Type 039A submarine

The  Type 041 submarine (NATO reporting name Yuan-class) is a class of diesel-electric submarine in China's People's Liberation Army Navy. It is China's first AIP powered submarine. This class was first launched at Wuhan Shipyard and is the successor of the Type 039. The official Chinese designation is 039A as the ship is based on the 039 class, but as the 039A has very little resemblance to the 039 it is commonly referred to as the Type 041.

Design
The Type 041 inherits the tail design of the Type 039 (NATO codename: Song class) with four diving planes and a single large shaft. The teardrop shaped hull and large sail suggest heavy Kilo influence. The teardrop shape also suggests a pressurized double hull design inherited from the Kilo. A pair of foreplanes are positioned in the middle of the sail. The submarine is equipped with indigenously developed cabin-raft (shock absorbers) system that helped to reduce noise level by over 35dB. Additionally, the submarine is covered with rubber anti-sonar protection tiles to reduce the risk of detection. A new improved "C" variant was also launched.

Weapons
The Type 041 has six 533 mm torpedo tubes. These can be used to launch indigenous as well as Russian-made torpedoes. The general designer of the torpedo and missile launching system is Mr. Sun Zhuguo (孙柱国, 1937-). The Type 041 is also believed to be capable of launching YJ-8X (C-80X) series anti-ship missiles. The missile uses inertial + terminal active radar guidance. It carries a 165 kg time-delayed semi-armour-piercing high-explosive warhead, with a maximum range of 80~120 km and speed of Mach 0.9.

The Type 041 is also capable of firing the CY-1 ASW missile under water, but the status of the missile is in question because nothing is heard about its production. The CY-1 ASW missile has a maximum range of 18 km (10 nm), and when using A244 or Mark 46 torpedo as a payload.

This class is designed to replace the aging Romeo and Ming Class SSKs that previously formed the backbone of the PLAN conventional submarine force. At least seven boats have been commissioned as of 2013 by the PLAN.

Sensors
China was known to have imported the Thales TSM 2233 ELEDONE / DSUV-22 and Thales TSM 2255 / DUUX-5 from France during the 1980s and early 1990s. It also has access to a wide range of modern Russian sonar systems (MG-519 MOUSE ROAR, MGK-500 SHARK GILL) through its purchase of the Kilo Class. Comparable systems are expected to be installed for the Type 041.

The Type 041 is likely to be fitted with a comparable surface/air search radar similar to the MRK-50 SNOOP TRAY, a commercial navigation radar like a Furuno unit observed on a number of SONG class and ESM system is comparable to the Type 921-A.

Propulsion
Contrary to many erroneous claims circulated on the internet by domestic Chinese military enthusiasts, the rumored pump-jet propulsion system is not used on this submarine, because that system is still under development. According to the official academic journals published in China, compared to the seven-bladed propeller currently used, the prototype of the indigenously-developed pump-jet can reduce noise level by 7 dB at 6 knots or 10 - 12 dB at 11 knots. But the system still needs further testing, and the current rumor that the pump-jet is planned for later units of this class is highly unlikely. Diesel engines are used for conventional propulsion; this class is the first boat in the Chinese inventory that can achieve full electrical propulsion, which greatly reduces radiation noise. The same all-electric propulsion design is also modified for use on the Chinese navy's Type 093 submarine and Type 094 submarine. The general designer of the all-electric propulsion systems used in these boats is Professor Ma Weiming (马伟明) of China's Naval Engineering University. (Ma, born in Yangzhong in 1960, obtained his Ph.D. from Tsinghua University in 1996.)

According to the Chinese newspaper Science and Technology Daily (科技日报), this 041 class is equipped with an air-independent propulsion system developed by the 711th Research Institute of the China Shipbuilding Heavy Industry Group Corp. (中国船舶重工集团公司第七一一研究所), referred as a "specialized engine" in official Chinese sources. The 711th Institute was founded in April 1963, but it was not until more than a decade later, in 1975, that it ventured into the field of air-independent propulsion systems by establishing an office for a "specialized engine," setting up a team of about a dozen researchers. By June 1996 that team had developed into the "specialized engine engineering research center"; by 2008 there were more than a hundred researchers. In 1998, the first experimental sample was built and a decade later and after a dozen technological breakthroughs, a wide range of matured versions became commercially available and the newest diesel-electric submarine in Chinese navy became the first customer. Although the official Chinese source had not mentioned the exact class of the submarine, it is generally accepted that the class is no other than Type 041 Yuan class, since it is the newest conventional powered submarine in the Chinese navy. The engine is built by Shanghai Qiyao Propulsion Technology Ltd. (上海齐耀动力技术有限公司), a wholly owned subsidiary of the 711th Institute (中国船舶重工集团公司第七一一研究所).

