the analyses were used to develop trajectory models for targets and missile as well as target trajectories using infrared scene generation of infrared countermeasures (IRCMs). The THAAD system is being designed, built, and integrated by Lockheed Martin Missiles and Fire Control acting as prime contractor. Key subcontractors include Raytheon, Boeing, Aerojet Rocketdyne, Honeywell, BAE Systems, Oshkosh Defense, and MiltonCAT. Demonstration and validation Engineering and manufacturing In June 2000, Lockheed won the Engineering and Manufacturing Development (EMD) contract to turn the design into a mobile tactical army fire unit. Flight tests of this system resumed with missile characterization and full system tests in 2006 at White Sands Missile Range, then moved to the Pacific Missile Range Facility. The Interceptor was led through development and initial production by Tory Bruno, who later became CEO of United Launch Alliance. THAAD-ER Lockheed is pushing for funding for the development of an extended-range (ER) version of the THAAD to counter maturing threats posed by hypersonic glide vehicles that adversaries may deploy, namely the Chinese WU-14, to penetrate the gap between low- and high-altitude missile defenses. The company performed static fire trials of a modified THAAD booster in 2006 and continued to fund the project until 2008. The current -diameter single-stage booster design would be expanded to a first stage for greater range with a second "kick stage" to close the distance to the target and provide improved velocity at burnout and more lateral movement during an engagement. Although the kill vehicle would not need redesign, the ground-based launcher would have only five missiles instead of eight. As of 2020, THAAD-ER is only an industry concept, but Lockheed believes that the Missile Defense Agency will show interest because of the weapons under development by potential adversaries. If funding for the THAAD-ER begins in 2020, a system could be produced by 2024 to provide an interim capability against a rudimentary hypersonic threat. The Pentagon is researching whether other technologies like directed energy weapons and railguns are better solutions for missile defense; these are expected to become available in the mid to late 2020s. Production Sometimes called Kinetic Kill technology, the THAAD missile destroys missiles by colliding with them, using hit-to-kill technology, like the MIM-104 Patriot PAC-3 (although the PAC-3 also contains a small explosive warhead). This is unlike the Patriot PAC-2 which carried only an explosive warhead detonated using a proximity fuze. Although the actual figures are