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This is the second paper in a two-part series presenting a sensitivity-analysis formulation covering configuration shape and structural sizing design variables for nonlinear thermostructural analysis including the effects of radiation: external and in internal cavities. Part 1 presented the steady-state coupled thermal-structural formulation with results from a new coupled design-oriented thermoelastic analysis capability. The present paper considers transient heat transfer analysis problems with temperature-dependent material properties. Structural response is assumed to be quasi-steady. Because structural--thermal integration had been demonstrated earlier, the focus here is on design-oriented analysis aspects of the conduction--radiation problem. An approximation scheme is presented for the category of problems discussed that leads to a reduction of CPU cost from the order of [N.sup.3] operations to [N.sup.2] for cavity radiation analysis. A hypersonic wing structure similar to a space shuttle wing is used as a test case.

The Air Force Institute of Technology is in the process of designing a space shuttle experiment designated as the Rigidized Inflatable Get-Away-Special Experiment (RIGEX) to study the effects of microgravity on the deployment of inflatable rigidizable composite structures. Once in space, the experiment is designed to inflate and rigidize three composite tubes (which could be used in a more global space structure), then perform a vibration analysis on each by exciting the structures using piezoelectric patches mounted to the walls of the tubes and collect data via accelerometers. The experiment is designed to take part in the National Aeronautics and Space Administration (NASA) get-away-special program and as such must meet structural verification standards to be pay loaded as such. This paper presents the structural and vibration analysis of the RIGEX assembly and inflatable composite tubes using ABAQUS finite-element analysis (FEA) software. Results of the FEA showed good correlation when compared to eigenvalue/eigenvector experimental results obtained from ping testing the actual structures. This finite-element analysis has been used to modify the experiments design to meet NASA structural integrity requirements and verify the natural frequency of the RIGEX structural support assemblies. CE Database subject headings: Structural design; Space shuttle orbiter; Experimentation.

Libration orbit stationkeeping controls are designed based on selected reference quasi-periodic orbit trajectories. The baseline trajectory is designed to meet science requirements and in the same time achieve minimum fuel consumptions. The success of finding libration point reference orbits is based on accurate numerical computation, dynamics, and space environment modeling. The linear quadratic regulator controller has been developed widely for maintaining a spacecraft in such libration orbit reference trajectories as close as possible. However, any dynamics models, including the circular restricted three-body dynamics, space environment, sensor, and actuator, are only approximations of real physical systems. Any noise and uncertainties can cause spacecraft' motion to diverge due to the high instability region around libration points. This study investigates the modeling and designing of a passive robust Ix controller and an active adaptive linear quadratic regulator in libration point stationkeeping controls around [L.sub.1]. The adaptive law in the linear quadratic regulator is used to estimate unknown gains of spacecraft' subsystems. The results are compared for a family of libration orbits with reasonable [DELTA]V yearly budgets under the influence of perturbations, noise, and unmodeled dynamics. The comparison with a publicly accessible work indicates that the controller developed in this work can provide comparable annual cost by nearly even including the worst case of perturbations. DOI: 10.1061/(ASCE)0893-1321 (2008)21:2(102) CE Database subject headings: Satellites; Space shuttle orbiter; Dynamics: Aerospace engineering.

The impact of ethics and values on technical events is discussed. The tragic accident of the Columbia space shuttle and the Challenger investigations are reviewed.

During the space shuttle era, policy makers have repeatedly wrestled with the issue of fleet size. The number of shuttles had both practical and symbolic significance, reflecting the robustness of the space transportation system and US preeminence in space. In debating how many shuttles were needed, NASA and other government entities weighed various arguments to determine the optimum number of vehicles for human spaceflight. Deliberations and decisions about shuttle fleet size reflected changing policy priorities and attitudes about the role of the shuttle. That history frames issues that may arise again in planning for new space transportation vehicles beyond the shuttle.

Byline: John Ledyard (1), David Porter (2), Randii Wessen (3) Keywords: mechanism design; auctions; scheduling Abstract: This is an investigation into the design of a market-based process to replace NASA's current committee process for allocating Shuttle secondary payload resources (lockers, Watts and crew). The market-based process allocates budgets of tokens to NASA internal organizations that in turn use the budget to bid for priority for their middeck payloads. The scheduling algorithm selects payloads by priority class and maximizes the number of tokens bid to determine a manifest. The results of a number of controlled experiments show that such a system tends to allocate resources more efficiently by guiding participants to make resource and payload tradeoffs. Most participants were able to improve their position over NASA's current ranking system. Furthermore, those that are better off make large improvements while the few that do worse have relatively small losses. Author Affiliation: (1) Division of Humanities and Social Sciences, California Institute of Technology, Pasadena, CA, 91125 (2) Economic Science Laboratory, University of Arizona, Tucson, AZ 85721 (3) Systems Division, Jet Propulsion Laboratory, Pasadena, CA, 91109 Article History: Registration Date: 03/10/2004

The steady progress of the NASA run International Space Station (ISS) program is discussed. The Orbital Space Plane (OSP) is being developed as the ISS lifeboat, which takes over crew transport duties between Earth and ISS from the remaining orbiters, whose average age is approaching 17 years

NASA began formal study with industry contractors in 1969 for a reusable spacecraft and they specified that the orbiter can deploy and retrieve satellites in orbit and return them to Earth inside the payload bay. NASA had to compromise on the final design of the space shuttle due to waning political will and a decreased budget. The Challenger and Columbia disasters led to the end of the winged reusable space plane.

Exploration Systems Architecture Study (ESAS) gives exact details of every part of the machines that would take the US back to the Moon and into LEO. National Aeronautics and Space Administration (NASA) administrator Mike Griffin selected Doug Stanley to head ESAS and direct its studies. ESAS defines the form of the versions of Crew Exploration Vehicle (CEV) both for crewed flights and cargo missions.

Funds allocated to NASA's space shuttle have been cut down as White House plans to pay for development of a new Crew Exploration Vehicle. There is high demand for F-22A Raptors from US Air Force and Bush administration. Under Future Cargo Aircraft program (FCA), the Army will be receiving Alenia C-27, CASA C-295 by replacing F-22A Raptors.

NASA's Kennedy Space Center scientists in Florida have to monitor tens of thousands of telemetry agents for pre-launch ground work of space shuttle. For round-the-clock monitoring they have developed and deployed a software, NASA Engineering Shuttle Telemetry Agent. The software will provide predefined patterns of interest and instantly notifying shuttle engineers via email or wireless page.

Severe conditions inside the space shuttle engine combustion cone cause the material that lines the combustion chamber to roughen. To solve this problem, scientists at NASA Marshall in Huntsville, Ala., developed an advanced vacuum plasma technique for spraying both coating and the liner onto a mold.