Sky Bow The Sky Bow series of surface - to - air missile s were developed by the Republic of China ( Taiwan ) and are currently in used for air defense purposes . Development . The development of the Sky Bow 1 ( Tien Kung 1 ) missile system was started in 1981 by the Chungshan Institute of Science and Technology ( CSIST ) . Firing trials started in 1986 , using a semi - active radar seeker . A passive IR terminal seeker was also developed as a secondary seeker for the TK - 1 , this was successfully tested against a HAWK missile target but never put in the production missile . CSIST also developed a large multifunction , phased - array radar known as Chang Bai ( long white ) for use with the Tien Kung ( Sky Bow ) series surface - to - air missile systems with 120 degree coverage and a maximum range of 450 km . Two versions of the phased array radar exist , a towed trailer radar and fixed " hardened " radar sites . The Chang Bai radar system is reported to be based on the Lockheed Martin ' s ADAR - HP ( Air Defense Array Radar - High Power ) design and operates in the 2 – 4 GHz range ( S - band ) . At least seven systems are said to be currently in service . The system performance specifications remain classified , but its reported effective detection range against 1m2 target to be around 400 km . There was also a mobile version of the phased array radar developed in the late 1990s which could provide all - round radar cover with four separate faces but with a much decreased detection range . This version only appeared in public once but was never put into service . The development of Sky Bow 2 started around 1986 , this added a tandem boost motor and an active radar terminal seeker . Proposals were reported to develop Sky Bow 2 into a surface - to - surface missile ; unconfirmed reports suggest that this missile is known as Tien Chi . Modifications have been developed for Sky Bow 2 , changing it into a single stage rocket and to provide it with a limited capability against shorter - range ballistic missiles ; the first test firing against a ballistic missile target was reported in September 2008 . Seven batteries of TK - 1 / 2 SAMs are in service and deployed throughout Taiwan , on the Pescadores , and Dong Ying island . Sky Bow I . The Sky Bow I ( TK - 1 ) ( 天弓一 , Tien Kung I ) is a surface - to - air missile ( SAM ) system developed by the Chungshan Institute of Science and Technology ( CSIST ) in Taiwan , ROC . Originally based on the aerodynamics of the MIM - 72 HAWK missile , the original missile design resembled a scaled - up Raytheon AIM - 54 Phoenix . The TK - 1 missile was subsequently redesigned and eventually became very similar in appearance to the US Patriot missile after the US government allowed Raytheon to transfer 85 percent of the MIM - 104 Patriot missile technology . There is no track - via - missile ( TVM ) homing capability as this technology was not included in the technology package licensed to Taiwan ; the TK - 1 system operates in a similar manner to the US Standard SM2 missile , requiring an illuminating radar during the terminal phase . The TK - 1 is designed primarily to target low and medium altitude attacks . Each TK - 1 battery has one Change Bai S - Band phased - array radar for search and target tracking and two CS / MPG - 25 target illuminator radars that operates in the X - Band ( 18 – 32 GHz ) range for the terminal phase , servicing three or four 4 - round missile launchers . The combination of inertial / autopilot and mid - course command guidance with a terminal semi - active radar seeker allows the TK - 1 missile to fly an energy - efficient flight path to the vicinity of the target where the seeker ' s semi - active radar would then receive target illumination for the final seconds of the engagement , giving the target minimum amount of time either to evade or commence electronic countermeasure ( ECM ) . The CS / MPG - 25 is a continuous wave disk antenna illuminator radar with a 200 km range that is solely developed by CSIST , and was derived from the I - HAWK AN / MPQ - 46 High - Power Illuminator ( HPI ) radar but is estimated to be 60 percent more powerful in output with improved EW , ECM , and IFF capabilities . It is tied into the main phased - array radar on a time - share basis similar to that employ by the US Navy ' s AEGIS air defence system , allowing the TK - 1 surface - to - air missile system multiple target engagement capability . Two versions of the missile launcher exist , one is housed in underground shelters designed to survive an intensive attack . < br > The other is a towed mobile version , and is an integral part of Taiwan ' s dense air defense network . In addition to bases on Taiwan proper , the TK - 1 has also been deployed by the ROC Army on the outlying islands of Penghu and Dong Ying , bringing all of the Taiwan Strait and parts of the PRC ' s Fujian , Zhejiang and Guangdong Provinces within range . It was reported in Jane ' s Missiles and Rockets , August 2006 ' s issue , that the Tien Kung 1 surface - to - air missile ( SAM ) system would be retired . The TK - 1 missiles would be replaced with TK - 2 missile rounds and the existing TK - 1 system would be upgraded with radar and training simulator to the Tien Kung II standard . Sky Bow II . The Sky Bow II ( TK - 2 ) ( 天弓二 , Tien Kung II ) is a SAM system also developed by the Chungshan Institute of Science and Technology . Originally a TK - 1 with a first - stage booster , the system became a slightly - enlarged modified version