Dongfeng 5
Official name: Dongfeng 5 (DF-5)
NATO reporting name: CSS-4
Contractor: China Academy of Launch Vehicle Technology (CALT)
Type: ICBM, nuclear-armed
Status: In service
Deployment: Silo or launch pad
Propellant: Unsymmetrical Dimethylhydrazine/Nitrogen Tetroxide mix (UDMH/N2H4)
First-stage motor: YF-21 (four YF-20), rated at 2,785kN
Second-stage motor: YF-22, rated at 720kN
Length: 33m
Body diameter: 3.4m
Launch weight: 183,000kg
Range: 12,000km (DF-5), >13,000km (DF-5A)
Re-entry vehicle mass: ~3,000kg
Warhead: One single 3,000kT
Guidance: Inertial + stellar update
Accuracy: ~1,000m CEP
Launch preparation time: 3~5 hours (launch pad), or 1~2 hours (in silo)
The Dongfeng 5 (DF-5) is the PRC’s first intercontinental ballistic missile (ICBM). The two-stage, liquid-propellant missile has been developed into the Changzheng 2 space launch vehicle (SLV), based on which the entire Changzheng SLV family was developed. the Dongfeng 5 has the longest range (10,000~13,000km) amongst the PRC’s ballistic missiles, capable of reaching the continental United States and Europe. Dongfeng 5 achieved the initial operational capability in the early 1980s, and its improved variant Dongfeng 5A (CSS-4 Mod 2) was deployed in the mid-1990s. It was estimated that the PRC currently deploys about 20 silo-based Dongfeng 5As, which make up the country’s primary nuclear deterrent.
The Dongfeng 5 was designed and developed by the Beijing-based China Academy of Launch Vehicle Technology (CALT, also known as 1st Space Academy). The Capital Aerospace Machinery Corporation (CAMC, previously known as 211 Factory or Capital Machinery Factory), an affiliate of the CALT, fabricates both the Dongfeng 5 ICBM and the Changzheng 2 SLV at its manufacture complex in the south suburb of Beijing. A second Dongfeng 5 fabrication facility known as Sichuan Aerospace Industry Corporation (also known as Base 062) is located in Chengdu, Sichuan Province.
Design
The Dongfeng 5 is a large two-stage rocket powered by a liquid bipropellant, with unsymmetrical dimethylhydrazine (UDMH) as fuel and nitrogen tetroxide (N2H4) as an oxidiser. The first-stage consists of four parallel 75t-thrust YF-20 chambers motors with swinging nozzles. The second-stage utilises a 75t-thrust YF-22 motor with a fixed nozzle, and a swiveling venire motor with four 4.8t-thrust YF-23 chambers, which were designed for steering and sustaining propulsion for a further 190 seconds after the shutting of the main motor, and enabling a wide aiming arc for the re-entry vehicles in the upper atmosphere. The propellant tank of the missile was made of high-strength, lightweight aluminium-cooper alloy. The re-entry vehicle is fitted with a heat shield made of carbon/quartz materials.
The missile uses a computerised inertial guidance system, with an estimated CEP of 1,000~1,500m. The missile carries a single three-megaton thermonuclear warhead designated "506", which is roughly 3,000kg in weight. The improved Dongfeng 5A may have the ability to carry one or more decoys along with the warhead. The PRC is capable of developing the multiple independently-targetable re-entry vehicle (MIRV), and its second-generation warheads introduced in the 1990s are small and light enough for 3~4 to be fitted on a single Changzheng 5, but it is generally believed that neither Dongfeng 5 or Dongfeng 5A possess an MIRV capability. Dongfeng 5 has a maximum range of 9,000~10,000km, and Dongfeng 5A has an extended range of over 13,000km.
The exact number of the missile in deployment remains highly classified, and observer estimations vary significantly, ranging from less than 10 to over 30. According to some reports, by 2008 Dongfeng 5 units in the PLA Second Artillery Corps consisted of three brigades, each operating 6~10 missiles. These units included 801 Brigade (cover designator: 96261 Unit) headquartered in Lingbao City, Henan Province, 804 brigade (cover designator: 96263 Unit) headquartered in Luanchan County of Luoyang City, Henan Province, and 803 Brigade (cover designator: 96311 Unit) headquartered in Jingzhou County of Huaihua City, Hunan Province. All three brigades are believed to have been upgraded with Dongfeng 5A.
