The Lockheed Martin Corp. [LMT] Global Positioning System III, or GPS III, is progressing well during its preliminary design review, the company announced.

Lockheed and its subcontractors, ITT and General Dynamics Corp. [GD], completed 19 out of 71 milestones in the review for key GPS III spacecraft subsystems and assemblies. These include L-Band transmitters, antennas, solar arrays, power regulation unit, all attitude control assemblies, as well as the Tracking Telemetry and Command (TT&C) subsystem and all TT&C assemblies. This effort will culminate in an overall GPS III Segment preliminary design review in May to ensure the preliminary design meets warfighter and civil requirements prior to advancing into the Critical Design Review phase.

The team is working under a $1.4 billion Development and Production contract awarded in May by the Global Positioning Systems Wing at the Space and Missile Systems Center at Los Angeles Air Force Base, Calif., to produce the first two GPS IIIA satellites, with first launch projected for 2014. The contract also includes options for up to 10 additional spacecraft.