WesWorld

GB 1 Class Submarine Chaser

GB-1 to -6 in service

Dimensions 118x20x4.6
Displacement: 62 tons
Armament: 1x40mm forward, 2x20mm 4x13.7 cal mg, 12 D.C.
Machinery: 4x 800 hp petrol motors
speed 24 knots
Equipment: Radio (W/T), hydrophone, sounding set

GB-7 Class Submarine Chaser

These are licensed copies of the Bharati A-45 class ASW launch, and happen to represent the largest warships ever built in Hedjaz.

GB-7, laid down 1941
GB-8, laid down 1941


Displacement:
195 t light; 203 t standard; 220 t normal; 234 t full load

Dimensions: Length overall / water x beam x draught
131.23 ft / 131.23 ft x 19.03 ft x 6.56 ft (normal load)
40.00 m / 40.00 m x 5.80 m x 2.00 m

Armament:
1 - 4.13" / 105 mm guns in single mounts, 35.32lbs / 16.02kg shells, 1934 Model
Dual purpose gun in deck mount
on centreline forward
1 - 1.38" / 35.0 mm guns in single mounts, 1.31lbs / 0.59kg shells, 1934 Model
Anti-aircraft gun in deck mount
on centreline
2 - 0.59" / 15.0 mm guns in single mounts, 0.10lbs / 0.05kg shells, 1934 Model
Machine guns in deck mounts
on centreline, evenly spread, all raised mounts
Weight of broadside 37 lbs / 17 kg
Shells per gun, main battery: 150

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.97" / 50 mm - -
2nd: 0.79" / 20 mm - -
3rd: 0.79" / 20 mm - -

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 1 shaft, 2,440 shp / 1,821 Kw = 20.00 kts
Range 2,000nm at 12.00 kts
Bunker at max displacement = 31 tons

Complement:
28 - 37

Cost:
£0.101 million / $0.403 million

Distribution of weights at normal displacement:
Armament: 5 tons, 2.1 %
Armour: 5 tons, 2.2 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 5 tons, 2.2 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 70 tons, 31.9 %
Hull, fittings & equipment: 100 tons, 45.2 %
Fuel, ammunition & stores: 25 tons, 11.3 %
Miscellaneous weights: 16 tons, 7.3 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
197 lbs / 89 Kg = 5.6 x 4.1 " / 105 mm shells or 0.2 torpedoes
Stability (Unstable if below 1.00): 1.11
Metacentric height 0.5 ft / 0.2 m
Roll period: 11.2 seconds
Steadiness - As gun platform (Average = 50 %): 52 %
- Recoil effect (Restricted arc if above 1.00): 0.23
Seaboat quality (Average = 1.00): 1.05

Hull form characteristics:
Hull has a flush deck
Block coefficient: 0.470
Length to Beam Ratio: 6.90 : 1
'Natural speed' for length: 11.46 kts
Power going to wave formation at top speed: 72 %
Trim (Max stability = 0, Max steadiness = 100): 50
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: 14.83 ft / 4.52 m
- Forecastle (20 %): 8.76 ft / 2.67 m
- Mid (50 %): 8.76 ft / 2.67 m
- Quarterdeck (15 %): 8.76 ft / 2.67 m
- Stern: 8.76 ft / 2.67 m
- Average freeboard: 9.25 ft / 2.82 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 127.5 %
- Above water (accommodation/working, high = better): 92.3 %
Waterplane Area: 1,549 Square feet or 144 Square metres
Displacement factor (Displacement / loading): 111 %
Structure weight / hull surface area: 29 lbs/sq ft or 141 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.84
- Longitudinal: 8.96
- Overall: 1.07
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is adequate

GB-9 Class

These second-hand German patrol boats, laid down in 1935-6, were acquired in 1942. Their low cost and relatively low age, in combination with the effective design, were quite popular with Hedjazi officials.

GB-9 to GB-12 (ex-VP11 to VP14), laid down 1935, refitted 1944-5
GB-13-14 (ex-VP15 to VP16), laid down 1936

VP-11, German Patrol Boat laid down 1934

Displacement: 288 t light; 299 t standard; 337 t normal; 367 t full load

Dimensions: Length overall / water x beam x draught

180.45 ft / 180.45 ft x 18.04 ft x 6.89 ft (normal load) [55.00 m / 55.00 m x 5.50 m x 2.10 m]

Armament:

2 - 3.46" / 88.0 mm guns in single mounts, 20.79lbs / 9.43kg shells, 1934 Model Dual purpose guns in deck mounts on centreline ends, evenly spread, 1 raised mount
2 - 1.46" / 37.0 mm guns (1x2 guns), 1.55lbs / 0.70kg shells, 1929 Model Anti-aircraft guns in deck mount on centreline aft, all raised guns - superfiring
8 - 0.79" / 20.0 mm guns in single mounts, 0.24lbs / 0.11kg shells, 1928 Model Machine guns in deck mounts on side, evenly spread, 4 raised mounts
Weight of broadside 47 lbs / 21 kg
Shells per gun, main battery: 150

Armour:

Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.79" / 20 mm - -
2nd: 0.79" / 20 mm - -
3rd: 0.39" / 10 mm - -

Conning tower: 1.18" / 30 mm

Machinery:

Diesel Internal combustion motors, Geared drive, 2 shafts, 5,598 shp / 4,176 Kw = 25.00 kts
Range 4,000nm at 12.00 kts
Bunker at max displacement = 68 tons

Complement: 39 - 51

Cost: £0.170 million / $0.680 million

Distribution of weights at normal displacement:

Armament: 6 tons, 1.7 %
Armour: 5 tons, 1.4 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 4 tons, 1.1 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 1 tons, 0.4 %
Machinery: 140 tons, 41.7 %
Hull, fittings & equipment: 117 tons, 34.7 %
Fuel, ammunition & stores: 49 tons, 14.5 %
Miscellaneous weights: 20 tons, 5.9 %

Overall survivability and seakeeping ability:

Survivability (Non-critical penetrating hits needed to sink ship): 130 lbs / 59 Kg = 6.3 x 3.5 " / 88 mm shells or 0.2 torpedoes
Stability (Unstable if below 1.00): 1.14
Metacentric height 0.5 ft / 0.1 m
Roll period: 10.8 seconds
Steadiness - As gun platform (Average = 50 %): 60 %
- Recoil effect (Restricted arc if above 1.00): 0.32
Seaboat quality (Average = 1.00): 1.50

Hull form characteristics:

Hull has raised forecastle and transom stern
Block coefficient: 0.525
Length to Beam Ratio: 10.00 : 1
'Natural speed' for length: 15.29 kts
Power going to wave formation at top speed: 72 %
Trim (Max stability = 0, Max steadiness = 100): 40
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: 20.51 ft / 6.25 m
- Forecastle (35 %): 19.69 ft / 6.00 m (8.20 ft / 2.50 m aft of break)
- Mid (50 %): 8.20 ft / 2.50 m
- Quarterdeck (15 %): 8.20 ft / 2.50 m
- Stern: 8.20 ft / 2.50 m
- Average freeboard: 12.34 ft / 3.76 m

Ship space, strength and comments:

Space - Hull below water (magazines/engines, low = better): 154.7 %
- Above water (accommodation/working, high = better): 92.5 %
Waterplane Area: 2,310 Square feet or 215 Square metres
Displacement factor (Displacement / loading): 85 %
Structure weight / hull surface area: 17 lbs/sq ft or 84 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 9.26
- Overall: 0.67
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is adequate
Good seaboat, rides out heavy weather easily

15 tons for hydrophones and sonar
10 tons for depth charges and rails