China - Romeo Class Diesel-Electric Submarine

Under the agreement between Beijing and Moscow on 4 February 1959, the Soviet Union agreed to transfer the technologies of its Project 633 (NATO codename: Romeo class) diesel-electronic torpedo submarine and Project 629  (NATO codename: Golf class) diesel-electric missile submarine to China. The two submarines were to be built in China locally as Type 6633 (later known as Type 033) and Type 6631 (later known as Type 031) respectively The production was to use Soviet-supplied kits initially, and then gradually increase the indigenous elements until China could build the submarines independently.

As a result of the break-up of the Sino-Soviet relation, Moscow withdrew all its advisers and technical assistance in 1960. This had resulted in the temporary stop of the submarine building project. It took China several years to resume the production using domestic components. The first Type 033 submarine was launched at Shanghai-based Jiangnan Shipyard in December 1965, but various technical problems carried on until the early 1970s. A total of 84 boats had been built before the production finally stopped in 1984.

The Type 033 is generally regarded as an ageing design, only suitable for coastal defence and patrol duties. The submarine is very noisy, and incapable of operating deep oceans far from its homeport, and is very noisy. Most of these submarines were retired from active duty throughout the 1990s, with only few remaining in service for training and surveillance purposes. A number of Type 033 submarines have been mothballed in caves for reserve, and can be restored to service condition in short period. China sold four Type 033 submarines to North Korea, and also supplied kits for local production. Egypt also operated four Type 033 submarines it imported from China in the 1980s. China also developed its Type 035 (Ming class) submarine based on the Type 033/Romeo class design.

Design

The Type 033 is not merely a clone of the original Romeo class. Instead, considerable improvements were made at both design and later production stages. The Type 033 has eight torpedo tubes, in contrast to the six tubes on Romeo class. Also the Type 033 has a slightly increased displacement while remains same underwater speed. By increasing the fuel capacity, the maximum range and self-retaining capability of the Type 033 is twice as much as those of Romeo class. Other improvements include an improved sonar, and a water-cooling system for the battery array.

The Type 035 has eight 533mm torpedo tubes (6 bow, 2 stern), and carries a total of 14 torpedoes in tubes and storage racks. Alternatively the submarine can carry 28 mines in its tubes. The Yu-4 (SAET-60) is a passive homing torpedo designed to attack surface targets up to 15km at a speed of 40 knots. The high-explosive warhead weights 400kg. The Yu-1 is a Chinese copy of the Russian Type 53-51, which was designed to attack surface targets with a maximum range of 9.2km at a speed of 39 knots, or 3.7km at 51 knots. The high-explosive warhead weights 400kg.

The Type 033 is fitted with Hercules or Tamir-5 bow-mounted, high-frequency sonar for active/passive search and attack. Later variants are also fitted with a Sintra DUUX 5 low frequency sonar for passive ranging and intercept. The submarine has an I-band surface search radar (NATO code-name: Snoop Tray). Unconfirmed reports indicated that latest modification on some Type 033 boats included removing weapon systems to accommodate surveillance and electronic intelligence (ELINT) equipment for special reconnaissance missions.

The Type 035 is powered by a diesel-electric arrangement, consisting of 2 Type 37D diesel rated at 4,000hp (2.94MW), with 2 alternators and 2 shafts.

Type 033G (Wuhan-A Class)

In 1976, No.701 Institute (now Wuhan Ship Development and Design Institute) experimentally added the YJ-8 (C-801) anti-ship missile system and its associated Type 358G fire-control radar to the Type 033 submarine. Three missile launcher containers were installed on each side of the sail, with the fire-control radar was located behind the sail. Design of the new submarine designated Type 033G was completed in 1978, and the construction of the first boat (pennant number 351) began in 1980 at Wuchang Shipyard in Wuhan. The submarine was delivered to the PLA navy in October 1983, and was codenamed Wuhan-A class by Western intelligence.

In early 1985, Boat 351 carried out three rounds of live fire test of the YJ-8 missile, with all tests being successful. In late 1980s, the designer studied to reduce the submarine’s underwater noise and the detection range of its sonar. The design of the submarine was finalised in 1986. This variant was known as Wuhan-A class by Western intelligence.

A major weakness with the Type 033G is the fact that the submarine cannot launch its missiles from underwater. To launch its six YJ-8 missiles, the submarine must fully surface, with its speed less than 8 knots. The six missiles can be launched within 6~7 minutes. This seriously limited the submarine’s effectiveness and survivability in real combat. As a result, the submarine served as an experiment, with no subsequent unit built. Boat 351 may have been out of service since the late 1990s.