Insect Class Mine Warfare Vessel laid down 1923
Vessels-
K.D.M. Humelbi
K.D.M. Hveps
K.D.M. Gedehams
Displacement:
760 t light; 789 t standard; 910 t normal; 1,003 t full load
Loading submergence 116 tons/feet
Dimensions:
240.00 ft x 28.00 ft x 10.00 ft (normal load)
73.15 m x 8.53 m x 3.05 m
Armament:
2 - 4.72" / 120 mm guns
4 - 2.24" / 57 mm AA guns
8 - 0.51" / 13 mm guns
Weight of broadside 129 lbs / 58 kg
Armour:
Main gun shields 1.00" / 25 mm, AA gun shields 0.50" / 13 mm, Light gun shields 0.50" / 13 mm
Conning tower 0.50" / 13 mm
Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 8,922 shp / 6,656 Kw = 24.00 kts
Range 6,000nm at 12.00 kts
Complement:
82 - 107
Cost:
£0.238 million / $0.952 million
Distribution of weights at normal displacement:
Armament: 16 tons, 1.8 %
Armour: 5 tons, 0.6 %
Belts: 0 tons, 0.0 %, Armament: 4 tons, 0.5 %, Armour Deck: 0 tons, 0.0 %
Conning Tower: 1 tons, 0.1 %, Torpedo bulkhead: 0 tons, 0.0 %
Machinery: 298 tons, 32.8 %
Hull, fittings & equipment: 341 tons, 37.4 %
Fuel, ammunition & stores: 150 tons, 16.5 %
Miscellaneous weights: 100 tons, 11.0 %
Metacentric height 0.8
Remarks:
Hull space for machinery, storage & compartmentation is cramped
Room for accommodation & workspaces is adequate
Ship has slow, easy roll, a good, steady gun platform
Estimated overall survivability and seakeeping ability:
Relative margin of stability: 1.01
Shellfire needed to sink: 636 lbs / 288 Kg = 12.1 x 4.7 " / 120 mm shells
(Approx weight of penetrating shell hits needed to sink ship excluding critical hits)
Torpedoes needed to sink: 0.4
(Approx number of typical torpedo hits needed to sink ship)
Relative steadiness as gun platform: 70 %
(Average = 50 %)
Relative rocking effect from firing to beam: 0.25
Relative quality as seaboat: 1.01
Hull form characteristics:
Block coefficient: 0.474
Sharpness coefficient: 0.34
Hull speed coefficient 'M': 7.57
'Natural speed' for length: 15.49 kts
Power going to wave formation at top speed: 64 %
Trim: 69
(Maximise stabilty/flotation = 0, Maximise steadiness/seakeeping = 100)
Estimated hull characteristics & strength:
Underwater volume absorbed by magazines and engineering spaces: 131.7 %
Relative accommodation and working space: 105.1 %
(Average = 100%)
Displacement factor: 110 %
(Displacement relative to loading factors)
Relative cross-sectional hull strength: 0.91
(Structure weight / hull surface area: 46 lbs / square foot or 223 Kg / square metre)
Relative longitudinal hull strength: 2.32
(for 11.10 ft / 3.38 m average freeboard, freeboard adjustment 1.72 ft)
Relative composite hull strength: 1.00
The "Insect" class of mine warfare vesselsare capabale of placing and clearing minefields, and carry 100 mines.