Stawiacz min typu Nereida 1926 (3 szt.)

Stawiacz min typu Nereida 1926 (3 szt.)

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)