Dongfeng 5s in operational service are stored in underground silos and "hot launched" from within the silo. The early variant of Dongfeng 5 required five hours for pre-launch preparation, but this has been reduced to 1~2 hours using a computerised launch control system on Dongfeng 5A. The missile’s liquid-propellant is storable, which allows the missile to be fuelled days before the firing in order to reduce the launch preparation time. The PLA is believed to have constructed a large number of decoy silos in order to enhance the survivability of its Dongfeng 5s.
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| Dongfeng 5: A Dongfeng 5 on the launch pad in the Shuang Cheng Tzu missile centre (Source: Chinese Internet) |
Development
Development of the Dongfeng 5 began in 1965, with the objective of fielding a true intercontinental-range missile system that could reach the Contiguous United States. A whole new range of technologies were developed for the country’s first ICBM, including high-thrust rocket engine, inertial navigation guidance package, flight control, onboard computer, propellant pumping, warhead heat shield, etc. Two Western-trained top PRC rocket scientists, Tu Shou’e and Ren Xinmin, were appointed to lead Dongfeng 5’s overall design and the development of the rocket motor respectively.
The Dongfeng 5 programme suffered from a major setback, when the missile’s first flight test in 1971 and second flight test in 1972 both failed. The PRC premier Zhou Enlai ordered Dongfeng 5 development to be stopped in October 1973. The programme was resumed four years later in September 1977, after the 1st Space Academy introduced a modified design with downgraded performance (<10,000km range). A number of depressed trajectory (DT) flight tests of Dongfeng 5 were successfully carried out between October 1978 and October 1979, but the PRC scientists could not overcome the technical difficulty of the warhead heat shield until late 1979.
The only full-range flight test of the Dongfeng 5, codenamed “580 Mission”, took place in March 1980, with two missiles fired from Jiuquan (Shuang Cheng Tzu) to the target zone in the South Pacific. The PLA Second Artillery Corps began to deploy the Dongfeng 5 in underground silos in 1981, though the missile was not officially certified for design finalisation until December 1986. The missile was revealed to the public of the first time on 1 October 1984, when three Dongfeng 5s were displayed in the National Day military parade in Beijing to celebrate the 35th anniversary of the PRC. The PLA Second Artillery Corps reportedly had deployed four Dongfeng 5 missiles in underground silos by the late 1980s.
Development of an improved variant Dongfeng 5A began in the early 1990s, with the design objective of extending the range to 13,000km. The longer range was achieved by increasing fuel capacity and reducing the weight of the warhead’s heat shield. Other improvements include a modified guidance system for better accuracy, and a redesigned launch system in order to simplify the launch procedure and reduce the launch preparation time. The first flight test using a depressed trajectory took place on 17 June 1993 from the Jiuquan Missile and Space Centre. A second test using an elevated trajectory took place on 26 July 1995 from the Taiyuan (Wuzhai) Missile and Space Centre. Both tests were successful, allowing Dongfeng 5A to enter operational service.
Chronology
With the intermediate-range Dongfeng 3 (CSS-2) and long-range Dongfeng 4 (CSS-3) development both underway, in 1965 the Chinese leaders decided to develop its first true ICBM capable of reaching North America. Technical and operational requirements for Dongfeng 5 ICBM was issued in March 1965. Two U.S.-trained rocket scientists, Tu Shou’e (deputy chief of the 1st Space Academy) and Ren Xinmin, were appointed to lead the development of the missile and its associated liquid-propellant rocket motor respectively. The programme aimed to have the missile ready for first flight test in 1971 and the design finalised in 1973.
Despite the experience learned in the Dongfeng 3 and Dongfeng 4 development, the Dongfeng 5 still proved highly challenging for the PRC. The missile served as the proving ground for a number of missile technologies, including the liquid-propellant rocket motor, inertial navigation guidance package, missile flight control, onboard computer, propellant pumping, warhead heat shield, etc.
To ensure that the missile achieves the required accuracy after flying over a long distance, a new inertial navigation guidance package based on the computer/platform arrangement was developed for the missile. The missile was fitted with the PRC’s first integrated circuits computer. High-strength, lightweight aluminium-cooper alloy was required for the propellant tank, and carbon/quartz materials were required for the heat shield of the warhead.
To ensure that the missile can be deployed in operational service, special care was taken in deciding the missile’s body diameter, the aerodynamic layout, the ratio between the length of the two stages, the heat protection measures on the missile body, and the jettison method of the first-stage.
