WesWorld

Subchasers

SC-13-class Coastal Subchasers - Atlantean Type-4C subchasers
- SC-13 (SC-13) - 1932
- SC-14 (SC-14) - 1932
- SC-15 (SC-15) - 1932
- SC-16 (SC-16) - 1932
- SC-17 (SC-17) - 1932
- SC-18 (SC-18) - 1932
- SC-19 (SC-19) - 1932
- SC-20 (SC-20) - 1932
- SC-21 (SC-21) - 1932
- SC-22 (SC-22) - 1932
- SC-23 (SC-23) - 1932
- SC-24 (SC-24) - 1932

Loa-class Subchaser - 1944
- Loa: Laid down at Valdivia January 1944, completed May 1944.
- Maule: Laid down at Valdivia April 1944, completed August 1944.
- Lauca: Laid down at Valdivia July 1944, completed November 1944.
- Maipo: Laid down at Valdivia October 1944, completed February 1945.
- Rapel: Laid down at Valdivia January 1945, completed May 1945.
- Itata: Laid down at Valdivia April 1944, completed August 1945.
- Pascua: Laid down at Valdivia July 1945, completed November 1945.
- Tinguiririca: Laid down at Valdivia October 1945, completed February 1946.
- Azopardo: Laid down at Valdivia January 1946, completed May 1946.
- Cisnes: Laid down at Valdivia April 1946, completed August 1946.
- Petrohué: Laid down at Valdivia July 1946, completed November 1946.
- Colún: Laid down at Valdivia October 1946, completed February 1947.

Motor Torpedo Boats/High Speed Gunboats

Vina del Mar-class Sea Gun Boat - 1940
- Vina del Mar (SGB-X-01) - 1940

Aldebarán-class Sea Gun Boat - 1942
- Aldebarán (SGB-01) - 1942
- Denébola (SGB-02) - 1942
- Capella (SGB-03) - 1942
- Sirio (SGB-04) - 1942
- Matar (SGB-05) - 1942
- Thuban (SGB-06) - 1942
- Regulus (SGB-07) - 1942
- Fomalhaut (SGB-08) - 1942
- Hassaleh (SGB-09) - 1942
- Shaula (SGB-10) - 1942
- Sadalmelik (SGB-11) - 1942
- Altarf (SGB-12) - 1942
- Unukalhai (SGB-13) - 1943
- Mekbuda (SGB-14) - 1943
- Edasich (SGB-15) - 1943
- Aludra (SGB-16) - 1943
- Adhara (SGB-17) - 1943
- Algol (SGB-18) - 1943
- Errai (SGB-19) - 1943
- Rigilkent (SGB-20) - 1943
- Antares (SGB-21) - 1943
- Pléyone (SGB-22) - 1943
- Rasalhague (SGB-23) - 1943
- Mizar (SGB-24) - 1943

SC-13-class, Chilean (Atlantean) Subchaser laid down 1932

Displacement:
105 t light; 110 t standard; 121 t normal; 129 t full load

Dimensions: Length overall / water x beam x draught
114.33 ft / 110.00 ft x 18.00 ft x 5.20 ft (normal load)
34.85 m / 33.53 m x 5.49 m x 1.58 m

Armament:
1 - 3.00" / 76.2 mm guns in single mounts, 13.50lbs / 6.12kg shells, 1932 Model
Breech loading gun in deck mount
on centreline forward
4 - 1.46" / 37.1 mm guns (3 mounts), 1.56lbs / 0.71kg shells, 1932 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
4 - 0.50" / 12.7 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1932 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
Weight of broadside 20 lbs / 9 kg
Shells per gun, main battery: 200

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.00" / 25 mm - -

Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 1,149 shp / 857 Kw = 18.00 kts
Range 1,600nm at 12.00 kts
Bunker at max displacement = 18 tons

Complement:
17 - 23

Cost:
£0.048 million / $0.191 million

Distribution of weights at normal displacement:
Armament: 2 tons, 2.1 %
Armour: 2 tons, 1.3 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 2 tons, 1.3 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 34 tons, 28.1 %
Hull, fittings & equipment: 57 tons, 47.5 %
Fuel, ammunition & stores: 15 tons, 12.7 %
Miscellaneous weights: 10 tons, 8.3 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
150 lbs / 68 Kg = 11.1 x 3.0 " / 76 mm shells or 0.2 torpedoes
Stability (Unstable if below 1.00): 1.16
Metacentric height 0.5 ft / 0.2 m
Roll period: 10.7 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.14
Seaboat quality (Average = 1.00): 1.05

