March 29, 2019: Saudi Arabia has made a billion dollar down payment on its $15 billion order for a THAAD (Terminal High Altitude Area Defense) anti-missile system. The down payment is to enable the manufacturer to start production on items that take a long time to produce. The Saudi order is the largest ever for THAAD. The Saudis are buying 44 launchers, 360 missiles and radar and control stations for seven batteries. In addition, this deal will pay for an upgrade of Saudi radar warning and communications infrastructure as well as bases for the THAAD batteries and maintenance facilities. The cost will cover the training of over a thousand Saudi personnel to operate and maintain the THAAD batteries and associated early warning radar systems. The Saudis will probably use contractors early on to assist with operations and maintenance. The Saudis have developed a lot of effective operators and maintenance personnel because of recent combat experience while operating its Patriot systems that have intercepted over a hundred ballistic missiles (most provided by Iran) fired from Yemen. The THAAD contract will also cover upgrades still in development or planned.

THAAD is used to defend against longer-range ballistic missiles that come at their targets at higher speeds that Patriot PAC-3 anti-missile missiles can handle. This THAAD purchase is a long-term investment. It will take five years to get most of these batteries operational. The Saudis expect the presence of THAAD to be a major deterrent to any Iranian ballistic missile attack. THAAD won’t make such an attack impossible, just more difficult. The Iranian use of ballistic missiles fired from Yemen and their inability to get past Saudi manned Patriot defenses makes the Saudi purchase of THAAD a meaningful deterrent to the Iranian missile threat to Saudi Arabia.

Each THAAD battery has 48 missiles and six launchers (an 8x8 truck carrying eight missiles in storage/launch containers) plus an AN/TPY-2 radar (on a tractor-trailer vehicle) and two truck mounted mobile tactical control stations. Two more tactical control stations are bought for spares and training as well as two spare launchers. Total cost for each battery is about a billion dollars. The 6.2 meter (18 foot long) THAAD missiles are 340mm in diameter and weigh 900 kg (1,980 pounds). This is about the same size as the Patriot anti-aircraft missile, but twice the weight of the smaller PAC-3 anti-missile version of the Patriot.

The range of THAAD is over 200 kilometers, max altitude is 150 kilometers, and top speed is 2,800 meters (9,000 feet) a second. THAAD is intended for short (like SCUD) or medium range (up to 2,000 kilometer) range ballistic missiles. THAAD has been in development since the late 1980s. Originally the U.S. Army planned to buy at least 18 launchers, 1,400 missiles, and 18 radars. That goal has been adjusted as the number of export customers increases. The Saudi order increases the number of THAAD batteries by over 50 percent.

THAAD is a step up from the Patriot PAC-3 anti-missile (which is an anti-aircraft missile adapted to take out incoming missiles). The PAC-3 works, but it has limited (35 kilometers) range. The navy has also modified its AEGIS software and Standard anti-aircraft missile system to operate like the PAC-3. This system, the RIM-161A, also known as the Standard Missile 3 (or SM-3), has a longer range than THAAD (over 500 kilometers) and max altitude of 160 kilometers. The Standard 3 is based on the Standard 2, and costs over three million dollars each. The Standard 3 has four stages. The first two stages boost the interceptor out of the atmosphere. The third stage fires twice to boost the interceptor farther beyond the earth's atmosphere. Prior to each motor firing, it takes a GPS reading to correct course for approaching the target. The fourth stage is the nine kg (20 pound) LEAP kill vehicle, which uses infrared sensors to close on the target and ram it. In addition to Patriot, Aegis and THAAD there is GBI (ground-based interceptor), a system specifically designed for intercepting ICBM warheads and only stationed in North America.

The last two tests for THAAD were in 2017 and both were successful as were the other six such tests since 2010. There have been 28 test firings of THAAD since 1995 and 22 were successful. Many of the tests before 2005 did not involve attempting to actually intercept an incoming missile warhead. Many of the tests since 2008 were to verify that new features (like the ability to hit targets closer to the surface and to share data with Patriot anti-missile systems) as well as verifying that the overall system worked. THAAD entered service in 2008 when the first THAAD anti-ballistic missile (ABM) battery was deployed. This followed a 2006 firing test that used regular army personnel and not developer technicians. In 2009 the second battery was formed. By 2012 there were five batteries and six years later that number had more than doubled.