McDonnell Douglas' (NYSE: MD) Walt Wilson, director of U.S. Air Force Delta programs, said the company is enthusiastic about its role in the success of today's mission. "We are proud to be a member of the Air Force team that made the worldwide Global Positioning System operational, and now sustains that operational capability," Wilson said.

The Delta II successfully launched all 24 original GPS satellites and three replenishment satellites before today. McDonnell Douglas will launch replenishment GPS spacecraft for the Air Force as needed through the year 2002.

The payload, a NAVSTAR GPS Block IIR satellite, is the first of a completely new GPS. Among its advantages is an ability to be launched into any of the required orbits on any day of the year with 60-day advanced scheduling. The GPS Block IIR has an estimated life span of 10 years and is equipped with advanced on-board computers to allow for in-flight software modifications.

GPS satellites form a space-based, worldwide radio navigation system with both military and commercial applications. GPS signals are accurate enough to allow velocity measurements to within a fraction of a mile per hour, location positioning to within a few feet and time calculations to within one millionth of a second.

Many uses for the GPS have developed, ranging from highly accurate mapping and geological terrain surveys to surface navigation for cars, trucks and boats.

Today's launch is the fourth consecutive successful flight of a Delta II this year since the Jan. 17 failure of a Delta II.