Hull form characteristics:
Hull has a flush deck
Block coefficient: 0.410
Length to Beam Ratio: 6.11 : 1
'Natural speed' for length: 10.49 kts
Power going to wave formation at top speed: 70 %
Trim (Max stability = 0, Max steadiness = 100): 48
Bow angle (Positive = bow angles forward): 20.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 11.90 ft / 3.63 m
- Forecastle (20 %): 7.51 ft / 2.29 m
- Mid (50 %): 7.51 ft / 2.29 m
- Quarterdeck (15 %): 7.51 ft / 2.29 m
- Stern: 7.51 ft / 2.29 m
- Average freeboard: 7.86 ft / 2.40 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 117.2 %
- Above water (accommodation/working, high = better): 103.2 %
Waterplane Area: 1,226 Square feet or 114 Square metres
Displacement factor (Displacement / loading): 121 %
Structure weight / hull surface area: 24 lbs/sq ft or 119 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.81
- Longitudinal: 7.78
- Overall: 1.02
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is adequate

Ships in Class:
- SC-13 (SC-13) - 1932
- SC-14 (SC-14) - 1932
- SC-15 (SC-15) - 1932
- SC-16 (SC-16) - 1932
- SC-17 (SC-17) - 1932
- SC-18 (SC-18) - 1932
- SC-19 (SC-19) - 1932
- SC-20 (SC-20) - 1932
- SC-21 (SC-21) - 1932
- SC-22 (SC-22) - 1932
- SC-23 (SC-23) - 1932
- SC-24 (SC-24) - 1923

Vina del Mar-class Sea Gunboat Experimental (Type 1)
Designer and Builder: William Denny and Brothers
Length (o/a): 147.6 feet (45 meters)
Beam: 22 feet (6.7 meters)
Draft: 8 feet (2.44 meters)
Displacement: 180 tons light, 220 tons standard, 260 tons loaded
Propulsion: twin Metrovick geared steam turbines, 1 boiler delivering 5965 kW (8,000 shp) to two shafts
Range: 1000nm @ 12 knots
Speed: 35 knots maximum; 26 knots in Sea State 4
Crew: 32 men
Armament:
- 1 x 57mm/L50 gun
- 4 x 1.1"/L70 AA guns in twin mountings
- 6 x 21" torpedoes
- 6 x DCs or mines
Ships in Class: Vina del Mar
Notes and History: In 1940, facing the expected obsolescence of nearly thirty-six destroyers in only five years, the Armada de Chile investigated whether a smaller vessel, derived from an oversize MTB, could serve as a coastal patrol vessel in lieu of a full-sized destroyer. A single experimental vessel was ordered from William Denny and Brothers in the UK to investigate the concept's utility. After an initial working-up period off western Scotland, the Vina del Mar arrived in Chile and was heavily tested by the Armada, leading to the eventual order for the Star-class Sea Gunboats in 1942.

Star-class Sea Gunboat
Designer: Denny & Sons
Length (o/a): 147 feet 8 in (45 meters)
Length (w/l): 140 feet (42.7 meters)
Beam: 22 feet (6.7 meters)
Draft: 8 feet (2.44 meters)
Displacement: 180 tons light, 220 tons standard, 260 tons loaded
Propulsion: Two Austral marine diesels (1,600hp each) plus Metrovick geared steam turbine, 1 boiler delivering 5965 kW (8,000 shp) to two shafts
Range: 1000nm @ 20 knots
Speed: 37 knots maximum; 27 knots in Sea State 4
Crew: 31 men
Armament:
- 1 x 3" gun in DP mounting
- 4 x 1.1"/L70 AA guns in twin mountings
- 2 x 21" torpedoes
- 6 x DCs or mines
- Kodkod launch rails
Electronics: Type 103 "Nalca" dradis, SPR-42 sonar
Ships in Class: Aldebarán, Denébola, Capella, Sirio, Matar, Thuban, Regulus, Fomalhaut, Hassaleh, Shaula, Sadalmelik, Altarf, Unukalhai, Mekbuda, Edasich, Aludra, Adhara, Algol, Errai, Rigilkent, Antares, Pléyone, Rasalhague, Mizar
Ships Planned: N/A
Notes: 24x boats, 6x ordered from Great Britain. 18x built locally by ASMAR and ASENAV.

Loa-class, Chilean Patrullero laid down 1944
This subchaser design originated in the United States and was purchased by the Chilean Navy for construction in the ASENAV shipyards of Valdivia. They will replace, in part or in whole, the aging SC-1 subchaser class acquired from Atlantis. The class shares many similarities with the smaller YDM-1 class minesweepers, but the Loa-class incorporates more speed and a higher level of seakeeping. The ships will be named after Chilean rivers.

