WesWorld

As the CT does not allow cruiser guns bigger than 6" the 170 mm on the Hasta Luegos is obviously too big. The Armada first thought about replacing them with twin 6" turrets but considered that a waste of space and ended up deciding on a triple 130 mm mount on the rationale that the SCs were there to operate with te destroyers anyway.

Hasta Luego, Iberia Scout Cruiser laid down 1919

Displacement:
4,241 t light; 4,369 t standard; 4,567 t normal; 4,707 t full load
Loading submergence 391 tons/feet

Dimensions:
508.53 ft x 45.28 ft x 15.09 ft (normal load)
155.00 m x 13.80 m x 4.60 m

Armament:
6 - 5.12" / 130 mm guns (2 Main turrets x 3 guns)
6 - 2.24" / 57 mm AA guns
4 - 0.53" / 14 mm guns
Weight of broadside 436 lbs / 198 kg
8 - 23.6" / 600 mm above water torpedoes

Armour:
Belt 1.97" / 50 mm, ends unarmoured
Belts cover 147 % of normal area
Main turrets 1.97" / 50 mm, AA gun shields 0.79" / 20 mm
Armour deck 1.18" / 30 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 3 shafts, 53,509 shp / 39,918 Kw = 32.00 kts
Range 5,000nm at 10.00 kts

Complement:
277 - 361

Cost:
£1.001 million / $4.002 million

Distribution of weights at normal displacement:
Armament: 55 tons, 1.2 %
Armour: 685 tons, 15.0 %
Belts: 313 tons, 6.9 %, Armament: 73 tons, 1.6 %, Armour Deck: 299 tons, 6.5 %
Conning Tower: 0 tons, 0.0 %, Torpedo bulkhead: 0 tons, 0.0 %
Machinery: 1,888 tons, 41.3 %
Hull, fittings & equipment: 1,614 tons, 35.3 %
Fuel, ammunition & stores: 326 tons, 7.1 %
Miscellaneous weights: 0 tons, 0.0 %

Metacentric height 2.3

Remarks:
Caution: Hull subject to strain in open-sea
Hull space for machinery, storage & compartmentation is cramped
Room for accommodation & workspaces is adequate
Ship has slow, easy roll, a good, steady gun platform

Estimated overall survivability and seakeeping ability:
Relative margin of stability: 1.25
Shellfire needed to sink: 2,591 lbs / 1,175 Kg = 38.7 x 5.1 " / 130 mm shells
(Approx weight of penetrating shell hits needed to sink ship excluding critical hits)
Torpedoes needed to sink: 0.6
(Approx number of typical torpedo hits needed to sink ship)
Relative steadiness as gun platform: 71 %
(Average = 50 %)
Relative rocking effect from firing to beam: 0.28
Relative quality as seaboat: 1.17

Hull form characteristics:
Block coefficient: 0.460
Sharpness coefficient: 0.31
Hull speed coefficient 'M': 9.37
'Natural speed' for length: 22.55 kts
Power going to wave formation at top speed: 56 %
Trim: 61
(Maximise stabilty/flotation = 0, Maximise steadiness/seakeeping = 100)

Estimated hull characteristics & strength:
Underwater volume absorbed by magazines and engineering spaces: 143.0 %
Relative accommodation and working space: 107.6 %
(Average = 100%)
Displacement factor: 93 %
(Displacement relative to loading factors)
Relative cross-sectional hull strength: 0.84
(Structure weight / hull surface area: 67 lbs / square foot or 327 Kg / square metre)
Relative longitudinal hull strength: 1.07
(for 16.40 ft / 5.00 m average freeboard, freeboard adjustment 3.46 ft)
Relative composite hull strength: 0.86

The ships will be comissioned this way.

here is the gun:


130 mm/60 cruiser gun


Caliber = 13.0 cm (5.1 inch)
Shell weight = 40 kg (88 lbs)
Muzzle velocity = 862 m/s (2827 fps)

Relative ballistic performance: 1.00

Muzzle energy = 14.853 megajoules = 5473.2 foot-tons

Relative muzzle energy: 1.28

Barrel length: 60 calibers


Elevation Range Time Velocity Fall Angle

2.5 deg 5200 meters 7.2 sec 613 m/s 3.1 deg
5.0 deg 8700 meters 13.7 sec 490 m/s 7.3 deg
7.5 deg 11300 meters 19.6 sec 420 m/s 12.1 deg
10.0 deg 13400 meters 25.1 sec 377 m/s 17.1 deg
12.5 deg 15200 meters 30.2 sec 350 m/s 22.2 deg
15.0 deg 16700 meters 35.2 sec 333 m/s 27.3 deg
20.0 deg 19200 meters 44.5 sec 317 m/s 36.7 deg
25.0 deg 21200 meters 53.2 sec 316 m/s 44.5 deg
30.0 deg 22700 meters 61.4 sec 323 m/s 50.9 deg
35.0 deg 23900 meters 69.3 sec 333 m/s 56.2 deg
40.0 deg 24600 meters 76.8 sec 344 m/s 60.5 deg
45.0 deg 24800 meters 83.9 sec 356 m/s 64.2 deg
50.0 deg 24600 meters 90.5 sec 367 m/s 67.3 deg


