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Taiwan’s Conventional Defence Series: Introduction
A major armed conflict across the Taiwan Strait would cause significant disruptions to the global economy and have serious geopolitical consequences. Despite persistent calls for Taiwan to enhance its asymmetrical warfare capabilities, information on Taiwan’s defence capabilities has often been outdated and incomplete. Additionally, Taiwan’s conventional deterrence is frequently overlooked in discussions of its security, particularly in the broader context of China-US relations.
This series aims to provide a clearer understanding of Taiwan’s defence capabilities and contribute to the discourse on defence and the wider geopolitical issues surrounding Taiwan. It begins by exploring Taiwan's core defence capabilities, such as air defence, sea control, counter-strike and C4ISR (Command, Control, Communications, Computers, Intelligence, Surveillance and Reconnaissance). The series will then examine the development and outlook for Taiwan’s main military branches, followed by discussions on other relevant topics, including military exercises, defence spending, recruitment, and arms development and procurement.
Long-range Air and Ballistic Missile Defence
Patriot PAC-2 and PAC-3
The previous article outlined the development and deployment of Taiwan’s[1] first domestic long-range surface-to-air missile (SAM) systems, the Tien Kung-1 and Tien Kung-2. This article continues to introduce the procurement and deployment of the Patriot PAC-2/3 system, currently serving as one of the backbones of Taiwan's long-range air and missile defence.
1. Brief procurement history
Shortly before the first fixed Tien Kung SAM site entered service in 1993, the US approved the sale of three Patriot PAC-2 GEM (Guidance Enhanced Missile) batteries to Taiwan. The first battery arrived in Taiwan in 1997.
In 2004, the defence ministry requested a roughly 4.6 billion USD budget to purchase another six batteries of PAC-3 systems and to upgrade the existing three PAC-2 batteries (to accommodate PAC-3 missiles, among other improvements[2]). After three years of debate and infighting, Taiwan’s legislation, the Legislative Yuan, incrementally approved the budget. Subsequently, the US announced three arms sales to Taiwan in 2007, 2008 and 2010 that included the upgrade of the existing three PAC-2 batteries and the sale of another six PAC-3 batteries.[3]
As an extension of the 2010 sales, the US also proposed to sell Taiwan additional PAC-3 MSE (Missile Segment Enhancement) missiles, supplementing the PAC-3 CRI (Cost Reduction Initiative) variant already purchased. While the final quantity of the PAC-3 MSE missiles agreed on between the US and Taiwan remains unconfirmed, reports indicate that the MSE variant is scheduled for delivery in 2025 and 2026. This additional sale extended the original timeframe for the entire PAC-2 upgrade and PAC-3 procurement package (2007 to 2021) to 2027. According to the Legislative Yuan, the net amount of the whole package, including the PAC-3 MSEs, amounted to approximately 5.6 billion USD.
2. Specifications
a. Missiles: PAC-2 GEM, PAC-2 CRI, PAC-3 MSE
The official ranges of the Patriot missiles are unavailable. The US National Air and Space Museum stated that the PAC-2 GEM has a range of “in excess of 60 miles (97 km).” However, the shootdown of a Russian early warning aircraft by a Patriot missile on 14 January 2024 indicates that the PAC-2’s maximum effective range might be close to 160 km when engaging air-breathing targets, as claimed by some other sources. A Taiwanese military official has also noted that the PAC-2 GEM can intercept ballistic missiles with ranges of up to 600 km range.
The PAC-3 missiles were designed primarily as a dedicated interceptor against ballistic missiles. Unlike the TVM-guided PAC-2, the PAC-3 has an active radar-homing seeker and relies on both aerodynamic control surfaces and side-thrusters for increased agility. The PAC-3 destroys in-coming ballistic missiles through direct impact. The CRI variant reportedly has an interception range of around 35 km and a maximum interception altitude of 20 km against ballistic missiles. For air-breathing targets, the interception envelope expands to a maximum range of 70 km and a maximum altitude of 24.4 km.