Displacement:
250 t light; 265 t standard; 313 t normal; 352 t full load

Dimensions: Length overall / water x beam x draught
178.14 ft / 175.00 ft x 23.00 ft x 6.90 ft (normal load)
54.30 m / 53.34 m x 7.01 m x 2.10 m

Armament:
1 - 3.00" / 76.2 mm guns in single mounts, 13.50lbs / 6.12kg shells, 1944 Model
Dual purpose gun in deck mount
on centreline aft
2 - 1.57" / 40.0 mm guns (1x2 guns), 1.95lbs / 0.88kg shells, 1944 Model
Anti-aircraft guns in deck mount
on centreline forward
4 - 1.10" / 27.9 mm guns in single mounts, 0.67lbs / 0.30kg shells, 1944 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
Weight of broadside 20 lbs / 9 kg
Shells per gun, main battery: 650

Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 1,996 shp / 1,489 Kw = 20.00 kts
Range 3,500nm at 15.00 kts
Bunker at max displacement = 87 tons

Complement:
36 - 48

Cost:
£0.121 million / $0.484 million

Distribution of weights at normal displacement:
Armament: 3 tons, 0.8 %
Machinery: 51 tons, 16.3 %
Hull, fittings & equipment: 146 tons, 46.7 %
Fuel, ammunition & stores: 63 tons, 20.3 %
Miscellaneous weights: 50 tons, 16.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
667 lbs / 303 Kg = 49.4 x 3.0 " / 76 mm shells or 0.6 torpedoes
Stability (Unstable if below 1.00): 1.10
Metacentric height 0.7 ft / 0.2 m
Roll period: 11.9 seconds
Steadiness - As gun platform (Average = 50 %): 71 %
- Recoil effect (Restricted arc if above 1.00): 0.08
Seaboat quality (Average = 1.00): 1.74

Hull form characteristics:
Hull has a flush deck
and transom stern
Block coefficient: 0.394
Length to Beam Ratio: 7.61 : 1
'Natural speed' for length: 15.70 kts
Power going to wave formation at top speed: 61 %
Trim (Max stability = 0, Max steadiness = 100): 41
Bow angle (Positive = bow angles forward): 10.00 degrees
Stern overhang: 0.50 ft / 0.15 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 15.00 ft / 4.57 m
- Forecastle (25 %): 12.00 ft / 3.66 m
- Mid (50 %): 9.00 ft / 2.74 m
- Quarterdeck (15 %): 9.00 ft / 2.74 m
- Stern: 10.00 ft / 3.05 m
- Average freeboard: 10.50 ft / 3.20 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 79.6 %
- Above water (accommodation/working, high = better): 130.5 %
Waterplane Area: 2,563 Square feet or 238 Square metres
Displacement factor (Displacement / loading): 182 %
Structure weight / hull surface area: 29 lbs/sq ft or 142 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.82
- Longitudinal: 5.84
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Breakdown of Miscellaneous Weights:
- 10 tons for Suite-42b electronics
- 8 tons for Kodkod antisubmarine rocket-launched depth charges
- 6 tons for depth charges (28x420-lb bombs)
- 16 tons for paravanes and other minesweeping equipment
- 10 tons other miscellaneous
50 tons total miscellaneous weight

Suite-42b Electronics:
- Type 103 "Nalca" navigational surface and air search radar (1 radar, 2 tons)
- SPR-42 Sound Projector-Receivers (5 tons)
- Roth-389b backup diesel generator set (3 tons)

Ships in Class:
- Loa: Laid down at Valdivia January 1944, completed May 1944.
- Maule: Laid down at Valdivia April 1944, completed August 1944.
- Lauca: Laid down at Valdivia July 1944, completed November 1944.
- Maipo: Laid down at Valdivia October 1944, completed February 1945.
- Rapel: Laid down at Valdivia January 1945, completed May 1945.
- Itata: Laid down at Valdivia April 1944, completed August 1945.
- Pascua: Laid down at Valdivia July 1945, completed November 1945.
- Tinguiririca: Laid down at Valdivia October 1945, completed February 1946.
- Azopardo: Laid down at Valdivia January 1946, completed May 1946.
- Cisnes: Laid down at Valdivia April 1946, completed August 1946.
- Petrohué: Laid down at Valdivia July 1946, completed November 1946.
- Colún: Laid down at Valdivia October 1946, completed February 1947.