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Control system tests begin for Vega's main engine EUROPEAN SPACE AGENCY NEWS RELEASE Posted: June 15, 2006 Development of Vega, Europe's new launcher for small payloads, continues at full speed. A dedicated test facility for the directional control system of the main engine has been completed and performance measurements are under way. The Vega development programme is performing a crucial series of tests during 2006, including engine firings, mechanical and electrical performance verifications, and system-level trials. Among the many test campaigns, measuring the performance of the control loop of Vega's first stage was started in May. Vega's first stage, known as P80, is a solid-fuel rocket motor which includes a Thrust Vector Control (TVC) system consisting of two electromechanical actuators that operate a movable nozzle. The TVC system moves the nozzle to control the pitch and yaw of the launcher (the attitude of the vehicle in relation to the flight direction) during flight. In order to characterise the TVC behaviour under the various conditions that could occur during flight and to verify the functionality of the control loop, a dedicated validation facility has been constructed at ELV SpA, in Colleferro (Italy). The TVC Validation Model allows examination of all aspects of system performance using fully representative hardware, specifically:
The design, manufacture and assembly of the components of the TVC Validation Model have been lead by Europropulsion SA, a jointly-owned subsidiary of Snecma Propulsion Solide (France) and Avio SpA (Italy), which is the Prime Contractor for the P80 main engine. The construction of the test plant, including mechanical parts and ground support equipment for electronic command and measurement acquisition, has been carried out under the responsibility of ELV SpA, the Prime Contractor for the Vega launch vehicle. The management of the P80 demonstrator programme is under the responsibility of the P80 Integrated Project Team (ASI , CNES and ESA), located at the CNES facility in Evry, France. The TVC subsystem tests are expected to last for several months. They will allow checking of the control sequence that will be used during the first P80 motor static firing test, scheduled to be conducted in Kourou during the last quarter of 2006. At a later stage, during the system test campaigns, the TVC Validation Model will also be used for overall system verification. It will be controlled by a test version of the Vega onboard computer and flight software, making use of the inertial measurement system simulator and the simulated flight dynamics environment. |
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Tony Ceccacci, the lead shuttle flight director for STS-121, provides a highly informative day-by-day preview of Discovery's mission using animation and other presentations. Then Rick LaBrode, the lead International Space Station flight director during STS-121, explains all of the activities occurring onboard and outside the outpost while Discovery visits.
Dial-up: 
Discovery's STS-121 mission to the International Space Station will feature two scheduled spacewalks and perhaps a third if consumables permit. Spacewalkers Mike Fossum and Piers Sellers will test whether the 50-foot inspection boom carried on the shuttle could be used as a work platform for repairing the heatshield and conduct maintenance chores outside the space station. Tomas Gonzalez-Torres, the mission's lead spacewalk officer, details all the three EVAs in this pre-flight news briefing.
A comprehensive series of press briefings for space shuttle Discovery's upcoming STS-121 begins with a program overview conference by Wayne Hale, NASA's manager of the shuttle program, and Kirk Shireman, the deputy program manager of the International Space Station. The two men discuss the significance of Discovery's mission to their respective programs. The briefing was held June 8 at the Johnson Space Center.
NASA officials unveil the plan to distribute work in the Constellation Program for robotic and human moon and Mars exploration. This address to agency employees on June 5 was given by Administrator Mike Griffin, Associate Administrator for the Exploration Systems Mission Directorate Scott Horowitz and Constellation Program Manager Jeff Hanley.
Following their announcement on the Exploration work assignments to the various NASA centers, Mike Griffin, Scott Horowitz and Jeff Hanley hold this news conference to answer reporter questions.