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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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The scientific objectives were considered for a Phobos/Deimos mission. The payloads for a minimum useful instrument complement were developed. The rationale for a sample return mission is discussed, along with the scientific constraints and requirements for the acquisition of samples.
Combined missions to Mars and Phobos/Deimos were considered in relation to large scientific returns at a low total cost. A matrix of all feasible major combined mission concepts was compiled. The most promising approach was selected from which a nominal mission profile was developed. A systems analysis was performed to trade off performance, configuration, and cost characteristics of candidate mission concepts. Configuration and subsystem optimization analysis were then conducted from which a baseline and an alternate program were selected. Program schedules and cost estimates were prepared for the recommended and alternate program.
For abstract, see .
For abstract see N72-27933
Analytical trade studies are presented that consider passive TPS configurations using the following material categories: (1) reuseable surface insulation - surface-coated rigidized ceramic fiber; (2) low density charring ablators; and (3) carbon-carbon and high density ablators for leading edge areas. Emphasized are effects on TPS weight by variations in entry trajectories and material thermal characteristics.
A program was undertaken regarding the economic benefits attainable through the application of advanced technologies to the next generation of long-range transport aircraft in the Mach number range from 0.85 to 1.0. In addition to airframe studies, two parallel engine systems studies contracts are also in progress. The manufacturability of composites promises structural concepts which can take forms very similar to those employed in conventional structures or forms very different from conventional approaches. It is pointed out that the findings of the studies discussed justify a considerably expanded effort not only in composite materials but also in other technologies.
Study has been made to assure maximum utility of storage space and crew member facilities in planned space shuttle orbiter. Techniques discussed in this study should be of interest to designers of storage facilities in which space is at premium and vibration is severe. Manufacturers of boats, campers, house trailers, and aircraft could benefit from it.
The simulation developments for use in dynamics and control analysis during boost from liftoff to orbit insertion are reported. Also included are wind response studies of the NR-GD 161B/B9T delta wing booster/delta wing orbiter configuration, the MSC 036B/280 inch solid rocket motor configuration, the MSC 040A/L0X-propane liquid injection TVC configuration, the MSC 040C/dual solid rocket motor configuration, and the MSC 049/solid rocket motor configuration. All of the latest math models (rigid and flexible body) developed for the MSC/GD Space Shuttle Functional Simulator, are included.
A review of user requirements and updated instrumentation plans are presented for the aircraft tracking and guidance facility at NASA Wallops Station. User demand has increased as a result of new flight research programs; however, basic requirements remain the same as originally reported. Instrumentation plans remain essentially the same but with plans for up- and down-link telemetry more firm. With slippages in the laser acquisition schedule, added importance is placed on the FPS-16 radar as the primary tracking device until the laser is available. Limited simulation studies of a particular Kalman-type filter are also presented. These studies simulated the use of the filter in a helicopter guidance loop in a real-time mode. Disadvantages and limitations of this mode of operation are pointed out. Laser eyesafety calculations show that laser tracking of aircraft is readily feasible from the eyesafety viewpoint.
Supporting information for the ERS loading study contains computer simulation loading output including printout description, and similar output representing data that include night station contacts.
A Tracking and Data Relay Satellite System (TDRSS) concept for service of low and medium data rate user spacecraft has been defined. The TDRS system uses two geosynchronous dual spin satellites compatible with Delta 2914 to provide command, tracking, and telemetry service between multiple low earth orbiting users and a centrally located ground station. The low data rate user service capability via each TDRS is as follows: (1) forward link at UHF: voice to one user, commands to 20 users (sequential), range and range rate service, and (2) return link at VHF: voice from one user, data from 20 users (simultaneous), range and range rate return signals. The medium data rate user service via each TDRS is as follows: (1) forward link at S band: voice or command and tracking signals to one user, and (2) return link at S band: voice, data and tracking signals from one user "order wire" for high priority service requests (implemented with an earth coverage antenna).
The baseline Tracking and Data Relay Satellite telecommunication system is described. The configurations of the user spacecraft terminal and the ground based terminal are illustrated. The system service and performance summary is developed to show the link support, modes of operation, and link performance to the low data rate and medium data rate user spacecraft. The link budget calculation is included to show a typical computation for each space-to-space and space-to-ground link with the assumptions used in each calculation.
For abstract, see N74-22706.
The investigation of single actuator failures on the space shuttle solid rocket booster required the analysis of both square pattern and diamond pattern actuator configurations. It was determined that for failures occuring near or prior to the region of maximum dynamic pressure, control gain adjustments can be used to achieve virtually nominal mid-boost vehicle behavior. A distinct worst case failure condition was established near staging that could significantly delay staging. It is recommended that the square pattern be retained as a viable alternative to the baseline diamond pattern because the staging transient is better controlled resulting in earlier staging.
A users guide to the Sampled Data Stability Analysis Program (SADSAP) is provided. This program is a general purpose sampled data Stability Analysis Program capable of providing frequency response on root locus data.
An optimum powered explicit guidance algorithm capable of handling all space shuttle exoatospheric maneuvers is presented. The theoretical and practical basis for the currently baselined space shuttle powered flight guidance equations and logic is documented. Detailed flow diagrams for implementing the steering computations for all shuttle phases, including powered return to launch site (RTLS) abort, are also presented. Derivation of the powered RTLS algorithm is provided, as well as detailed flow diagrams for implementing the option. The flow diagrams and equations are compatible with the current powered flight documentation.
The results are reported of the Pioneer Venus studies from 2 October 1972 through 30 June 1973. Many missions were considered, involving two launch vehicles (Thor/Delta and Atlas/Centaur), and different launch opportunities and spacecraft configurations to meet varying science requirements, all at minimum cost. The sequence of events is described and the specific studies conducted are summarized. The effects of science payload on mission and spacecraft design are discussed along with the mission analyses.
The aerodynamic design problems for the Pioneer Venus mission are discussed for a small probe shape that enters the atmosphere, and exhibits good stability for the subsonic portion of the flight. The problems discussed include: heat shield, structures and mechanisms, thermal control, decelerator, probe communication, data handling and command, and electric power.