DF-31 (CSS-9) Intercontinental Ballistic Missile
Last updated: 31 March 2008
The DF-31 (DongFeng-31, NATO reporting name: CSS-9), designed and developed by 4th Space Academy (now Academy of Rocket Motor Technology, ARMT), is a three-stage, road-mobile, solid-propellant ICBM capable of delivering a single 1,000kT nuclear warhead. The missile incorporates many advanced technologies similar to current generation Russian missiles, including the transporter-erector-launcher (TEL) for upgraded mobility, use of penetration aids such as decoys or chaffs, and an improved solid propellant.
Originally intended to hit the European theatre of the Soviet Union, the 8,000km-range DF-31 was developed in parallel with the 12,000km-range DF-41 ICBM designed to hit the targets in the United States. As the DF-41 programme was finally abandoned in 2002 due to the PRC’s revised nuclear strategy, the DF-31 became China’s sole active ICBM programme. However, the DF-31 is thought to be inadequate to provide an effective nuclear deterrent for China due to its limited range. For example, when launched from central China, the DF-31 can only reach a smaller corner of the west coast of the United States. This limitation has driven China to pursue an improved version known as DF-31A with extended range and enhanced capabilities.
The PRC is currently developing two follow-on versions of the DF-31: the 11,000km-range DF-31A ICBM with improved accuracy and possibly multiple independently-targeted re-entry vehicle (MIRV) capability, and the JL-2 submarine-launched ballistic missile (SLBM) that will be deployed on China’s next-generation Type 094 nuclear missile submarines (SSBN).
The DF-31 offers a number of operational advantages over older Chinese missiles such as the DF-4. Instead of being launched from a fixed location, the DF-31 can be transported on its transporter-erector-launcher (TEL) vehicle to one of many predetermined launch sites, providing greater survivability in the event of a first strike. Furthermore, the use of solid propellant gives the missile a longer service-life and shorter launch time compared to the liquid fuel ICBMs. The DF-31 may also be the first Chinese missile to be armed with a lightweight warhead allegedly copied from the U.S. W-88 or W-70 warhead designs, though so far no sound evidence has been found to support this claim.
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DF-31 ICBM system (Chinese Internet) |
History
The DF-31 programme began in 1986 as a successor to the DF-4 (CSS-3) liquid-propellant long-range ballistic missile. The solid-propellant rocket engine (FG-6?) for the first- and second-stage of the DF-31 was successfully tested in late 1983. The rocket engine for the third-stage was tested in mid-1984. The DF-31 entered the engineering development in 1987. The first test launch of the missile using a dummy warhead was conducted on 2 August 1999, from the Wuzhai Missile Test facilities in Shanxi Province to the impact zone in Lop Nor in Xinjiang. Two subsequent test launches were carried out in late 2000. However, some suggested that the three flight tests all failed and the first successful flight test was only carried out on 4 September 2006.
During the 1999 National Day parade to celebrate the 50th anniversary of the PRC, the DF-31 ICBM system was briefly displayed in front to world press cameras for the first time, though the missile itself could not be seen as it was concealed in the large canister carried on a truck-trailer TEL vehicle. Despite this public display, operational deployment of the missile has not come as quickly as previously predicted. Some reports suggested that the missile development was only partially successful due to various technological challenges and design flaws. The 2007 U.S. Department of Defense (DOD) report to congress on the PRC military power suggested that the DF-31 has reached “initial threat availability (ITA) in 2006” and possible “operational status by May 2007”. The 2008 version of the report confirmed that less than 10 missiles/launchers are now being deployed by units within the PLA Second Artillery Corps.
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| This 2008 image from the China Central Television shows an operational DF-31 launch unit in the PLA Second Artillery Corps (CCTV) |
Missile
It was estimated that the DF-31 has a payload of about 700kg (other source suggested between 1,050 and 1,750kg), which can be equipped with a single 1,000kT yield nuclear warhead. The missile has a launch weight of 42,000kg, with a length of 13.0m and a body diameter of 2.25m. Carried inside a large canister launcher mounted on the TEL vehicle, the DF-31 uses an inertial guidance system that is equipped with a stellar update system, and is expected to have an accuracy of at least 300m CEP. Some resource suggested that the silo and TEL-based version have 100 and 150m CEP respectively.
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DF-31 missile model and DF-31 launch
(Chinese Internet) |
Transporter-Erector-Launcher (TEL) Vehicle
The DF-31 can be launched from missile silos or TEL vehicles. Early TEL-version of the DF-31 was carried on a Hanyang HY473 16-wheeled truck consisting of a tractor and a semi-trailer, while the DF-31s displayed in the 1999 National Day parade were carried on the improved Hanyang HY4301 TEL. These TEL vehicles provide the missile with limited road mobile capability, but offer no off-road travelling capability. A new single 12- or 16-wheeled TEL similar to those used by the Russian ICBM systems is reportedly in development. There has been speculation that China was also developing a railway-based TEL for the DF-31 but this cannot be confirmed.
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DF-31 TEL vehicle in the firing position
(Chinese Internet) |
DF-31A
As the DF-31 did not fully meet the PLA requirements, ARMT has been developing an enhanced variant known as DF-31A with extended range and better accuracy since the early 2000s. Few details are known about the new system. The missile is likely to be a replacement for the now-cancelled DF-41 ICBM as the future mainstay of China’s intercontinental ballistic missile (ICBM) arsenal. Like the DF-31, the DF-31A is also road-mobile and uses solid-propellant.
The upgraded DF-31A is said to have a range of 10,000~11,000km, enabling it to cover most targets in the United States. The missile is said to be capable of deliver 3~5 multiple independently-targeted re-entry vehicles (MIRVs), each with 20, 90 or 150kT yield. It is also possibly equipped with penetration aids such as decoys and flares to complicate enemy missile warning and defence.
Foreign intelligence has noted a Belarus MAZ7916 12-wheel mobile missile TEL at the DF-31 production facility in Nanyuan, Beijing in the 1990s. Used for former Soviet SS-20 IRBM, the MAZ7916 TEL has a significantly better cross-country travelling capability than the existing Hanyang TEL truck used by the DF-31. China may have incorporated some MAZ technologies including all-wheel independent suspension, higher ground clearance, driver-controlled central tire-inflation systems, and large tires on its own indigenous heavy-duty cross-country vehicles to develop a fully off-road mobile TEL for the DF-31A.
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DF-31A TEL? (Chinese Internet) |
Specifications
Configuration: Three-stage
Length: 13m
Diameter: 2.25m
Launch weight: 42,000kg
Propellant: Solid fuel
Guidance: Inertial + stellar update
Range: 7,200~8,000km (DF-31); 11,200 (DF-31A)
Deployment: Silo or road mobile
Re-entry vehicle mass: 700kg (1,050~1,750kg)
Warhead: One single 1,000kT
Accuracy: 100~300m CEP
Launch preparation time: 15~30 min
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