Status Report

NASA Expendable Launch Vehicle Status Report 9 February 2005

By SpaceRef Editor
February 9, 2005
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MISSION: Demonstration of Autonomous Rendezvous Technology (DART)

LAUNCH VEHICLE: Pegasus XL (Orbital Sciences Corporation)



In the Orbital Sciences Corporation hangar at Vandenberg Air Force
Base in California, work continues to prepare the Pegasus XL for the
launch of the DART spacecraft. The gaseous nitrogen regulator has
been repaired and the Reaction Control System is now being returned
to Vandenberg for reinstallation on the Pegasus next week. Once that
is complete, the DART spacecraft can be re-mated to the launch

A preliminary review has been performed on the loads imparted by the
Pegasus launch vehicle on the DART spacecraft. There has also been
additional testing to ensure that the flight hardware on DART can
withstand the change in vehicle loads. The final loads analysis is
scheduled to be complete late this month.

DART was designed and built for NASA by Orbital Sciences Corporation
as an advanced flight demonstrator to locate and maneuver near an
orbiting satellite. The DART spacecraft weighs about 800 pounds, and
is 6 feet long and 3 feet in diameter. The Orbital Sciences Pegasus
XL vehicle will launch DART into a circular polar orbit of 475 miles.
DART project management is the responsibility of NASA’s Marshall
Space Flight Center in Huntsville, Ala., and the NASA launch
management is the responsibility of the Kennedy Space Center Launch
Services Program.

MISSION: NOAA-N (National Oceanic & Atmospheric Administration)

LAUNCH VEHICLE: Boeing Delta II 7320

LAUNCH PAD: SLC-2, Vandenberg Air Force Base, Calif.



During testing of NOAA-N at Vandenberg Air Force Base in California,
an out-of-specification frequency change was detected to have
occurred in one of the spacecraft’s four S-Band transmitters. The
drift of the center frequency means that tracking stations on the
ground would have difficulty locking on to the signal. When last
measured in December 2004, the frequency was nominal. Failure
analysis must be performed to determine why the center frequency has
drifted, which will lead to a determination being made on whether the
transmitter needs to be removed and replaced, and whether there
should be concern for the other transmitters. These units are not
easily accessible. A launch postponement is necessary, though at this
time the length of the delay is not known.

At Space Launch Complex 2, preparations for launch of the Boeing Delta
II are going well. The First Stage Liquid Oxygen “LOX” Leak Check
originally scheduled for this week is being rescheduled as a result
of the launch postponement.

The first power-on testing of the Boeing Delta II launch vehicle began
on Jan. 31. The Vehicle Guidance and Control Qualifications, which
are tests of the Delta II guidance and control systems, occurred Feb.
4. The build-up of the Boeing Delta II at the pad began on Jan. 12
with the erection of the first stage and interstage adapter. The
three strap-on solid rocket boosters were attached to the vehicle on
Jan. 17. The second stage was hoisted atop the first stage on Jan.

After launch, NOAA-N will be renamed NOAA-18 and will provide
measurements of the Earth’s surface and atmosphere that will be
entered into NOAA’s weather forecasting models and used for other
environmental studies. Each day, the satellite will send data to
NOAA’s Command and Data Acquisition station computers, adding vital
information to forecasting models, especially over the oceans, where
conventional data is lacking.

The spacecraft will be turned over from NASA to NOAA after on-orbit
checkout is complete. NASA’s Goddard Space Flight Center in Maryland
is responsible for NOAA-N project management. The spacecraft was
built for NASA by Lockheed Martin Space Systems Company. The Delta II
launch service is provided by the Boeing Expendable Launch Systems
Company. Launch management is the responsibility of the NASA Kennedy
Space Center Launch Services Program office.

SpaceRef staff editor.