total of 5 GEOs. A complement of satellites in low Earth orbit (LEO) was planned as part of the program (SBIRS-Low), but this has been moved into the Space Tracking and Surveillance System (STSS) program. SBIRS continues to struggle with cost overruns, with Nunn-McCurdy breaches occurring in 2001 and 2005. By September 2007, the expected project cost had increased to US$10.4 billion. In December 2005, following the third SBIRS Nunn-McCurdy violation, the government decided to compete SBIRS GEO-4 and SBIRS GEO-5, with an option to buy the SBIRS GEO-3 contingent based on the performance of the first two. On 2 June 2009, Lockheed Martin announced it had been awarded a contract for the third SBIRS HEO payload and the third SBIRS GEO satellite, and for associated ground equipment modifications. On 10 July 2009, Lockheed Martin was awarded US$262.5 million as down payment by the USAF towards the purchase of a fourth satellite. The first SBIRS GEO satellite of the SBIRS program, SBIRS GEO-1, was successfully launched from Cape Canaveral on an Atlas V launch vehicle on 7 May 2011. In June 2014, Lockheed Martin was contracted by the USAF to build SBIRS GEO-5 and SBIRS GEO-6, at a cost of US$1.86 billion. The FY 2021 budget allocates US$2.5 billion to SBIRS for the United States Space Force. SBIRS High SBIRS High (also now simply referred to as "SBIRS") is to consist of four dedicated satellites operating in geosynchronous Earth orbit, and sensors on two host satellites operating in a highly elliptical orbit. SBIRS High will replace the Defense Support Program (DSP) satellites and is intended primarily to provide enhanced strategic and theater ballistic missile warning capabilities. SBIRS High GEO 1 was launched on 7 May 2011. Two SBIRS sensors hosted on two classified satellites in highly elliptical orbit have already been launched, probably as part of the NROL-22 (USA 184) and NROL-28 (USA 200) launches in 2006 and 2008. USA 184 and USA 200 are believed by analysts to be ELINT satellites in the family of JUMPSEAT and TRUMPET; TRUMPET has been reported to have carried an infrared sensor called HERITAGE. The prime contractor for SBIRS is Lockheed Martin, with Northrop Grumman as the major subcontractor. Lockheed Martin also provides the satellite for SBIRS GEO. The system's expected deployment was delayed from December 2009 to 2011 because of problems with Lockheed's workmanship on system components, including unresolved software malfunctions and