GP-B Post-Flight Analysis—Final Report - Gravity Probe B - Stanford ...

positive thermal connections between the inner and outer bands, thus meeting the needs of the experiment.Rather than returning Probe C to LM for this modification, it was decided that the work would be done atStanford so that members of the Stanford gyro team could replace gyro #4 at the same time.6.4.3 Repairing Flight Probe C & Replacing Gyro #4Having devised a conceptual solution for the repair of Probe C, Turneaure, who had been working tirelessly onGP-B hardware development since the mid 1980s decided to step back from the role of Program Manager.Everitt then appointed Sasha Buchman, a GP-B physicist and Co-Investigator who had been working closelywith Turneaure, as the new Program Manager, and Turneaure took a well-deserved sabbatical. Thus,Buchman's first task as GP-B Program Manager was to oversee the retrofitting of Probe C with copper pins tosolve the thermal contact problem, and to supervise the replacement of gyro #4 and the reintegration of Probe Cinto the dewar.At a Probe C repair review, held in March 2000, it was determined that the team was ready to implement theTurnearue/Reynolds copper pin solution, and the repairs to Probe C commenced. The repair work was carriedout in a Stanford clean room by the LM spacecraft team, under the supervision of Jeff Vanden Beukel. Inparallel, while the copper pins were being inserted in the upper portion of the probe, the vacuum cover wasremoved from the lower half of the probe, and gyro #4 was replaced by the Stanford gyro team. The copper pinthermal repairs were completed in May, and the replacement of gyro #4, along with some other minor repairs tothe probe were completed in September. Then, during the fall of 2000, Probe C was reintegrated into the SMDfor the last time.Parkinson’s transition in 1998 from Program Manager to Co-PI and Program Advisor resulted in his spendingmuch less time at GP-B thereafter, and this left the GP-B senior management team in need of an experiencedaerospace engineer on-site at Stanford. Early in 2000, a NASA Independent Review Team (IRT) mandated thatGP-B acquire a management-level consultant with considerable aerospace experience. To this end, Ron Singley,who had worked for many years at Lockheed Martin, was hired by GP-B later that year to serve in this capacity,helping Stanford improve their interactions with LM and aiding in the efficient development of the spacevehicle.6.4.4 Moving Towards Flight ReadinessBy early 2001, all of the major GP-B flight hardware problems had been solved, except for the Gas ManagementAssembly (GMA). Realizing that its team lacked the expertise to build a flight-ready gas management system,Stanford (with strong support from NASA) decided to contract out the development of this hardware. Stanfordconducted a brief, but thorough source-selection process, and in June 2001, selected Moog, Inc. in East Aurora,New York, to design and build a GMA system for GP-B. Moog had considerable experience building suchsystems, and they delivered a flight-certified GMA system just 13 months later, in August 2002. Much creditgoes to Stanford’s lead engineer, Chris Gray and to Lockheed Martin engineering manager, Jeff Vanden Beukel,for making this happen in an extremely responsive manner.Many other milestones were also accomplished in 2001-2002, including an acoustic vibration test of theintegrated payload, completion of the space vehicle at LM, and integration of the payload with the spacecraft. Inaddition, the payload electronics boxes—TRE, SRE, and ECU—were completed and installed in mid 2002, aswas the new GSS electronics system. Equally important, work had begun in 2000 setting up the GP-B MissionOperations Center at Stanford, from which the spacecraft and payload would be monitored and controlled onceit was in orbit. Likewise, work on mission operations procedures, training, and simulations commenced in 2000and continued through mid 2003.158 March 2007 Chapter 6 — The GP-B Management Experiment