Sky Bow - Sky Bow I

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.
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.