However, the Chinese source failed to mention the exact type of air-independent propulsion system had been installed, but the developer offered a selection ranging from 20 kW to 100 kW (rate for single unit). Recent rumors stated that the boat utilize a Stirling cycle engine, but this cannot be confirmed. It is also unclear if the incorporation of air-independent propulsion system has become the standard or just for evaluation purposes. Since the air-independent propulsion systems onboard western submarines usually rate at 150 kW to 300 kW, so it is safe to assume that similar systems onboard Chinese submarines would also be consisted of at least two units just like its western counterpart.

S20
At IDEX-2013, China revealed a scaled-down version of Type 041 submarine designated as S20, specially intended for export. The main difference between S20 and Type 041 is that the AIP system on the original Type 041 is deleted, but can be available and easily integrated due to modular design of S20, if potential customers choose to purchase AIP systems separately. Due to its modular design, a variety of sensors and weapons can also be easily adopted up on customers' requests. Specifications of S20:
 * Structure: double hulled
 * Length: 66 meter
 * Beam: 8 meter
 * Draft: 8.2 meter
 * Surface displacement: 1850 tons
 * Submerged displacement: 2300 tons
 * Maximum speed: 18 knots
 * Cruise speed: 16 knots
 * Range: 8000 nm @ 16 kts
 * Endurance: 60 days
 * Crew: 38 total
 * Maximum depth: 300 meters

Potential exports of the S20

 * The Bangladesh navy is negotiating for a order of 2 yaun class submarines.
 * Pakistan is said to be in talks for six submarines rumored to be Yuan class. The deal is said to be signed by the end of 2014.

Variants
A total of four variants of Type 039A have been developed by the first half of 2014, and they are listed here in chronological order based on their public debut:
 * Type 039A: Original Yuan class. The most obvious external visual difference between Type 039A and its predecessor Type 039/039G Song class submarine is in the conning tower. The conning tower of Type 039A is similar to that of Type 039G, but the tower lacks the fin-shaped extrusion on the rear section of the conning towers of both the Type 039 and the Type 039G.


 * Type 039AG: This second member of Type 039A series is frequently but erroneously identified as its development, Type 039B, because externally, the two version looks the same above waterline. The only difference lies below the waterline, which is not readily observed, and it's believed that all Type 039AG have been converted to Type 039B. The most obvious external visual difference between Type 039AG along with its development Type 039B and earler Type 039A submarine is also in the conning tower: the shape edge at the top of conning tower of Type 039A is replaced with smooth round shape transition. In addition, there is a bulge in the middle of the smooth transition in the forward portion of the conning tower housing some kind of sensor, and this is a new feature earlier Type 039A lacks.


 * Type 039B: This third member of Type 039A series looks identical to earlier Type 039AG from which it is developed from. The biggest difference between Type 039B and Type 039AG is that Type 039B has incorporated flank sonar array, which was subsequently retrofitted on Type 039AG and some earlier boats. This difference, however, is not readily observable because the flank array is installed at the lower portion of the hull. It was only in the early 2010's when a Type 039B built by Shanghai Changxing (长兴) Shipyard exposed in the berth, when the flank array of Type 039B became publicized, thus distinguish the type from earlier Type 039AG that lacked the flank sonar.


 * Type 039C: The fourth variant of the Yuan has been first publicized in December 2013, with a modified hull and redesigned conning tower with extrusion at the root of the conning tower in both the bow and stern direction, similar to that of conning tower of Virginia-class submarine. In addition, the bulge housing unknown sensor on board Type 039B in the forward section of the top edge of the conning tower is absent on the new boat launched in April 2014, but there are three white lines at the top of edge of the conning tower on both sides, presumably for environmental sensors. This new boat is claimed to be Type 039C.