The Air Force has
successfully launched its fourth Global Positioning System replenishment satellite (GPS IIR) on a Delta II rocket from Cape Canaveral Air Station, Fla. This spacecraft will join 27 other satellites in the GPS constellation.
 
"This launch is to increase global coverage and improve overal constellation health," said Col. Douglas Loverro, system program director, NAVSTAR GPS joint program office. "In such a mission, the satellite is placed into a desired plane based upon analyses, which determines which plane most likely contains a satellite or satellites which are nearing their end-of-life. This strategy allows us to fully utilize the unexpended life of satellites in all planes without risking coverage gaps if older birds should fail.
 
The Global Positioning System allows any user equipped with a GPS receiver to determine velocity and worldwide position — latitude, longitude and altitude — within a few meters. Both position data and velocity are given at a precise reference time. Although originally designed as a guidance and navigational tool for the military, GPS has proven beneficial in the fields of transportation, surveying, search and rescue operations and has created a tremendous demand in new commercial and civil markets.
 
"The GPS IIR satellites are compatible with the current system but offer improved performance," said Jerry Heydinger, program manager GPS space systems. "Increased navigation accuracy and longer autonomous satellite operation without ground control corrections will improve service for the Air Force customer and other users."
 
In recent GPS IIR news, the president’s 2001 budget request, unveiled earlier this year, builds in plans to accelerate GPS modernization. The budget, if approved by Congress, will allow GPS to provide improved capabilities sought by military and civilian users of the navigation system much sooner than previously envisioned.
 
"The new capabilities include additional military and civilian signals, increased signal power and the ability to reprogram spacecraft signals and power while on orbit," said Loverro. "These improvements will provide for better resistance to enemy jamming and improved accuracy."
 
According to Heydinger, the government will launch 16 more GPS II satellites, built by Lockheed Martin Space Systems Company, Valley Forge, Pa., over the next five years.
 
This most recent launch was the 36th success in a row for the Delta II since 1997. The Delta program office has been responsible for launching all the GPS satellites except the earlier Block I GPS satellites, which were lofted into space by refurbished Atlas ICBMs.