The Dongfeng 5 development entered the in May 1966. Following a slow start caused by the political impact of the ’Culture Revolution’, Dongfeng 5 programme entered intensive development in 1969 as requested by the Chinese leadership. The programme definition phase began in May 1966. The development of the first-stage rocket motor was completed on 14 June 1969. The design of the missile was completed in June 1970. The ground test of the rocket motor succeeded in November 1970. The first test missile 'Batch-01-Y1' rolled out in June 1971.
The first flight test of the Dongfeng 5 in September 1971 from Shuang Cheng Tzu (Base 20) was only partially successful. Because of the design flaw in the software of the onboard computer, the second-stage of the missile shut down earlier than scheduled, resulting the missile missing its target spot by 565 km. The second missile was launched in November 1972, but two of the four rocket motor failed to ignite, causing an emergent shut down. The same missile was launched again in April 1973 but it exploded in the midair.
Following two failed flight tests, the Chinese Premier Zhou Enlai ordered the suspension of the Dongfeng 5 programme in October 1973. The remaining four missiles of the same design were all converted into the Changzheng 2 space launch vehicles to support the PRC’s space programme. In November 1974, the first Changzheng 2 was launched from the Jiuquan Satellite Launch Centre, carrying a FSW recoverable satellite. The launcher lost control shortly after the launch and was ordered self-destruction, destroying the satellite onboard.
In May 1975, the PLA ordered to resume the Dongfeng 5 development. In September 1977, the PRC leadership approved the full-range flight test of the Dongfeng 5. 1st Space Academy modified the design of the missile’s first stage to improve its reliability. From November 1975 to January 1978, three consecutive launches of the Changzheng 2 were all successful.
The first successful depressed trajectory (DT) flight test of the Dongfeng 5 using the modified Batch-02 design took place in October 1978, and the test was wholly successful. Six subsequent launches carried out between January and October 1979 were all successful. During these tests, the Dongfeng 5 was successfully launched from underground silos, suggesting that the missile was near ready for operational deployment. In November 1979, Dongfeng 5 design team made breakthrough in the warhead heat shield technology.
On 12 February 1980, the Chinese leadership officially approved the full-range (range: 9,000km; apogee: 1,000 km) flight test of the Dongfeng 5. Preparation for the test began in March, including base exercises at the Shuang Cheng Tzu site and ship exercises in the Yellow Sea.
On 18 May 1980 at 10:00:23 local time, a Dongfeng 5 (codename: 580A) was launched from the Shuang Cheng Tzu missile test site. After flying for 29 minutes and 57 seconds over a distance of 9,070km, the missile's re-entry vehicle hit its targeted landing spot ( 7° 42' 23'' S, 172° 15' 36'' E) in the South Pacific, where it was recovered by a PLA naval task force. A second missile (codename: 580B) was launched on 21 May at 11:19:32 local time. However, the second stage of the missile was shut down 6.4 seconds early, resulting the missile re-entry vehicle missing its targeted landing spot by 1,400km.
The last flight test of the Dongfeng 5 before its operational deployment took place on 7 December 1981, with a modified Dongfeng 5 launched from a silo at Wuzhai for a high-ballistic flight test. Two Dongfeng 5 missiles were delivered to the PLA Second Artillery Corps in 1981/82. The YF-20 rocket motor of Dongfeng 5’s first-stage was certified for design finalisation in 1983. On 1 October 1984, three Dongfeng 5 missiles were demonstrated during the National Day military parade in Beijing to celebrate the 35th anniversary of the PRC.
211 Factory and Base 062 produced a total of 16 missiles for various flight test between 1978 and 1981, with 8 missiles fired and 2 delivered to the PLA Second Artillery Corps for operational deployment. The remaining were converted into the Changzheng 2C for the FSW satellite launches. In July 1986, the nuclear warhead of the Dongfeng 5 was certified for design finalisation. On 16 December 1986, the Dongfeng 5 received its certificate for design finalisation.
Between 1987 and 1989, Base 092 produced five Dongfeng 5 missiles in the Batch-03 design for operational deployment. One of the missiles was test fired in Autumn 1989. This was also the last known Dongfeng 5 test. The remaining missiles were reportedly upgraded to the Dongfeng 5A standard in the early 1990s. The Batch 04 of eight missiles were produced by Base 062 in 1994~95, possibly in the improved Dongfeng 5A design.
Last update: 1 Nov 2010