Następny
typ okrętów na bazie projektu uniwersalnego PU-450. Jest to mały, „bałtycki”
stawiacz min przeznaczony przede wszystkim do stawiania defensywnych zagród na
akwenach przybrzeżnych, w cieśninach, zatokach itp.
Jednostka
posiada adekwatne do stawianych przed nią zadań uzbrojenie, prędkość, zasięg i
wystarczające na Bałtyk właściwości morskie. Głównym uzbrojeniem okrętu są
miny, z których 32 przewożone są na odkrytym pokładzie rufowym, a dalszych 16
pod pokładem.
Sądzę, że
pomimo swojej prostoty i niewielkich rozmiarów są to udane jednostki z
perspektywami eksportowymi.
Nereida, Poland Minelayer laid down 1926
Displacement:
382
t light; 393 t standard; 450 t normal; 495 t full load
Dimensions: Length (overall / waterline) x
beam x draught (normal/deep)
(198,84
ft / 196,85 ft) x 24,61 ft x (7,38 / 7,89 ft)
(60,61
m / 60,00 m) x 7,50 m x (2,25 / 2,40 m)
Armament:
1
- 2,95" / 75,0 mm 55,0 cal gun - 13,01lbs / 5,90kg shells, 150 per gun
Dual purpose gun in deck mount, 1923 Model
1 x Single mount on centreline, forward deck
forward
1
- 1,57" / 40,0 mm 60,0 cal gun - 2,05lbs / 0,93kg shells, 600 per gun
Anti-air gun in deck mount, 1919 Model
1 x Single mount on centreline, aft deck aft 1
raised mount
2
- 0,51" / 13,0 mm 75,0 cal guns - 0,08lbs / 0,03kg shells, 2 400 per
gun
Machine guns in deck mounts, 1925 Model
2 x Single mounts on sides, forward deck centre
2 raised mounts
Weight of broadside 15 lbs / 7 kg
Mines
2
- 1 212,54 lbs / 550,00 kg mines + 48 reloads - 27,066 t total
in
Above water - Stern racks/rails
Machinery:
Diesel
Internal combustion motors,
Direct
drive, 2 shafts, 4 915 shp / 3 667 Kw = 23,00 kts
Range
3 300nm at 13,00 kts
Bunker
at max displacement = 102 tons
Complement:
48
- 63
Cost:
£0,126
million / $0,504 million
Distribution of weights at normal
displacement:
Armament:
38 tons, 8,5%
- Guns: 4 tons, 1,0%
- Weapons: 34 tons, 7,5%
Machinery:
157 tons, 35,0%
Hull,
fittings & equipment: 187 tons, 41,5%
Fuel,
ammunition & stores: 67 tons, 15,0%
Miscellaneous
weights: 0 tons, 0,0%
Overall survivability and seakeeping ability:
Survivability
(Non-critical penetrating hits needed to sink ship):
558 lbs / 253 Kg = 43,4 x 3,0 " / 75 mm
shells or 0,4 torpedoes
Stability
(Unstable if below 1.00): 1,27
Metacentric
height 0,9 ft / 0,3 m
Roll
period: 10,7 seconds
Steadiness - As gun platform (Average = 50 %): 71 %
-
Recoil effect (Restricted arc if above 1.00): 0,05
Seaboat
quality (Average = 1.00): 1,08
Hull form characteristics:
Hull
has rise forward of midbreak,
a normal bow and small transom stern
Block
coefficient (normal/deep): 0,440 / 0,453
Length
to Beam Ratio: 8,00 : 1
'Natural
speed' for length: 15,29 kts
Power
going to wave formation at top speed: 66 %
Trim
(Max stability = 0, Max steadiness = 100): 65
Bow
angle (Positive = bow angles forward): 7,50 degrees
Stern
overhang: 0,00 ft / 0,00 m
Freeboard
(% = length of deck as a percentage of waterline length):
Fore
end, Aft end
- Forecastle: 20,00%, 15,09 ft /
4,60 m, 14,11 ft / 4,30 m
- Forward deck: 30,00%, 14,11 ft / 4,30
m, 14,11 ft / 4,30 m
- Aft deck: 30,00%, 5,91 ft / 1,80 m, 5,91 ft / 1,80 m
- Quarter deck: 20,00%, 5,91 ft / 1,80
m, 5,91 ft / 1,80 m
- Average freeboard: 10,09 ft / 3,07 m
Ship
tends to be wet forward
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low =
better): 116,3%
-
Above water (accommodation/working, high = better): 124,5%
Waterplane
Area: 3 136 Square feet or 291 Square metres
Displacement
factor (Displacement / loading): 138%
Structure
weight / hull surface area: 34 lbs/sq ft or 164 Kg/sq metre
Hull
strength (Relative):
-
Cross-sectional: 0,86
-
Longitudinal: 3,61
-
Overall: 1,00
Cramped
machinery, storage, compartmentation space
Excellent
accommodation and workspace room
Ship
has slow, easy roll, a good, steady gun platform
Nereida (1926)
Okeanida (1926)
Najada (1926)