Armor Penetration - Vertical Belt Armor

(Relative armor quality, 1.00)

Maximum penetration: 31.17 cm


Elevation Range Belt Deck

1.0 deg 2500 meters 25 cm
2.4 deg 5000 meters 20 cm
4.7 deg 8300 meters 15 cm
8.0 deg 11800 meters ... 2 cm
9.6 deg 13100 meters 10 cm
19.4 deg 18900 meters ... 4 cm
26.6 deg 21700 meters 5 cm
30.0 deg 22700 meters ... 6 cm
42.7 deg 24800 meters ... 8 cm


Maximum range = 24800 meters at 45.0 deg elevation


cheers

Bernhard

Re-arming them this way would mean to change nearly everything. The 17cm guns were single shields right? But now you´re using 13cm tripple turrets. Therefor you´ll need barbets and a completely different magazin layout. I doubt this can be easily done. I would mean to totally re-design the whole ship. All interna have to be changed as well as the superstructure.

I´m not sure if this is very clever.

If you´re using a tripple shield instead, you might end up not needing barbets (but still different mags) but with the same problems the british faced with their tripple shields on the R-class BCs.

In addition, I think 5000nm at 10kn is too short legged, even if those ships are meant to operate with DDs who will also have a short range. When operating with DDs this cruiser will be travelling at more than 20kn most of the time, I guess, and I´m pretty sure its range will drop to a mere ~2800nm in this case. Hardly enough to patrol more than your coastline, though.

I also looked at the guns stats and I think with such a very high muzzle energy (which exceeds average values by far) you´ll have a very, very short barrel life and, most likely, muzzle blast interference, especially when using a tripple mount on such a narrow hull where you can´t use a mount with enough space between the mounts.

So the high muzzle energy grants you good striking power, maybe comparable to a heavier gun against a belt, but you will not hit anything with such a gun - most likely - due to tear and wear of the barrel and shell dispersion.

(Btw, I also doubt that such a gun could or would be build in 1919. Medium caliber guns with a caliber length of 60 didn´t come up until the 30s historically, IIRC, but you may proof me wrong. Do you have stats for a comparable gun at hand?)

Well, if you look up the Hasta La Vistas you will see that they had 17cm twin turrets and we discussed this in ICQ once. And on the gun, now I remember why I had a /50 sitting right next to it:


130 mm/50 scout cruiser gun


Caliber = 13.0 cm (5.1 inch)
Shell weight = 40 kg (88 lbs)
Muzzle velocity = 763 m/s (2503 fps)

Relative ballistic performance: 1.00

Muzzle energy = 11.648 megajoules = 4292.3 foot-tons

Relative muzzle energy: 1.00

Barrel length: 50 calibers


Elevation Range Time Velocity Fall Angle

2.5 deg 4300 meters 6.5 sec 576 m/s 3.0 deg
5.0 deg 7300 meters 12.4 sec 474 m/s 6.9 deg
7.5 deg 9700 meters 17.8 sec 412 m/s 11.2 deg
10.0 deg 11600 meters 23.0 sec 371 m/s 16.1 deg
12.5 deg 13200 meters 27.8 sec 345 m/s 20.9 deg
15.0 deg 14600 meters 32.4 sec 328 m/s 25.7 deg
20.0 deg 16900 meters 41.1 sec 310 m/s 34.7 deg
25.0 deg 18700 meters 49.3 sec 307 m/s 42.7 deg
30.0 deg 20000 meters 57.0 sec 312 m/s 49.3 deg
35.0 deg 21000 meters 64.3 sec 320 m/s 54.8 deg
40.0 deg 21600 meters 71.2 sec 330 m/s 59.3 deg
45.0 deg 21700 meters 77.7 sec 341 m/s 63.1 deg
50.0 deg 21400 meters 83.8 sec 351 m/s 66.5 deg


Armor Penetration - Vertical Belt Armor

(Relative armor quality, 1.00)

Maximum penetration: 26.51 cm


Elevation Range Belt Deck

1.8 deg 3200 meters 20 cm
4.2 deg 6500 meters 15 cm
9.1 deg 10900 meters ... 2 cm
9.4 deg 11200 meters 10 cm
21.2 deg 17400 meters ... 4 cm
26.6 deg 19100 meters 5 cm
32.8 deg 20600 meters ... 6 cm
46.9 deg 21600 meters ... 8 cm


Maximum range = 21700 meters at 44.2 deg elevation


don't have te time to dig around for preceents right now, sorry.

cheers

Bernhard

Those 88lb shells to be fired seem a little heavy when you are using a 5.1" gun. The UK 5.25 fired 80lb shells and the US 5" gun fired 56lb shells.
80lb shells were found to be a little too heavy for hand loading with 5.25" gun. I think a 60-70lb shell would be better and give your 60caliber rifle a very long range.

Usually older ships with sheilded mounts tended to rearm with lighter guns that were also sheilded. I think a design that went from sheilded mounts to barbet mounts. The only one i can think of was the H.M.S. Enterprize when she landed a single 6" gun for an experimental twin mounting that was later used in the Arethusa and leander designs. My 5.5" cruisers will later mount a lighter 4.5" DP shielded mount as its IMO pointless to drastically alter older ships with the exception of BB/BC's.