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

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 information —
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