It was built by Lockheed Martin, using the AS-4000 satellite bus, and had a mass of 2,032 kilograms (4,480 lb).[2] USA-203 was launched at 08:34 UTC on 24 March 2009, atop a Delta II carrier rocket, flight number D340, flying in the 7925-9.5 configuration.The satellite raised itself into medium Earth orbit using a Star-37FM apogee motor.[4] It was intended to operate in slot 2 of plane B of the GPS constellation, replacing USA-128,[6] and to broadcast signal PRN-01.[7] During on-orbit testing an anomaly was discovered with the signals it was broadcasting, which prevented its operational use.