Schulka-class Coastal Submarine
In September 1939, the Russians had the largest submarine fleet in the world with some 150 boats (Italy and the United States had 107 and 100, respectively). However, a large number of these boats were small, short-ranged coastal patrol boats and the Russians had to maintain four separate fleets, which made this advantage rather less meaningful.
One of the more numerous of the Russian submarines was the Schulka-class (comprising some 97 boats of series III, V and X). More than half of these (53) were the X and Xbis submarines, which started service in 1936. The X/Xbis boats had an endurance of some 40 days, which made them capable of ocean operations. Some 30 boats of the Schulka-class were sunk during the war, with the rest serving until the 1950’s (and eleven Xbis boats lasting until the 1960’s). One typically Russian feature was the use of an enclosed and heated conning tower.
The Xbis has a crew of 40. It mounts four 21” torpedo tubes stern and two aft. A pair of 45mm guns and one 7.62mm MG are provided for air defense. The engines burn 155 gallons of diesel fuel per hour of routine usage. The Xbis can travel 7,060 miles at 8 mph surfaced and 140 miles at 2.3 mph submerged.
Xbis
Subassemblies: Light Corvette chassis with Sub option
+8; sealed Medium Secondary superstructure [Body:T] +3; two full-rotation
Medium Weapon open mounts.
Powertrain: 2¥597-kW marine diesel engines with 2¥597-kW
water screws and 19,000-gallon standard tanks; 2¥298-kW electric motors
with 14.5 million-kWs batteries†.
Occupancy: 20 CS Body, 5 CS Sup Cargo:
1,235 Body, 117 Sup, 1.8 OM
Armor
Body: 4/40
Sup: 4/40
OM: 0/0
Weaponry
4¥533mm Torpedo Tubes [Body: F] (*).
2¥533mm Torpedo Tubes [Body: B] (*).
50mm Long TG/45mm [OM1:F] (200).
50mm Long TG/45mm [OM2:F] (200).
* Ten torpedoes are carried.
Equipment
Body: Autopilot; backup driver controls; 693-VSP bilge; 15¥bilge
pumps†; 20¥bunks; 100-VSP cargo holds; 50-man environmental control†;
10¥fire extinguishers†; 40-man-days life support†; navigation instruments;
precision navigation instruments; 2,565-man/days of provisions; 2-mile
passive sonar. Sup: Navigation instruments; 1¥20’ 15¥ periscopes;
2¥very large radio receivers and transmitters; searchlight. OM1&2:
Universal mounts.
† Limited access.
Statistics
| Size: 193’¥20’¥36’ | Payload: 100 tons | Lwt: 611 tons |
| Volume: 5,160 | Maint.: 10 hours | Price: $390,000 |
HT: 10
HP: 36,000 [Body], 750 [Superstructure], 75 [Each Open Mount]
| wSpeed: 17 | gAccel: 0.1 | gDecel: 0.5(0.6) | gMR: 0.05 | gSR: 4 | Draft: 14' |
| uSpeed: 10 | gAccel: 0.05 | gDecel: 0.3(0.4) | gMR: 0.05 | gSR: 4 | uDraft: 36' |
Design Notes
The 708-ton historical submerged weight was used for underwater performance
calculations. Design wSpeed was 15 mph and uSpeed was 8.5 mph; the historical
figures were used instead.
A 7.62mm AA gun (Ground LMG) was frequently carried on a pintle mount on the conning tower.
Variants
The four series III boats (1931) were just slightly smaller at 704
tons. They could reach 14 mph surfaced, using a pair of 511-kW engines.
Surfaced range was only 3,750 miles, as it carried less than half the fuel
of the later subs. It also had a patrol duration of only 20 days. It carried
one less 45mm gun and one more LMG. Crew was 35.
Nineteen series V boats (1933) were constructed. They were 1 mph slower; range was 7,700 miles.
The 21 Vbis and Vbis2 boats (1935) reverted to the 511-kW engines and the LMG was normally not carried. Performance was the same as the series V boats, despite displacing 749 tons.