SOSTAR-X (Stand-Off Surveillance and Target Acquisition Radar Demonstrator) entered the final phase of mission system integration, as of June 2, after three years of intensive design and development. This step forward came in stride with the successful tests of the active array antenna panels. SOSTAR-X will demonstrate the scalable active electronically scanned array (AESA) as part of an advanced ground surveillance radar by 2007. It must, at that time, meet the majority of NATO AGS staff requirements. The sensor will be capable of collecting MTI data, tracking targets and delivering spot SAR images from distances beyond 95 miles. SOSTAR GmbH is a joint venture between Dutch Space, EADS, Galileo Avionica, Indra Sistemas and Thales. The program is being funded through an R&D contract under a government MOU between France, Germany, Italy, Spain and the Netherlands. In April, SOSTAR-X reached a milestone when the first prime items Core Electronics and Operations & Control passed the acceptance test at the EADS facilities in Friedrichshafen, Germany. After completing ground tests planned for this autumn, the system will be integrated on a Fokker 100 test bed aircraft. Company and customer flight demonstrations will be conducted on a Fokker 100 as well.