.

Cerys-class Aviation Support Ship



General Specifications:
Displacement:31,500t Light, 36,400t Full Load
Length: 249.2m WL, 274.5m OA
Beam: 32.75m WL, 51.65m OA
Mean Draught:8.38m
Midsdhips Depth:26.8m
Propulsion:
- IFEP via 2x LM2500+G4 @34MWe ea. 4x CAT 16M32C @7.68MWe ea. 2x CAT C175 auxiliary service generators @2.5MWe ea.
- 2x fixed-pitch props with two auxiliary rim-driven propulsors capable of limp-home propulsion
Speed: 31.25kts deep and clean
Range + Endurance: 16,700km @ 15kts with supplies for 45 days
Complement: 470 core + ~250 air
Accommodation: 1,250 berths + 50 "austere" temporary berths as required.
Sensors + Combat Systems:
- Thales TACTICOS MS500 CMS (CEC-capable)
- Thales NS110 in a four-poster fixed-face setup, complete with SCOUT and staring EO sensor on each face
- Thales APAR block 1 in a four-corner setup for surface search and fire control
- Thales ICAS-derived phased array communications suite integrated into a Rohde & Schwarz communications suite
- Thales PFAS-derived sideways-looking LF flank-array with ATLAS MSO cylindrical MF chin array and Kongsberg MOAS
EW (ESM/ECM):
- OLQ-3 derived ECM/ESM suite fore and aft with Rohde & Schwarz R/C-ESM receiver group and distributed direction finding equipment
- 4x 62/80mm countermeasure launchers
- 2x centurion countermeasure launchers for 130/150mm countermeasures
- 2x4 Sea Spider hard-kill torpedo countermeasure dispensers
Armament:
- 48x (2x 24 blocks) Tactical-length Mk.41 cells for VL-ASROC, Sea Ceptor, S225X and SM-6MR
- 3x 76mm STRALES mounts, 3x 40mm mounts, 2x 23mm mounts, 4x 13.2mm Gatling RWS
- 2x2 tubes for 324mm torpedoes - Mk.50 and Mk.54
Aviation Facilities:
Aircraft Carried:
Nominal ASW Air-Group
6x Goshawk ASTOVL strike-fighters for top-cover and surface strike
12x Merlin for persistent ASW operations
3x Wildcats for plane-guard and general light duties
6x Hummingbirds for AEW and ASW/ASuW duties
6x Camcopters for surveillance duties
Landing Craft + Boats:
- 2x 7.5m RHIBs
- 4x CB18Ms or USVs up-to similar dimensions (Saab large USVs likely for ASW)
Class Members:
- IA.13 LCB Cerys
- IA.14 LCB Cáitriona (Banríon Cáitriona An Ríonmháthair)
- IA.15 LCB Fachtna
- IA.16 LCB Scáthach
- IA.17 LCB Princess Niamh (Banphrionsa Niamh)
- IA.18 LCB Queen Jane (Banríon Sinéad)

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AU Projects: | Banbha et al. | New England: The Divided States
Blood and Fire