JL-2
Encyclopedia
The JL-2 is a Chinese
second-generation intercontinental-range submarine-launched ballistic missile
(SLBM) which has a two-stage, solid–liquid-fuelled propulsion design. Accurate specifications of the new missile are hard to obtain and substantiate due to the secretive nature of the program. However, the missile is thought to be able to deliver its payload(s) up to a range of 7,200 km (4,500 miles) to 8000 km (4,971 mi) and could carry either single or multiple warheads (conventional or nuclear).
ballistic missile. As such, it shares many features of DF-31 missile such as its operational range. There has been a debate among Western analysts on whether the JL-2 missile is capable of carrying multiple warheads (MIRVs
) because China has never fielded any submarine-based MIRVs before. Most analysts within the U.S. intelligence community believe that the missile can carry only a single warhead (conventional or nuclear). Other analysts such as Jane's Defence asserted that the missile can deliver 3 to 4 MIRVs, each with a yield of 90 kt or a single warhead of 25 to 1,000 kt yield. The JL-2 SLBMs are carried on the new Chinese Type 094 (Jin-class) submarine. It replaces the earlier first-generation JL-1
SLBM which were primarily deployed by the older Type 092 (Xia-class) nuclear submarine.
The JL-2 missile is expected to provide China with its first credible sea-based nuclear deterrent. The expected operational range of the missile (up to 8,000 km or 5,000 miles) will allow it to reach Alaska
, Hawaii
, Guam
, Russia
, and India
but not the continental United States from Chinese littoral waters (Bohai Sea
or South China Sea
).
The general designer of the missile is Huang Weilu [黄纬禄] (1916–). The first sea launch of the JL-2 was reported to have taken place mid January 2001 from a modified Golf class
submarine. The missile is expected to enter initial operational capability within the 2009–2010 timeframe.
)
At 10:20 AM, 22nd Dec, 2002, the first ship of a new type of SSBN was formally launched by China in Huludao, which now is known as Type 094 (Jin-Class). But, its SLBM was, just as convention, lagging behind. JL-2 has three subtypes, the initial experimental one, the "Jia" (甲, Chinese literally means "The First", or "I"), and the "Yi" (乙, Chinese literally means "The Second", or "II"). The codes for "Jia" and "Yi" are JMA and JMB, respectively. The tests happened of JMA/B are listed like below:
named Wang Zhenhua (王振华) proposed a new theory typically for the JL-2 SLBM, called "(Free) Relaxation into Trajectory" (自由入轨). This theory was incorrectly translated and contains enormous technical and physical inaccuracies and no understanding of the rocket equation.
Based on this theory, JL-2 only needs two stages to achieve its intercontinental status instead of three. Conventionally, any type of ICBMs has three phases to finish its flight: (i) the boost phase, (ii) the mid-course phase, and (iii) the terminal phase. Wang's idea is to combine the first and the second phases into one, the passive-boost phase (助推段). Plus the final atmospheric reentry
phase, therefore, in total the JL-2's trajectory only has two phases and two stages.
The first phase is based on the first solid-fueled rocket engine (first stage). The first stage passively launches the missile out of the atmosphere, and accelerates it into a speed in between the first (7.9 km/s) and second (11.2 km/s) escape velocities
. When the missile is in this transition state
, the first stage booster sheds off, and the missile automatically adapts its "free" trajectory and further reaches its maximum altitude (without a constant velocity); the dominating force here is just the earth's gravity
. The second stage engine (liquid-fueled) then starts working.
Normally, an SLBM has three stages. Such design simplifies the structure of the missile and largely reduces missile's overall weight by reducing one stage. Additionally, it increases the atmospheric reentry velocity, which leads to more difficult interception, such as, by the NMD
.
People's Republic of China
China , officially the People's Republic of China , is the most populous country in the world, with over 1.3 billion citizens. Located in East Asia, the country covers approximately 9.6 million square kilometres...
second-generation intercontinental-range submarine-launched ballistic missile
Submarine-launched ballistic missile
A submarine-launched ballistic missile is a ballistic missile capable of delivering a nuclear warhead that can be launched from submarines. Modern variants usually deliver multiple independently targetable reentry vehicles each of which carries a warhead and allows a single launched missile to...
(SLBM) which has a two-stage, solid–liquid-fuelled propulsion design. Accurate specifications of the new missile are hard to obtain and substantiate due to the secretive nature of the program. However, the missile is thought to be able to deliver its payload(s) up to a range of 7,200 km (4,500 miles) to 8000 km (4,971 mi) and could carry either single or multiple warheads (conventional or nuclear).
