The newest modernized GPS Block 2R satellite has been declared fully operational by the U.S. Air Force, manufacturer Lockheed Martin announced Dec. 19. Launched in November, GPS 2R-16M joins two other modernized Block 2R-M spacecraft on orbit. Lockheed Martin is producing eight Block 2R-M satellites, and the fourth spacecraft in the series has been delivered for a 2007 launch if needed, the company said.