Submarine Tenders
Alaunia, Artifex and Ausonia
These three ships have tended to the D1/9 class fleet subs and various R class subs since their construction in 1916. Alaunia originally tended to the D1/9 class subs and later the newer R-74 class subs. Ammunition, torpedo and fuel load out vary depending on the class of subs they tend to. The extra bunkerage for submarines is not usually used for full refueling as fuel capacity is not great so these tenders are usually accompanied by a small tanker. Also due to their size they are only used for maintenance and repair and not replenishment or crew accommodations, functions reserved for other purpose built ships. These ships have a hoist position on the bow used to lift subs partially out of water resulting in the use of a clipper bow and a sturdy bow sprit.
Alaunia , Atlantean Submarine tender laid down 1916
Displacement:
2,608 t light; 2,677 t standard; 3,351 t normal; 3,890 t full load
Dimensions: Length overall / water x beam x draught
407.12 ft / 365.00 ft x 46.00 ft x 12.70 ft (normal load)
124.09 m / 111.25 m x 14.02 m x 3.87 m
Armament:
2 - 3.00" / 76.2 mm guns in single mounts, 13.50lbs / 6.12kg shells, 1916 Model
Quick firing guns in deck mounts
on centreline ends, evenly spread
4 - 0.98" / 25.0 mm guns in single mounts, 0.48lbs / 0.22kg shells, 1916 Model
Breech loading guns in deck mounts
on side, all amidships
Weight of broadside 29 lbs / 13 kg
Shells per gun, main battery: 150
Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 2,300 shp / 1,716 Kw = 14.00 kts
Range 20,000nm at 10.00 kts
Bunker at max displacement = 1,212 tons
Complement:
219 - 286
Cost:
£0.174 million / $0.696 million
Distribution of weights at normal displacement:
Armament: 4 tons, 0.1 %
Machinery: 86 tons, 2.6 %
Hull, fittings & equipment: 1,018 tons, 30.4 %
Fuel, ammunition & stores: 743 tons, 22.2 %
Miscellaneous weights: 1,500 tons, 44.8 %
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
7,253 lbs / 3,290 Kg = 537.2 x 3.0 " / 76 mm shells or 1.9 torpedoes
Stability (Unstable if below 1.00): 1.12
Metacentric height 1.9 ft / 0.6 m
Roll period: 13.9 seconds
Steadiness - As gun platform (Average = 50 %): 54 %
- Recoil effect (Restricted arc if above 1.00): 0.01
Seaboat quality (Average = 1.00): 1.87
Hull form characteristics:
Hull has a flush deck
Block coefficient: 0.550
Length to Beam Ratio: 7.93 : 1
'Natural speed' for length: 19.10 kts
Power going to wave formation at top speed: 29 %
Trim (Max stability = 0, Max steadiness = 100): 29
Bow angle (Positive = bow angles forward): 30.00 degrees
Stern overhang: 30.00 ft / 9.14 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 21.00 ft / 6.40 m
- Forecastle (20 %): 14.00 ft / 4.27 m
- Mid (50 %): 14.00 ft / 4.27 m
- Quarterdeck (15 %): 14.00 ft / 4.27 m
- Stern: 14.00 ft / 4.27 m
- Average freeboard: 14.56 ft / 4.44 m
Ship tends to be wet forward
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 58.7 %
- Above water (accommodation/working, high = better): 142.7 %
Waterplane Area: 11,718 Square feet or 1,089 Square metres
Displacement factor (Displacement / loading): 197 %
Structure weight / hull surface area: 58 lbs/sq ft or 282 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.98
- Longitudinal: 1.44
- Overall: 1.02
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Excellent seaboat, comfortable, can fire her guns in the heaviest weather
Misc weights:
570 tons for fuel for subs (simmed as extra bunkerage)
500 tons for fuel
500 tons for ammunition and torpedo's
200 tons for Engineering workshop
200 tons for torpedo workshop
100 tons for two cranes