Introduction
JL-2's design is based on the mobile land-based DF-31DF-31
The Dong Feng 31 is a long-range, road-mobile, three stage, solid propellant intercontinental ballistic missile in the Dongfeng missile series developed by the People's Republic of China. It is designed to carry a single 1,000kt thermal nuclear warhead. It is a land-based variant of the submarine...
ballistic missile. As such, it shares many features of DF-31 missile such as its operational range. There has been a debate among Western analysts on whether the JL-2 missile is capable of carrying multiple warheads (MIRVs
Multiple independently targetable reentry vehicle
A multiple independently targetable reentry vehicle warhead is a collection of nuclear weapons carried on a single intercontinental ballistic missile or a submarine-launched ballistic missile . Using a MIRV warhead, a single launched missile can strike several targets, or fewer targets redundantly...
) because China has never fielded any submarine-based MIRVs before. Most analysts within the U.S. intelligence community believe that the missile can carry only a single warhead (conventional or nuclear). Other analysts such as Jane's Defence asserted that the missile can deliver 3 to 4 MIRVs, each with a yield of 90 kt or a single warhead of 25 to 1,000 kt yield. The JL-2 SLBMs are carried on the new Chinese Type 094 (Jin-class) submarine. It replaces the earlier first-generation JL-1
JL-1
The Julang-1, also known as the JL-1 and in US nomenclature as the CSS-N-3, is China's first submarine launched nuclear ballistic missile.-History:...
SLBM which were primarily deployed by the older Type 092 (Xia-class) nuclear submarine.
The JL-2 missile is expected to provide China with its first credible sea-based nuclear deterrent. The expected operational range of the missile (up to 8,000 km or 5,000 miles) will allow it to reach Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
, Hawaii
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...
, Guam
Guam
Guam is an organized, unincorporated territory of the United States located in the western Pacific Ocean. It is one of five U.S. territories with an established civilian government. Guam is listed as one of 16 Non-Self-Governing Territories by the Special Committee on Decolonization of the United...
, Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
, and India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
but not the continental United States from Chinese littoral waters (Bohai Sea
Bohai Sea
Bohai Sea , also known as Bohai Gulf, Bohai, or Bo Hai, is the innermost gulf of the Yellow Sea on the coast of Northeastern and North China. It is approximately 78,000 km2 Bohai Sea , also known as Bohai Gulf, Bohai, or Bo Hai, is the innermost gulf of the Yellow Sea on the coast of...
or South China Sea
South China Sea
The South China Sea is a marginal sea that is part of the Pacific Ocean, encompassing an area from the Singapore and Malacca Straits to the Strait of Taiwan of around...
).
The general designer of the missile is Huang Weilu [黄纬禄] (1916–). The first sea launch of the JL-2 was reported to have taken place mid January 2001 from a modified Golf class
Golf class submarine
Project 629, also known by the NATO reporting name of Golf class, were diesel electric ballistic missile submarines of the Soviet Navy. They were designed after six Zulu class submarines were successfully modified to carry and launch Scud missiles...
submarine. The missile is expected to enter initial operational capability within the 2009–2010 timeframe.
History
The whole JL-2 project lasts roughly about one decade, till present. The original designation of the project was so-called "New DongFeng Goes Undersea" ("新东风下海"), by the COSTIND and CMC. The project was co-held by the First and Second Research Institutes of the Ministry of Aerospace Industry (defunct, see CNSAChina National Space Administration
The China National Space Administration is the national space agency of the People's Republic of China responsible for the national space program. It is responsible for planning and development of space activities...
)
At 10:20 AM, 22nd Dec, 2002, the first ship of a new type of SSBN was formally launched by China in Huludao, which now is known as Type 094 (Jin-Class). But, its SLBM was, just as convention, lagging behind. JL-2 has three subtypes, the initial experimental one, the "Jia" (甲, Chinese literally means "The First", or "I"), and the "Yi" (乙, Chinese literally means "The Second", or "II"). The codes for "Jia" and "Yi" are JMA and JMB, respectively. The tests happened of JMA/B are listed like below:
- JMA: Land-based tests, 3 times; launched from a base in Shanxi, most likely the Taiyuan Satellite Launch CenterTaiyuan Satellite Launch CenterThe Taiyuan Satellite Launch Center also known as Base 25 , is a People's Republic of China space and defence launch facility . It is situated in Kelan County, Xinzhou Prefecture, Shanxi Province and is the second of three launch sites having been founded in March 1966 and coming into full...
or nearby; 2001; successful. - JMB: Sea-based, 8 times; launched near DalianDalianDalian is a major city and seaport in the south of Liaoning province, Northeast China. It faces Shandong to the south, the Yellow Sea to the east and the Bohai Sea to the west and south. Holding sub-provincial administrative status, Dalian is the southernmost city of Northeast China and China's...
, by the modified Golf-class diesel-powered ballistic missile submarineBallistic missile submarineA ballistic missile submarine is a submarine equipped to launch ballistic missiles .-Description:Ballistic missile submarines are larger than any other type of submarine, in order to accommodate SLBMs such as the Russian R-29 or the American Trident...
