USA-203, also known as GPS IIR-20(M), GPS IIRM-7 and GPS SVN-49, is an American

navigation satellite A satellite navigation or satnav system is a system that uses satellites to provide autonomous geopositioning. A satellite navigation system with global coverage is termed global navigation satellite system (GNSS). , four global systems are op ...

which was intended to become part of the

Global Positioning System The Global Positioning System (GPS) is a satellite-based hyperbolic navigation system owned by the United States Space Force and operated by Mission Delta 31. It is one of the global navigation satellite systems (GNSS) that provide ge ...

. It was the sixth of seven Block IIRM satellites to be launched, and the twentieth of twenty one Block IIR satellites overall. It was built by

Lockheed Martin The Lockheed Martin Corporation is an American Arms industry, defense and aerospace manufacturer with worldwide interests. It was formed by the merger of Lockheed Corporation with Martin Marietta on March 15, 1995. It is headquartered in North ...

, using the AS-4000

satellite bus A satellite bus (or spacecraft bus) is the main body and structural component of a satellite or spacecraft, in which the payload and all scientific instruments are held. Bus-derived satellites are less customized than specially-produced satelli ...

, and had a mass of . USA-203 was launched at 08:34 UTC on 24 March 2009, atop a

Delta II Delta II was an expendable launch system, originally designed and built by McDonnell Douglas, and sometimes known as the Thorad Delta 1. Delta II was part of the Delta rocket family, derived directly from the Delta 3000, and entered service in ...

carrier rocket, flight number D340, flying in the 7925-9.5 configuration. The launch took place from Space Launch Complex 17A at the

Cape Canaveral Air Force Station Cape Canaveral Space Force Station (CCSFS) is an installation of the United States Space Force's Space Launch Delta 45, located on Cape Canaveral in Brevard County, Florida. Headquartered at the nearby Patrick Space Force Base, the sta ...

, and placed USA-203 into a transfer orbit. The satellite raised itself into

medium Earth orbit A medium Earth orbit (MEO) is an geocentric orbit, Earth-centered orbit with an altitude above a low Earth orbit (LEO) and below a high Earth orbit (HEO) – between above sea level.

using a Star-37FM apogee motor. USA-203 is located in an orbit with a

perigee An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. The line of apsides (also called apse line, or major axis of the orbit) is the line connecting the two extreme values. Apsides perta ...

of , an

apogee An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. The line of apsides (also called apse line, or major axis of the orbit) is the line connecting the two extreme values. Apsides perta ...

of , a period of 718 minutes, and 55.8 degrees of

inclination Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a reference plane and the orbital plane or axis of direction of the orbiting object. For a satellite orbiting the Eart ...

to the equator. It was intended to operate in slot 2 of plane B of the GPS constellation, replacing USA-128, and to broadcast signal PRN-01. During on-orbit testing an anomaly was discovered with the signals it was broadcasting, which prevented its operational use. It was decommissioned on 6 May 2011, two years into its ten-year design life. In addition to its operational navigation signals, USA-203 was also equipped to broadcast a demonstration of the L5 signal which would be introduced with the GPS Block IIF series. The satellite was able to broadcast this signal correctly, but it was discovered that a filter used to produce the L5 signal was causing the disruption to its other frequencies. USA-203

References

{{Orbital launches in 2009 Spacecraft launched in 2009 GPS satellites USA satellites