Shipbucket

HMSAS Pretoria

Due to the empire conference during the LNT South Africa like the other dominions had to build its agreed number of cruisers, she had put this off for budgetary reasons during the early 30s but by 35 she was pressured to do so as the deadline for replacing her two old C class ships was set on the signed paper as 1 JAN 1937.

The RSAN felt its only potential threat was AMC or long range raiders ether cruisers or PBs and that even a weak CL could inflict damage that would mission kill them. This only required 8x6" and a slow speed, the result was that the RSAN ordered the cheapest of the treaty cruisers.

Very cheap Light Cruiser, South Africa CL laid down 1935

Displacement:
3,016 t light; 3,228 t standard; 4,060 t normal; 4,725 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(453.88 ft / 450.00 ft) x 44.00 ft x (13.00 / 14.68 ft)
(138.34 m / 137.16 m) x 13.41 m x (3.96 / 4.48 m)

Armament:
8 - 6.00" / 152 mm 45.0 cal guns - 100.00lbs / 45.36kg shells, 250 per gun
Breech loading guns in deck mounts, 1913 Model (old surplus guns in new twin hand worked mounts to save costs)
4 x Twin mounts on centreline, evenly spread
2 raised mounts
4 - 4.00" / 102 mm 45.0 cal guns - 35.01lbs / 15.88kg shells, 200 per gun
Dual purpose guns in deck mounts, 1934 Model (standard RN HA guns)
2 x Twin mounts on sides, aft deck forward
6 - 0.79" / 20.0 mm 70.0 cal guns - 0.27lbs / 0.12kg shells, 4,000 per gun
Machine guns in deck mounts, 1934 Model (early Swiss contract as SA didn't want to pay for the RN standard quad 40mm due to low AA threat)
6 x Single mounts on sides, evenly spread
6 raised mounts
Weight of broadside 942 lbs / 427 kg
Main Torpedoes
8 - 21.0" / 533 mm, 21.00 ft / 6.40 m torpedoes - 1.422 t each, 11.376 t total
In 2 sets of deck mounted side rotating tubes
Main DC/AS Mortars
10 - 420.00 lbs / 190.51 kg Depth Charges + 50 reloads - 11.250 t total
in Stern depth charge racks

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 2.00" / 51 mm 300.00 ft / 91.44 m 10.00 ft / 3.05 m
Ends: Unarmoured
Main Belt covers 103 % of normal length

- Torpedo Bulkhead - Strengthened structural bulkheads: (this is simply backing for the 2" belt)
1.00" / 25 mm 350.00 ft / 106.68 m 27.00 ft / 8.23 m
Beam between torpedo bulkheads 44.00 ft / 13.41 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.00" / 25 mm - -
2nd: 0.30" / 8 mm - -
3rd: 1.00" / 25 mm - -

- Armoured deck - single deck:
For and Aft decks: 1.00" / 25 mm
Forecastle: 1.00" / 25 mm Quarter deck: 1.00" / 25 mm

- Conning towers: Forward 1.00" / 25 mm, Aft 1.00" / 25 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 24,036 shp / 17,931 Kw = 26.00 kts
Range 10,000nm at 16.00 kts
Bunker at max displacement = 1,497 tons

Complement:
253 - 330

Cost:
£1.267 million / $5.069 million

Distribution of weights at normal displacement:
Armament: 168 tons, 4.1 %
- Guns: 131 tons, 3.2 %
- Weapons: 37 tons, 0.9 %
Armour: 882 tons, 21.7 %
- Belts: 245 tons, 6.0 %
- Torpedo bulkhead: 350 tons, 8.6 %
- Armament: 18 tons, 0.5 %
- Armour Deck: 258 tons, 6.4 %
- Conning Towers: 11 tons, 0.3 %
Machinery: 683 tons, 16.8 %
Hull, fittings & equipment: 1,083 tons, 26.7 %
Fuel, ammunition & stores: 1,043 tons, 25.7 %
Miscellaneous weights: 200 tons, 4.9 %
- Hull below water: 10 tons (ADSIC)
- On freeboard deck: 150 tons (three seaplanes, crane and catapult)
- Above deck: 40 tons (director and spotting tops)