; 2002; successful.
JL-2
- NATO code: CSS-N-4Mod0
- Structure: 2 stages
- Fuel: 1st: solid-fueled; 2nd: liquid-fueled
- Operational range: 8,600 km (max)
- Mass: 23+ t
- Warhead: Single or MIRV; 3~4 Nuclear 250 kt /thermo
- Guidance system: Inertial + stellar update
- Accuracy: 80+ CEP
- Platform: SSBN
- Designer: The First and Second Research Institutes of the Ministry of Aerospace Industry
- Manufacturer: CASTC
JL-2 "Jia"
- NATO code: CSS-N-4ModI
- Structure: 2 stages
- Fuel: 1st: solid-fueled; 2nd: liquid-fueled
- Operational range: 12,000 km
- Mass: 23+ t
- Warhead: Single or MIRV; 6~8 Nuclear 250 kt /thermo
- Guidance system: Inertial + stellar update
- Accuracy: 80+ CEP (with satellite guidance)
- Platform: SSBN
- Designer: The Second Research Institute of the Ministry of Aerospace Industry
- Manufacturer: CASTC
JL-2 "Yi"
- NATO code: CSS-N-4ModII
- Structure: 2 stages
- Fuel: 1st: solid-fueled; 2nd: liquid-fueled
- Operational range: 14,000 km
- Mass: 23+ t
- Warhead: Single or MIRV; ~10 (max) Nuclear 250 kt /thermo
- Guidance system: Inertial + stellar update
- Accuracy: 40+ CEP (with satellite guidance)
- Platform: SSBN
- Designer: The Second Research Institute
- Manufacturer: CASTC
New theory
In late 1980s and 1990s, an academician of the Chinese Academy of EngineeringChinese Academy of Engineering
The Chinese Academy of Engineering is the national academy of the People's Republic of China for engineering. It was established in 1994 and is an institution of the State Council of China...
named Wang Zhenhua (王振华) proposed a new theory typically for the JL-2 SLBM, called "(Free) Relaxation into Trajectory" (自由入轨). This theory was incorrectly translated and contains enormous technical and physical inaccuracies and no understanding of the rocket equation.
Based on this theory, JL-2 only needs two stages to achieve its intercontinental status instead of three. Conventionally, any type of ICBMs has three phases to finish its flight: (i) the boost phase, (ii) the mid-course phase, and (iii) the terminal phase. Wang's idea is to combine the first and the second phases into one, the passive-boost phase (助推段). Plus the final atmospheric reentry
Atmospheric reentry
Atmospheric entry is the movement of human-made or natural objects as they enter the atmosphere of a celestial body from outer space—in the case of Earth from an altitude above the Kármán Line,...
phase, therefore, in total the JL-2's trajectory only has two phases and two stages.
The first phase is based on the first solid-fueled rocket engine (first stage). The first stage passively launches the missile out of the atmosphere, and accelerates it into a speed in between the first (7.9 km/s) and second (11.2 km/s) escape velocities
Escape velocity
In physics, escape velocity is the speed at which the kinetic energy plus the gravitational potential energy of an object is zero gravitational potential energy is negative since gravity is an attractive force and the potential is defined to be zero at infinity...
. When the missile is in this transition state
Transition state
The transition state of a chemical reaction is a particular configuration along the reaction coordinate. It is defined as the state corresponding to the highest energy along this reaction coordinate. At this point, assuming a perfectly irreversible reaction, colliding reactant molecules will always...
, the first stage booster sheds off, and the missile automatically adapts its "free" trajectory and further reaches its maximum altitude (without a constant velocity); the dominating force here is just the earth's gravity
Earth's gravity
The gravity of Earth, denoted g, refers to the acceleration that the Earth imparts to objects on or near its surface. In SI units this acceleration is measured in metres per second per second or equivalently in newtons per kilogram...
. The second stage engine (liquid-fueled) then starts working.
Normally, an SLBM has three stages. Such design simplifies the structure of the missile and largely reduces missile's overall weight by reducing one stage. Additionally, it increases the atmospheric reentry velocity, which leads to more difficult interception, such as, by the NMD
National Missile Defense
National missile defense is a generic term for a type of missile defense intended to shield an entire country against incoming missiles, such as intercontinental ballistic missile or other ballistic missiles. Interception might be by anti-ballistic missiles or directed-energy weapons such as lasers...
.
External links
- JL-2 (CSS-NX-4) – China Nuclear Forces from Globalsecurity.org
- JL-2 from Mark Wade's Encyclopedia Astronautica
- launch article from Armscontrolwonk
- Chinese Defence Today – JL-2 Submarine Launched Ballistic Missile
- Images of JL-2 Launch