of the Sky Bow I ( TK - 1 ) missile using an X - Band active - radar seeker , with a longer range and limited anti - missile capability . The TK - 2 active radar seeker operates in the 28 – 32 GHz frequency range and provides reasonably good performance against air - breathing targets of typical aircraft size . The X - Band active radar seeker used on the TK - 2 SAM system was developed from licensed radar technology that CSIST purchased from the U . S . in the 1980s . The TK - 2 also have the added benefit of being able to use the same box launcher as the TK - 1 . Internal components were replaced with miniaturized parts to take advantage of modern electronics technologies , yielding extra room within the missile for more fuel and a more powerful main rocket motor . It is speculated that the earlier TK - 2 design has been developed into a surface - to - surface missile . The TK - 2 has also been modified for use as a sounding rocket to perform upper atmospheric research for the civilian space program . The sounding rocket test vehicle launched on December 24 , 2003 , measures 7 . 7m in overall length and 1 , 680 kg in launch weight . It reached a maximum altitude of almost 270 km and splashed 142 km down range around 8 minutes after launch into the Pacific . The science mission payload was in the weight class and the rocket reached a burnout velocity of 2 , 000 m / s . According to the report from Taiwan Defense Review , depending on its payload and launch parameters , the rocket can be converted to attain a horizontal maximum range of up to 500 km . Sky Bow III . The Sky Bow III ( TK - 3 ) ( 天弓三 , Tien Kung III ) is the third generation version of the Tien Kung family of surface - to - Air missile ( SAM ) systems developed by the Chungshan Institute of Science and Technology ( CSIST ) in Taiwan . It was reported that Taiwan had initially sought and even proposed a joint development effort to co - produced a missile defense interceptor with the U . S . , Taiwan officials asked for U . S . technical support for Taiwan ' s indigenous anti - tactical ballistic missile ( ATBM ) effort , including the transfer of Hit - to - Kill ( HTK ) technologies , specifically those related to an active radar Ka - band seeker and precision attitude control . CSIST was reported to had sought the release of the associated traveling - wave tube ( TWT ) transmitter of the Ka - band active radar seeker technology . However , U . S . refusal of the export release of a complete Ka - band active radar seeker without tamper protection or to provide the TWT on a stand - alone basis , forced CSIST to use a different ( see below for related discussion ) active radar seeker technology with significant European content . The TK - 3 ( formerly known as TK - 2 ATBM ) is a lower - tier missile defense system based on the TK - 2 missile that uses an imported Ku - Band ( 12 – 18 GHz ) active radar seeker , a directed fragmentation warhead , and improved precision controls for engaging high - speed , low radar cross - section ( RCS ) targets such as tactical ballistic missiles . It is designed with greater mobility in mind than the original TK - 1 / 2 systems , with an integrated battle management system , and uses an upgraded Chang Bai phased array radar or with the new mobile phased - array radar that is reportedly called the Mobile 3 - Dimensional ( 3D ) Air Defense Fire Control Phased Array Radar ( Mobile 3D ADFCPAR ) . The upgraded Chang Bai phased array radar is reportedly called the Chang Shan ( " Long Mountain " ) radar system , it will reportedly increase the radar ' s radiated power over the Change Bai system by 170 % , employs four times the number of phase shifter elements vis - a - vis the Chang Bai radar system , with substantial improvement in tracking ability to include tactical ballistic missile warhead sized targets , and with a reported range of 1 , 000 km . The new mobile radar bears a striking physical resemblance to the Patriot ' s Raytheon AN / MPQ - 53 radar system . It is reported to operate on the C - Band ( 4 – 8 GHz ) frequency range , and like the AN / MPQ - 53 system , it is trailer - mounted with a rectangular planar array radar of approximately similar size . However , it does not appear to have any identifiable missile guidance sub - array like those found below the main array on the AN / MPQ - 53 system and it is therefore not clear if this new radar can provide target guidance illumination function in support of TK - 1 SARH missiles . However , this should not present any problem for the new radar to be utilized on both TK - 2 missile ( X - Band ) and TK - 3 missile ( Ku - Band ) active radar seekers , as these missile systems does not require target illumination . The new radar enhances the survivability and operational flexibility of the TK2 / 3 missile systems by allowing a TK surface - air - missile battery to be deployed rapidly to a previously unprepared site . Unlike the TK - 1 / 2 systems , TK - 3 missile system uses vertical launch cells drawn by a transporter - erector - launcher and the TK - 3 is reported to have a maximum range of better than 200 km . It was officially revealed on the October 10 , 2007 , military parade . By summer in 2013 , it enters mass production and becomes a part of Taiwan ' s Anti - Tactical Ballistic Missile ( ATBM ) project , Taiwan ' s planned missile shield . The R . O . C . ( Taiwan ) develops the Sky Bow III missiles to engage stealth aircrafts such as J - 20 / 31 with the AN / MPQ - 53 system of PESA radar .