"The Global Positioning System -- GPS -- Block IIR and IIR-M satellite constellation, designed and built by Lockheed Martin to provide significantly improved navigation capabilities for military and civilian users worldwide, has accumulated over 75 years of successful on-orbit operations," the company said in a statement last week.
"GPS provides essential services including situational awareness and precision weapon guidance for the military. It is also an information resource supporting a wide range of civil, scientific and commercial functions -- from air traffic control to the Internet -- with precision location and timing information," Lockheed Martin said.
Lockheed Martin said its Space Systems operation in Valley Forge, Pa. was "the prime contractor for the GPS IIR program. The company designed and built 21 IIR spacecraft for the Global Positioning Systems Wing, Space and Missile Systems Center, Los Angeles Air Force Base, Calif."
"The final eight spacecraft, designated Block IIR-M, were modernized to enhance operations and navigation signal performance for military and civilian GPS users around the globe. ITT, Clifton, N.J. supplied all 21 navigation payloads for both the IIR and IIR-M spacecraft," the company said.
"GPS IIR satellites have been delivering improved navigation capabilities to the U.S. military and civil users since the first successful launch of a IIR satellite on July 23, 1997. There are currently 12 operational Block IIR and five IIR-M satellites within the overall 30-spacecraft constellation. The team is now gearing up for the launch of the sixth IIR-M satellite scheduled for liftoff in March from Cape Canaveral," the company said.
"We are proud of this milestone and our partnership with the Air Force in providing reliable, high-performance GPS spacecraft that not only help our war fighters achieve their missions with greater speed and effectiveness, but also serve millions of civil users around the globe," said Don DeGryse, Lockheed Martin's vice president of navigation systems. "We look forward to achieving mission success and delivering even greater navigation capabilities as we prepare to launch the next modernized satellite."