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
8,393 lbs / 3,807 Kg = 77.7 x 6.0 " / 152 mm shells or 1.8 torpedoes
Stability (Unstable if below 1.00): 1.36
Metacentric height 2.5 ft / 0.8 m
Roll period: 11.7 seconds
Steadiness - As gun platform (Average = 50 %): 75 %
- Recoil effect (Restricted arc if above 1.00): 0.35
Seaboat quality (Average = 1.00): 1.50

Hull form characteristics:
Hull has a flush deck,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0.552 / 0.569
Length to Beam Ratio: 10.23 : 1
'Natural speed' for length: 21.21 kts
Power going to wave formation at top speed: 52 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 10.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 25.00 %, 22.00 ft / 6.71 m, 17.00 ft / 5.18 m
- Forward deck: 30.00 %, 17.00 ft / 5.18 m, 14.00 ft / 4.27 m
- Aft deck: 20.00 %, 14.00 ft / 4.27 m, 14.00 ft / 4.27 m
- Quarter deck: 25.00 %, 14.00 ft / 4.27 m, 14.00 ft / 4.27 m
- Average freeboard: 15.70 ft / 4.79 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 69.0 %
- Above water (accommodation/working, high = better): 149.8 %
Waterplane Area: 13,844 Square feet or 1,286 Square metres
Displacement factor (Displacement / loading): 140 %
Structure weight / hull surface area: 68 lbs/sq ft or 331 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.97
- Longitudinal: 1.36
- Overall: 1.00
Excellent machinery, storage, compartmentation space
Excellent accommodation and workspace room
Ship has slow, easy roll, a good, steady gun platform
Good seaboat, rides out heavy weather easily

Due to delays in production she was commissioned slightly different in 1938


PS- I thought I should post it even if its to late for the completion and I hope Charguizard and Hood don't mind if I borrowed parts and the paint scheme from them, don't think its sufficient for needing credits?

I don't see anything here that requires my name on it.

She's ugly but very charming nonetheless!

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w o r k l i s t :
Hatsuyuki-class Escort Ships . . . <3

Oh I've never seen a WW2(ish) era South African ship before!

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I was simply thinking about going cheaper than a Arethusa class for the treaty completion to be different and then had to think who would be unwilling to buy more....

Just annoyed that I was 5 days late and it still don't look great with that big grey hangar.

Maybe lenghtening the forecastle sheer back to the hangar area could mitigate a little the apparent bulkyness of the structure.

A quick touch I made, just a suggestion anyway. You obviously don't have to, it's your ship after all

That's an interest take anyway, a nice pocket cruiser.

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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

A very interesting design and one that is different from the classical RN style of light cruiser.

I only have a couple of points.
Maybe a touch more freeboard forward would help lessen the impact of the hangar?
Are you sure there is room aft for two torpedo tubes and the superstructure on 44ft beam? Even the 50ft 6in Didos only had a much smaller deckhouse between their quad tubes. Its a problem I noticed on the cruiser challenge, too many folks forget how much deck space they take up, especially to train outboard.

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Hood's Worklist
English Electric Canberra FD
Interwar RN Capital Ships
Super-Darings
Never-Were British Aircraft

Thanks for the feedback,

Hood Yes and Yes, after BB1987 suggested it I have started a version with the fore deck much flatter to a brake. The TT will move under the 4" with the boats just on a platform between the funnel and aft structure.

With changes suggested.

I'm not sure if a cross deck catapult would work on your breadth of hull. Just measuring the UK cats off the Leander class (same timeline) are just over 50 feet on their turntables. The first crossdecks on UK ships are the Southamptons which were over 60 feet. The other problem of course is that your aircraft, even with folding wings would not fit in your hangar with the funnel in the center.

1938 you could possibly swap out the 6" for 5.25" or the 4.5" used on Scylla (same as used on Ark Royal), widen the hull (60ft+), increase power to 40k (same as C/D's) 26-27 knots on a slightly bigger hull, lose the secondaries for the dual purpose mains, give your ship a better AA fit.

Your choice of course, just my two cents. I have done a few of these 'Light Patrol Cruisers', everything from new builds to converting the older Town Class (1914-15) types. The biggest problem I run across is hull breadth to be able to put aircraft handling facilities on board.

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