Contact:

Kirsten Larson
Headquarters, Washington August 10, 2001
(Phone: 202/358-0243)

Susan Hendrix
Goddard Space Flight Center, Greenbelt, MD
(Phone: 301/286-7745)

August 10, 2001 -- RELEASE: 01-163

NASA TO ACCEPT TDRS-H COMMUNICATION SATELLITE

Boeing Satellite Systems, El Segundo, CA, has completed the verification and checkout process for the Boeing-built Tracking and Data Relay Satellite, TDRS-H, launched June 2000. NASA and Boeing are finalizing conditions for acceptance of TDRS-H, and negotiations are expected to conclude in late August.

Upon acceptance of the TDRS-H spacecraft, NASA's existing fleet will expand to seven on-orbit spacecraft. The agency will move the TDRS-H to its operational location at 171 degrees West longitude in September and rename it TDRS-8. The spacecraft then will be ready to serve the scientific community for years to come.

TDRS-H soon will be joined by TDRS-I and -J. TDRS-I is scheduled to launch Oct. 29 aboard an Atlas IIA rocket from Cape Canaveral Air Force Station, FL, at 11:14 p.m. EST, and TDRS-J will launch in October 2002. Once in place, the three next-generation satellites will double the capacity of data transmission and will provide nearly continuous, high-bandwidth communications links between Earth and space for
the International Space Station, Space Shuttle and a host of near-Earth orbiting space research missions into the next decade.

NASA's acceptance of TDRS-H has been delayed due to a performance shortfall on the Multiple-Access (MA) phased array antenna aboard the spacecraft. During on-orbit testing in August 2000, Boeing Satellite Systems, Inc., discovered that the MA communication services were performing at less-than-specified capability. All other communications services, including the newly added Ka-band single-access services, have been activated and tested and are performing well.

"Boeing has been extremely responsive since the problem was first identified," said Robert Spearing, Deputy Associate Administrator for Space Communications at NASA Headquarters. "Launching TDRS-H ahead of actual need, gave us time to identify any shortcomings and address them successfully before there was an impact on our customers."

"We are convinced that Boeing understands the most probable root cause of the underperformance and has taken the necessary actions to prevent any such shortfall from occurring on TDRS-I and -J," said TDRS Project Manager Robert Jenkens Jr. of NASA's Goddard Space Flight Center in Greenbelt, MD. Boeing has modified and tested TDRS-I and -J to ensure optimal performance.

The TDRS satellite fleet relays large volumes of data -- including voice, television and scientific nformation -- from human-rated vehicles or orbiting scientific spacecraft back to control centers on the ground. Aside from providing near-continuous coverage for human space missions, the next-generation TDRS spacecraft will relay data from the Hubble Space Telescope, Tropical Rainfall Measuring Mission, LANDSAT and the Earth Observing System. The spacecraft also provide expendable-launch-vehicle tracking services to launch service providers.