KING OF PRUSSIA, Pa. -- Lockheed Martin announced the delivery of the eighth and final satellite in the modernized Global Positioning System Block IIR (GPS IIR-M) production program to the Air Force.

The GPS constellation provides critical situational awareness and precision weapon guidance for the military. The worldwide system also supports a wide range of civil, scientific and commercial functions ­ from air traffic control to the Internet ­ with precision location and timing information.

There are currently three IIR-M spacecraft on-orbit, along with 12 original Block IIR satellites within the overall 30-spacecraft GPS constellation. Each satellite in the Block IIR-M series includes a modernized antenna panel that provides increased signal power to receivers on the ground; two new military signals for improved accuracy, enhanced encryption and anti-jamming capabilities for the military; and a second civil signal that will provide users with an open access signal on a different frequency.

Based on the navigation user range error, which measures GPS accuracy, the Block IIR satellites enable properly equipped users to determine precise time and velocity and worldwide latitude, longitude and altitude to within one meter.

Over 250 employees from Lockheed Martin, navigation payload provider ITT of Clifton, N.J., and representatives from the U.S. Air Force and other government agencies, gathered at Lockheed Martin's facilities in Valley Forge, Pa., to celebrate the achievement and the overall success of the GPS IIR program.

"This historic milestone is the result of our team's commitment to superior program execution and dedication to achieving mission success for our customer," said Don DeGryse, Lockheed Martin's vice president of Navigation Systems. "We take great pride in the outstanding on-orbit performance of these advanced spacecraft and look forward to further enhancing the worldwide constellation with the launch of the remaining IIR-M spacecraft."

Lockheed Martin Space Systems, Denver, Colo., is 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. The company is also responsible for launch and flight operations support of the GPS IIR and IIR-M satellites.

The third GPS IIR-M spacecraft was launched successfully on Nov. 17, 2006 and was declared operational on Dec. 12 by Air Force Space Command's 2nd Space Operations Squadron (2 SOPS) at Schriever Air Force Base, Colo., which manages and operates the GPS constellation for both civil and military users.

The fourth GPS Block IIR-M satellite has been delivered to Cape Canaveral to support a late 2007 launch. Remaining satellites delivered to storage are available for launch when requested by the Air Force for constellation sustainment.

The company is leveraging its proven record of building advanced global positioning system satellites for the next-generation system, known as GPS III. The Lockheed-led GPS III Space Segment team, which includes ITT and General Dynamics, is currently working under a Phase A Concept Development contract, with the Air Force expected to award a multi-billion dollar development contract to a single contractor in late 2007.

Headquartered in Bethesda, Md., Lockheed Martin employs about 140,000 people worldwide and is principally engaged in the research, design, development, manufacture, integration and sustainment of advanced technology systems, products and services. The corporation reported 2006 sales of $39.6 billion.