DF-21

The Dong-Feng 21 (DF-21; NATO reporting name CSS-5 - Dong-Feng is a two-stage, solid-propellant, single-warhead medium-range ballistic missile (MRBM) in the Dong Feng series developed by China Changfeng Mechanics and Electronics Technology Academy. Development started in the late 1960s and was completed around 1985-86, but it was not deployed until 1991. It was developed from the submarine-launched JL-1 missile, and is China's first solid-fuel land-based missile. The U.S. Department of Defense in 2008 estimated that China had 60-80 missiles and 60 launchers.

Originally developed as a strategic weapon, the DF-21's later variants were designed for both nuclear and conventional missions. As well as a nuclear warhead of around 300 kt, it is thought that high explosive, submunition and chemical warheads are available. The latest DF-21D was said to be the world's first anti-ship ballistic missile (ASBM). The DF-21 has also been developed into a space-capable anti-satellite/anti-missile weapon carrier.

DF-21 (CSS-5 Mod-1)
The basic variant DF 21 has a maximum range of 1,700 km, and a payload of 600 kg. The missile can carry a single 500 kt nuclear warhead, with an estimated CEP of 300~400 m. This version did not enter operational service.

DF-21A (CSS-5 Mod-2)
The DF-21A was operational by 1996 and has improved accuracy with an estimated circular error probable (CEP) of 100~300m, with both GPS and a radar-based terminal guidance system in a redesigned nose. It is thought to have a lower yield, around 90 kt, but longer range (up to 2700 km).

DF-21C (CSS-5 Mod-3)
Revealed in 2006, DF-21C is believed to be a mod of DF-21. Its actual designation is unknown; it may be a version of the DF-25 missile. Its maximum range is believed to be about 1700 km. The new GPS-based guidance system has reduced the missile’s CEP to 30~40m, enabling it for precision-strike missions.

In 2010, the DF-21C was being deployed in central Western China.

DF-21D (CSS-5 Mod-4) Anti-ship ballistic missile


China has reportedly developed and tested the world's first anti-ship ballistic missile (ASBM) called DF-21D, with a maximum range of around 2700 km, in 2005, according to the US Department of Defense. It is estimated to have reached initial operating capability in 2007 or 2008. The guidance system is thought to be still in an evolutionary process as more UAV and satellites are added. The DF-21 anti-ship ballistic missile itself is assumed to have entered active service by 2009.

The US Department of Defense has stated that China has developed and reached initial operating capability of a conventionally armed high hypersonic land-based anti-ship ballistic missile based on the DF-21. This would be the world's first ASBM and the world's first weapons system capable of targeting a moving aircraft carrier strike group from long-range, land-based mobile launchers. These would combine maneuverable reentry vehicles (MaRVs) with some kind of terminal guidance system. Such a missile may have been tested in 2005-6, and the launch of the Jianbing-5/YaoGan-1 and Jianbing-6/YaoGan-2 satellites would give the Chinese targeting information from SAR (Synthetic Aperture Radar) and visual imaging respectively. The upgrades would greatly enhance China's ability to conduct sea-denial operations to prevent US carriers from intervening in the Taiwan Strait.

United States Naval Institute in 2009 stated that such a warhead would be large enough to destroy an aircraft carrier in one hit and that there was "currently ... no defense against it" if it worked as theorized.

The United States Navy has responded by switching its focus from a close blockade force of shallow water vessels to return to building deep water ballistic defense destroyers. The United States has also assigned most of its ballistic missile defense capable ships to the Pacific, extended the BMD program to all Aegis destroyers and increased procurement of SM-3 BMD missiles. The United States also has a large network optimized for tracking ballistic missile launches which may give carrier groups sufficient warning in order to move away from the target area while the missile is in flight.

Use of such missile has been said by some experts to potentially lead to nuclear exchange, regional arms races with India and Japan, and the end of the INF Treaty between the United States and the Soviet Union, to which the People's Republic of China is not a party.

Some have also suggested China could develop a "MIRVd" DF-21D with multiple independent missiles.

China has recently launched a series of satellites to support its ASBM efforts: China is reported to be working on an Over-the-horizon radar to locate the targets for the ASBM.
 * Yaogan-VII electro-optical satellite - 9 December 2009
 * Yaogan-VIII synthetic aperture radar satellite - 14 December 2009
 * Yaogan-IX Naval Ocean Surveillance System (NOSS) constellation (3 satellites in formation) - 5 March 2010.
 * Yaogan-XVI Naval Ocean Surveillance System (NOSS) constellation - 25 November 2012

An apparent test of the missile has been made against a target in the Gobi desert.

KT ASAT
KT series anti satellite missiles / anti ballistic missiles is reportedly a series of highly classified and thus little known missiles based on DF-21. Designed to intercept satellites and ballistic missiles, KT series utilizes experience gained from earlier FJ ABM developed decades earlier. Four models of KT series have been developed so far, including KT-1, KT-2, KT-2A and KT-III: It is rumored that there are other versions of KT under development, but these claims have yet to be verified.
 * KT-1: designed to engage sub-orbital targets.
 * KT-1A: upgraded KT-1
 * KT-409: upgraded solid-fuelled variant
 * SC-19: KT-1 variant
 * KT-2: designed to engage low earth orbit (LEO) targets at altitude up to 600 km.
 * KT-2A: designed to engage polar orbital targets.
 * KT-III: designed to engage targets at altitude 1000 km or higher.