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This design was one brought forward to meet the needs of the Empresa Nacional de Navegaceon for new tonnage, with the intent of constructing at least six vessels over the next several years.

Atahualpa, Peruvian Cargo Ship laid down 1947

Displacement: 7,218 t light; 7,434 t standard; 10,757 t normal; 13,415 t full load

Dimensions: Length overall / water x beam x draught

392.55 ft / 386.15 ft x 55.77 ft x 24.28 ft (normal load) [119.65 m / 117.70 m x 17.00 m x 7.40 m]

Machinery:

Diesel Internal combustion motors, Geared drive, 1 shaft, 5,275 shp / 3,935 Kw = 14.50 kts
Range 50,000nm at 12.00 kts (actual 12,500 nm, see notes)
Bunker at max displacement = 5,981 tons

Complement: 53-89 (reduced for commercial service)

Cost: £1.970 million / $7.880 million

Distribution of weights at normal displacement:

Armament: 0 tons, 0.0 %
Machinery: 130 tons, 1.2 %
Hull, fittings & equipment: 5,888 tons, 54.7 %
Fuel, ammunition & stores: 3,538 tons, 32.9 %
Miscellaneous weights: 1,200 tons, 11.2 %

Overall survivability and seakeeping ability:

Survivability (Non-critical penetrating hits needed to sink ship): 5,058 lbs / 2,294 Kg = 46.84 x 6" /152 mm shells or 1.1 torpedoes (reduced for commercial service)
Stability (Unstable if below 1.00): 1.20
Metacentric height 2.9 ft / 0.9 m
Roll period: 13.7 seconds
Steadiness - As gun platform (Average = 50 %): 79 %
- Recoil effect (Restricted arc if above 1.00): 0.00
Seaboat quality (Average = 1.00): 1.55

Hull form characteristics:

Hull has raised forecastle, raised quarterdeck
Block coefficient: 0.720
Length to Beam Ratio: 6.92: 1
'Natural speed' for length: 19.65 kts
Power going to wave formation at top speed: 37 %
Trim (Max stability = 0, Max steadiness = 100): 51
Bow angle (Positive = bow angles forward): 18.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 19.69 ft / 6.00 m
- Forecastle (20 %): 17.06 ft / 5.20 m (11.48 ft / 3.50 m aft of break)
- Mid (50 %): 11.48 ft / 3.50 m
- Quarterdeck (10 %): 17.06 ft / 5.20 m (11.48 ft / 3.50 m before break)
- Stern: 17.06 ft / 5.20 m
- Average freeboard: 13.37 ft / 4.07 m
Ship tends to be wet forward

Ship space, strength and comments:

Space - Hull below water (magazines/engines, low = better): 17.9 %
- Above water (accommodation/working, high = better): 72.6 %
Waterplane Area: 17,503 Square feet or 1,626 Square meters
Displacement factor (Displacement / loading): 736 %
Structure weight / hull surface area: 223 lbs/sq ft or 1,086 Kg/sq meter
Hull strength (Relative):
- Cross-sectional: 2.98
- Longitudinal: 4.42
- Overall: 3.10
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is cramped
Ship has slow, easy roll, a good, steady gun platform
Excellent seaboat, comfortable, rides out heavy weather easily

Low-stowed cargo simmed as additional bunkers. Actual radius 12,500 nm on bunkers of 871 tons. Remaining bunkers represent cargo ~ 1,450 tons

Breakdown of miscellaneous weight:

Provision for working deck gear - 50 tons per hatch for four hatches - 200 tons
Provision for up to six cabin passengers, with amenities - 200 tons
High stowed and deck cargo - 800 tons

Nominal characteristics: 3,755 grt, 2,145 nrt, 6,885 dwt.

This design was one brought forward to meet the needs of the Empresa Nacional de Navegaceon for new tonnage. It is designed specifically for the carriage of bulk cargos of grain or minerals.

Rio Santa, Peruvian Ore Carrier laid down 1947

Displacement: 5,367 t light; 5,588 t standard; 11,031 t normal; 15,385 t full load

Dimensions: Length overall / water x beam x draught

446.32 ft / 438.65 ft x 55.77 ft x 24.28 ft (normal load) [136.04 m / 133.70 m x 17.00 m x 7.40 m]

Machinery:

Diesel Internal combustion motors, Geared drive, 1 shaft, 4,583 shp / 3,419 Kw = 14.00 kts
Range 100,000nm at 11.00 kts ((actual 15,000 nm, see notes)
Bunker at max displacement = 9,797 tons

Complement: 53-70 (reduced for commercial service)

Cost: £1.482 million / $5.926 million

Distribution of weights at normal displacement:

Armament: 0 tons, 0.0 %
Machinery: 113 tons, 1.0 %
Hull, fittings & equipment: 4,954 tons, 44.9 %
Fuel, ammunition & stores: 5,664 tons, 51.3 %
Miscellaneous weights: 300 tons, 2.7 %

Overall survivability and seakeeping ability:

Survivability (Non-critical penetrating hits needed to sink ship): 14,593 lbs / 6,619 Kg = 135.1 x 6 "/ 152 mm shells or 3.2 torpedoes (reduced for commercial service)
Stability (Unstable if below 1.00): 1.39
Metacentric height 3.7 ft / 1.1 m
Roll period: 12.2 seconds
Steadiness - As gun platform (Average = 50 %): 100 %
- Recoil effect (Restricted arc if above 1.00): 0.00
Seaboat quality (Average = 1.00): 2.00

Hull form characteristics:

Hull has raised forecastle
Block coefficient: 0.650
Length to Beam Ratio: 7.86: 1
'Natural speed' for length: 20.94 kts
Power going to wave formation at top speed: 29 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 18.00 degrees
Stern overhang: -1.64 ft / -0.50 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 23.62 ft / 7.20 m
- Forecastle (10 %): 22.97 ft / 7.00 m (18.04 ft / 5.50 m aft of break)
- Mid (30 %): 18.04 ft / 5.50 m
- Quarterdeck (30 %): 18.04 ft / 5.50 m
- Stern: 18.04 ft / 5.50 m
- Average freeboard: 18.56 ft / 5.66 m

Ship space, strength and comments:

Space - Hull below water (magazines/engines, low = better): 8.3 %
- Above water (accommodation/working, high = better): 118.3 %
Waterplane Area: 18,479 Square feet or 1,717 Square meters
Displacement factor (Displacement / loading): 1,000 %
Structure weight / hull surface area: 161 lbs/sq ft or 788 Kg/sq meter
Hull strength (Relative):
- Cross-sectional: 1.98
- Longitudinal: 3.64
- Overall: 2.11
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is adequate
Ship has slow, easy roll, a good, steady gun platform
Excellent seaboat, comfortable, rides out heavy weather easily

True bunkers 863 tons for a radius of 15,000 nm. Additional bunkers simmed as low-stowed cargo, 4,580 tons.

Residual composite strength represents strengthened deck coamings and structure for carriage of heavy cargos.

Breakdown of miscellaneous weight:

Cargo handling gear - 300 tons

Nominal characteristics: 5,238 grt, 2,536 nrt, 7,184 dwt