N-class

[damocles]

N class, Holland  auxiliary laid down 1916

Displacement:
   3,536 t light; 3,620 t standard; 4,214 t normal; 4,688 t full load

Dimensions: Length overall / water x beam x draught
   393.70 ft / 393.70 ft x 49.21 ft x 13.12 ft (normal load)
   120.00 m / 120.00 m x 15.00 m  x 4.00 m

Armour:

  - Conning tower: 0.98" / 25 mm

Machinery:
   Diesel Internal combustion generators,
   Electric motors, 4 shafts, 23,313 shp / 17,392 Kw = 25.00 kts
   Range 10,000nm at 12.00 kts
   Bunker at max displacement = 1,068 tons

Complement:
   260 - 339

Cost:
   £0.402 million / $1.606 million

Distribution of weights at normal displacement:
   Armament: 0 tons, 0.0 %
   Armour: 6 tons, 0.1 %
      - Belts: 0 tons, 0.0 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 0 tons, 0.0 %
      - Armour Deck: 0 tons, 0.0 %
      - Conning Tower: 6 tons, 0.1 %
   Machinery: 869 tons, 20.6 %
   Hull, fittings & equipment: 1,412 tons, 33.5 %
   Fuel, ammunition & stores: 678 tons, 16.1 %
   Miscellaneous weights: 1,250 tons, 29.7 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     5,142 lbs / 2,332 Kg = 399.5 x 6 " / 152 mm shells or 1.1 torpedoes
   Stability (Unstable if below 1.00): 1.11
   Metacentric height 2.1 ft / 0.6 m
   Roll period: 14.3 seconds
   Steadiness   - As gun platform (Average = 50 %): 56 %
         - Recoil effect (Restricted arc if above 1.00): 0.00
   Seaboat quality  (Average = 1.00): 1.03

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.580
   Length to Beam Ratio: 8.00 : 1
   'Natural speed' for length: 19.84 kts
   Power going to wave formation at top speed: 58 %
   Trim (Max stability = 0, Max steadiness = 100): 54
   Bow angle (Positive = bow angles forward): 0.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      21.82 ft / 6.65 m
      - Forecastle (20 %):   13.88 ft / 4.23 m
      - Mid (50 %):      13.88 ft / 4.23 m
      - Quarterdeck (15 %):   13.88 ft / 4.23 m
      - Stern:      13.88 ft / 4.23 m
      - Average freeboard:   14.51 ft / 4.42 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 99.5 %
      - Above water (accommodation/working, high = better): 141.4 %
   Waterplane Area: 13,908 Square feet or 1,292 Square metres
   Displacement factor (Displacement / loading): 141 %
   Structure weight / hull surface area: 70 lbs/sq ft or 340 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 1.09
      - Longitudinal: 1.40
      - Overall: 1.11
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is excellent

1200 tons misc.
    25 tons radio
    25 tons navigation radar
    25 tons acoustics      

[TexanCowboy]

The speed seems high for a tender...but I can live with it. I'd add some armarment, even if only a few AA guns, myself, but each to his own...

[Kaiser Kirk]

I would push the displacement up a bit, as the smallest ports take 5000tons.
I would dispense with the electric generators as harder to service in civilian facilities. I expect 2 shafts would be adequate as well.

I question the speed priorities. The Dash speed is still low enough as to be unable to avoid even old small cruisers, yet eats a great deal of displacement, while the cruise speed is set fairly low (which may be for consistancy).  In a similar vessel, I went with a lower top speed, but a higher cruise speed. Dedicated warships can catch her, but AMC and subs can't.