According to Taiwan’s defence ministry, the PAC-3 CRI missiles could:
- Enlarge engagement area of anti-ballistic missile operations;
- Increase fire power of firing units; [4]
- Significantly improve ability to destroy chemical or biological warheads; [5]
- Improve the ability to counter fast, small targets with low radar signatures, providing the potential to intercept ballistic missiles with ranges of up to 1300 km.
The PAC-3 MSE variant features a larger solid motor, among other improvements, to provide increased performance in altitude and range compared to the CRI variant (Figure 1).
Figure 1. Left: Engagement envelopes of PAC-3 CRI and MSE variants. Right: Simplified line drawings of Patriot PAC-2 GEM, PAC-3 CRI and PAC-3 MSE. Image: Lockheed Martin (Left), Milityarnyi (Right)
b. Engagement radar
According to Taiwan’s defence ministry, the three upgraded and the six newly purchased engagement radars of the Patriot batteries could, among other improvements:
● Detect targets at longer distances than older types;
● Enhance capabilities to identify targets, allowing for the distinction between an incoming warhead and booster debris;
● Improve the ability to counter fast and small targets with low radar signatures.
3. Deployment
Although the additional sale of PAC-3 MSE missiles has extended the whole upgrade and procurement package to 2027, all the six newly purchased PAC-3 batteries, including the PAC-3 CRI missiles, were reportedly delivered to Taiwan in 2017.[6] In total Taiwan purchased around 200 Patriot PAC-2 GEM missiles and over 380 PAC-3 CRI missiles.[7]
On average, each of the nine Patriot-2/3 batteries could be equipped with roughly 20 PAC-2 GEM missiles (taking into account of missiles consumed in live fire drills) and 42 PAC-3 CRI missiles (Figure 2). The setup indicates that there are basically no reloads for the PAC-2 GEM and a close to 1:1 ratio of reloads for the PAC-3 CRI per battery.[8] However, the specific ratio of PAC-2 to PAC-3 missiles can vary depending on a battery's location (Figure 3) and its primary mission. The relatively limited number of reloads will increase with the arrival of the MSE variant in the coming years. The reported number of purchases for the MSE variant ranges from 58 to around 300.[9]
Figure 2. Taiwan’s Patriot launchers are usually seen carrying either eight or 16 PAC-3 CRI missiles each. A mixed load,[10] such as two PAC-2 GEM and eight PAC-3 CRI missiles, is yet to be seen. Images: MNA (Left), Youth Daily (Right)
Figure 3. A location with the highest theoretical interception rate against ballistic missiles was chosen as a permanent base for a Patriot PAC-2/3 battery in Taichung. Image: Liberty Times
Currently, The nine Patriot batteries are deployed in northern, central, and southern parts of the main island to protect Taiwan’s densely populated west coast (Figure 4). These sites primarily support daily operations, training, and housing for personnel and equipment. The Patriot batteries also engage in regular mobile deployment exercises. In times of heightened tension, these batteries are expected to relocate to various pre-surveyed sites as part of a larger force preservation strategy, continuously changing locations while conducting air and missile defence operations (Figure 5).
Figure 4. Coverage of Patriot batteries and fixed Tien Kung sites. The Patriot’s AN/MPQ-65 radar has a 120-degree field of view, achieving 360-degree coverage by rotating the antenna. However, engagement against targets approaching from the east of the main island is limited, as the Central Mountains obstruct the radar’s line of sight. Image: Google Earth
Figure 5. Mobile deployment of Patriot ground equipment. Image: CETN
4. Live fire drills
In June 2001, Taiwan conducted a live-fire drill in which it launched three Patriot PAC-2 GEM missiles, reportedly marking the first test firing of the GEM variant outside of US territory. Since then, the PAC-2 GEM has proven to be reliable in regular live-fire drills in Taiwan. The only publicly confirmed malfunction occurred in August 2023, when one of two PAC-2 GEMs exploded shortly after launch during an annual precision munition firing drill.
