There are three propellers: the starboard and midship ones turn clockwise, port turns
counterclockwise. Shafts are 20 m long. Screw velocity is between 120 and 180 rpm.
Propellers are fixed, 57-m diameter and weigh 50 tonnes, each has four 7-tonne blades
fixed by 9 bolts (16-tonne torque applied); inspection wells allow them to be examined
while in operation. Four spare blades are carried; diving and other equipment is aboard so
a blade may be replaced at sea, each operation takes from 1 to 4 days (three such changes
have been necessary on Rossiya icebreakers since 1985). A propulsive effort of 480 tonnes
can be delivered with 1843 MW (25,000 shaft horsepower) from each screw (total 55.3
MW [75,000 shaft horsepower]). Power can be controlled at a rate of 1% per second.
Maximum speed is 22 knots (40 km/h); full speed in open water is 19.5 knots (35 km/
h); breaking ice 23 m thick can be done at 3 knots (5.5 km/h) continuously. Maximum ice
thickness that can be penetrated while navigating is estimated as 5 m; individual ridges
estimated at 9-m thick have been broken through.
The helm controls one rudder, which turns 35 either way, operated by four hydraulic
cylinders powered by one of two pumps. It is protected by an ice horn for moving astern.
Steering may also be provided by directing air jets of the bubbling system (comparable to
use of bow thrusters).
Auxiliary power is available from three diesel generating sets; one MW and two 250
kW.
Anchors: two 7-tonne anchors with 300 m of chain each, and four ice anchors.
Four deck cranes are aboard, the largest pair can lift 16 tonnes each.
Sea water distillation: two vacuum stills can supply 5 m3 of fresh water per hour each
(240 m3 per day).
Differential ballast tanks are situated fore and aft, and athwart the ship; the pumps are
capable of moving 1 m3 of water per second.
Ship has 1280 compartments (cabins, storage areas, machine rooms, etc.).
Sufficient provisions and supplies can be carried to operate for 7 months.
Safety equipment includes: one launch, two fully enclosed lifeboats, and 18 inflatable
life rafts.
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