WEEKLY HIGHLIGHTS FOR WEEK ENDING 21 NOVEMBER 2003:
GRAVITY PROBE B LAUNCH DELAYED
Last weekend, a very difficult decision was made jointly by NASA, Stanford, and Lockheed Martin to delay the Gravity Probe B launch in order to eliminate a grounding problem in a voltage converter that resides in the Experiment Control Unit (ECU) on board the Gravity Probe B spacecraft. The ECU will be removed from the spacecraft, the faulty converter will be replaced, and the ECU will then be tested and reinstalled. This repair will ensure full redundancy in the ECU and maximize the reliability of the spacecraft on launch. We are in the process of creating a repair plan, from which we will set a new launch date. Please bookmark this Web site and check back any time to get the latest information on the status of the Gravity Probe B launch and mission.
VANDENBERG AIR FORCE BASE OPERATIONS THIS WEEKThe following activities were completed at VAFB this past week:
- The Gravity Probe B space vehicle, which was ready to move to the launch pad, was de-coupled from the Delta II payload attachment fitting (PAF) and returned to its test stand in the clean room preparation facility. It will remain in this facility at Vandenberg throughout the repair period, until it is once again made ready to move to the launch pad.
- Preparations are now underway to remove two of the four solar panels before Thanksgiving so that the dewar can be serviced during the repair period.
- Operations supporting the removal of the ECU unit containing the faulty voltage converter have begun.
- The Delta II launch vehicle, with the solid motors attached, will remain on the launch pad, surrounded by the mobile service tower (MST), for the duration of the repair period. Small maintenance items have been identified and will be accomplished to accommodate the Delta II launch delay.
VIDEO CLIP FROM THE SPACE VEHICLE PREPARATION ROOM AT VANDENBERG
Photo: The Gravity Probe B spacecraft, sitting in the preparation clean room at Vandenberg AFB, with its cylindrical payload attachment fitting (PAF) installed at its base. The spacecraft has now been de-coupled from the PAF, in preparation for removing the ECU.