During anti-ballistic missile drills, modified Tien Kung-2 SAM are often used as ballistic targets for the PAC-2 GEM variant.
Taiwan conducted its first live fire drill using the PAC-3 CRI variant in 2016 on the US soil, reportedly becoming the second foreign user after Japan to ever execute a PAC-3 missile live fire. A second live fire drill was reportedly carried out in the US in 2021. In 2023, Taiwan held a third PAC-3 live fire drill in the Republic of Palau, approximately 2100 km southeast of Taiwan, with US assistance.
Next article: In parallel with the procurement and deployment of the Patriot PAC-2/3 systems, Taiwan was also developing its own Tien Kung-3 SAM/ATBM system, with batch production beginning in 2015. The development and deployment of the Tien Kung-3 system will be discussed in the next chapter.
Tianran Xu is an Analyst for Open Nuclear Network (ONN), a programme of PAX sapiens. Tianran focuses on North East Asian security and missile systems. Tianran uses photo mensuration to measure the size, range and capacity of missiles. He also analyses photos, videos and satellite imagery to understand nuclear and missile programmes. With a background in media and journalism, Tianran is a regular contributor to Chinese and English open source and science publications. Prior to joining ONN, he worked as a journalist, editor and news assistant at both Chinese and foreign news organisations in Beijing.
Contact: txu@paxsapiens.org
[1] "China" and "Taiwan" are used to refer to the two political entities across the Taiwan Strait. The author uses "Taiwan" with the recognition that People’s Republic of China (PRC) and the Republic of China (ROC, or Taiwan) have two different official positions regarding the status of Taiwan: China views Taiwan as an inalienable part of China, while Taiwan regards itself as a sovereign and independent state.
[2] The ground equipment of the first three Patriot batteries were upgraded to the latest Configuration-3 standard, which is compatible with both PAC-2 and PAC-3 missiles.
[3] The package included one training unit, which led some reports saying that Taiwan operates a total of ten batteries. However, the training unit may not have combat functions. Additionally, nine batteries are also in line with what could be observed from satellite images.
[4] A Patriot missile launcher can carry up to 4 PAC-2, 16 PAC-3 CRI, and 12 PAC-3 MSE missiles. A launcher can also carry a mixed load of these missiles, for example, 2 PAC-2 and 8 PAC-3 CRI missiles, or 2 PAC-2 and 6 PAC-3 MSE missiles.
[5] Because the hit-to-kill method has far greater destructive power, making the spread of chemical and biological agents after an impact less likely.
[6] As can be observed on Google Earth this time is roughly consistent with the completion of six new Patriot sites.
[7] Contrary to the commonly cited number of 444 PAC-3 CRI missiles, a defence ministry document revealed in 2021 that a total of 384 PAC-3 CRI missiles will be sent back to the US in eight batches for inspections from 2023 to 2030. The number of 384 most likely excluded the two PAC-3 CRI missiles consumed in live fire drills prior to 2021.
[8] Assuming five launchers are armed with four PAC-2 GEM missiles each, and the rest three are armed with eight PAC-3 CRI missiles each.
[9] Reportedly, the fund spared from reduced purchase of PAC-3 CRI (from 444 down to 386) would be enough for 58 PAC-3 MSE rounds. The US reportedly had proposed to sell 100 PAC-3 MSEs, while a Liberty Times report claimed that the number of the MSE variant might reach 300.
[10] A Patriot missile launcher can carry up to 4 PAC-2, 16 PAC-3 CRI, and 12 PAC-3 MSE missiles. A launcher can also carry a mixed load of these missiles, for example, 2 PAC-2 and 8 PAC-3 CRI missiles, or 2 PAC-2 and 6 PAC-3 MSE missiles.
