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Space rendezvous propulsion system requirements - phase and mission analyses, and propulsion system design requirements
Quick-opening lightweight solenoid hammer valve requires a low amount of electrical energy to open, and closes by the restoring action of the mechanical springs. This design should be applicable to many quick-opening requirements in fluid systems.
The purpose of this paper is to review some of the more recent simulator results with emphasis on the airplane-design problem areas. Some of the simulator requirements for V/STOL and a low-altitude attack airplane will also be presented. Areas requiring additional effort are discussed briefly. Simulators for crew training however, are not considered in this paper.
This document presents the development requirements, costs, and schedule for a high-energy upper-stage hybrid propulsion system. High energy is achieved through the use of a lithium fuel formulation (solid) and fluorinated oxidizer (liquid). The propulsion system contains 3 2OO lb of propellant and may be used as a terminal stage for Atlas/Centaur or DSV-3M Delta launch vehicle. A program to develop a fluorinated hybrid propulsion system could be initiated with little risk. An extensive investigation revealed that the technology required to develop most of the components has either been demonstrated or is in progress. Further, it was found that there were no areas of critical technology. The cost to develop a hybrid propulsion system to a status where it could be integrated into a flight-test stage is about $17 million. This cost does not include the development of the stage astrionics. Length of the total development program is 34 months. A total recurring cost of $381 600 was estimated for the first unit (less astrionics and fee). This includes purchased hard\rare, manufacturing, material, assembly, and test costs.
Systems engineering and requirements analyses of Manned Orbiting Research Laboratory /MORL/, discussing typical laboratory size, volume and crew requirements
Space mission requirements for the 70's have established a 50,000-hour-lifetime challenge for the mechanisms designer. This challenge may be met by two approaches: (1) development of new materials for wear-prone elements, and (2) design innovation of new electromechanical devices that do not include mechanical wear-prone components. Present state-of-the-art materials require restricted operation regarding load, speed, and power for gears, bearings, and brush-slipring components. These restrictions are discussed, and methods of improvement are suggested. The design-innovations approach is discussed and is illustrated by the design of an experimental magnetically suspended motor.
The impulsive, high thrust missions portion of a study on guidance and navigation requirements for unmanned flyby and swingby missions to the outer planet is presented. The proper balance between groundbased navigational capability, using the deep space network (DSN) alone, and an onboard navigational capability with and without supplemental use of DSN tracking, for unmanned missions to the outer planets of the solar system is defined. A general guidance and navigation requirements program is used to survey parametrically the characteristics associated with three types of navigation systems: (1) totally onboard, (2) totally Earth-based, and (3) a combination of these two.
The guidance and navigation requirements for a set of impulsive thrust missions involving one or more outer planets or comets. Specific missions considered include two Jupiter entry missions of 800 and 1200 day duration, two multiple swingby missions with the sequences Jupiter-Uranus-Neptune and Jupiter-Saturn-Pluto, and two comets rendezvous missions involving the short period comets P/Tempel 2 and P/Tuttle-Giacobini-Kresak. Results show the relative utility of onboard and Earth-based DSN navigation. The effects of parametric variations in navigation accuracy, measurement rate, and miscellaneous constraints are determined. The utility of a TV type onboard navigation sensor - sighting on planetary satellites and comets - is examined. Velocity corrections required for the nominal and parametrically varied cases are tabulated.
The interface requirements between the modular space station (MSS) and the space shuttle cover both the ground and orbital phases of operation from the launch of the first MSS module until the initial modular station has been manned and in routine operation. As a point of reference, the NR two-stage, fully reusable space shuttle, whose definition has been obtained from the space shuttle Phase B definition studies, has been selected around which the interface requirements have been described.
The interface and support performance, design and confirmation requirements are defined for the modular space station and space shuttle programs. The requirements are treated as separate obligations against each modular program and are presented for the following: shuttle orbiter, shuttle booster, launch operations, mission operations, and the research applications module.
The results are summarized of a study to determine the requirements of a data management system to meet the needs of MSC in mission planning and program and resource management during the 1975 time frame. The study addresses overall system requirements, implementation considerations, and cost/benefit comparisions.
Government-sponsored study and development efforts were directed toward design and implementation of high level programming languages suitable for future aerospace applications. The study centered around an evaluation of the four most pertinent existing aerospace languages. Evaluation criteria were established, and selected kernels from the current Saturn 5 and Skylab flight programs were used as benchmark problems for sample coding. An independent review of the language specifications incorporated anticipated future programming requirements into the evaluation. A set of language requirements was synthesized from these activities.
Investigations were conducted to evaluate the relative benefits attainable through the exploitation of advanced technologies and to identify future research and development efforts required to permit the application of selected technologies to transport aircraft entering commercial operation in 1985. Results show that technology advances, particularly in the areas of composite materials, supercritical aerodynamics, and active control systems, will permit the development of long-range, high-payload commercial transports operating at high-subsonic speeds with direct operating costs lower than those of current aircraft. These advanced transports also achieve lower noise levels and lower engine pollutant emissions than current transports. Research and development efforts, including analytical investigations, laboratory test programs, and flight test programs, are required in essentially all technology areas to achieve the potential technology benefits.
A study was conducted to develop the means to identify skills required of scientist passengers on advanced missions related to the space shuttle and RAM programs. The scope of the study was defined to include only the activities of on-orbit personnel which are directly related to, or required by, on-orbit experimentation and scientific investigations conducted on or supported by the shuttle orbiter. A program summary is presented which provides a description of the methodology developed, an overview of the activities performed during the study, and the results obtained through application of the methodology.
Activities are documented of the study to determine skills required of on-orbit crew personnel of the space shuttle. The material is presented in four sections that include: (1) methodology for identifying flight experiment task-skill requirements, (2) task-skill analysis of selected flight experiments, (3) study results and conclusions, and (4) new technology.
Safety requirements and guidelines are listed for the sortie module, upper stage vehicle, and space station for the earth orbit operations of the space shuttle program. The requirements and guidelines are for vehicle design, safety devices, warning devices, operational procedures, and residual hazards.
The justification and requirements are summarized for a large subsonic wind tunnel capable of testing full-scale aircraft, rotor systems, and advanced V/STOL aircraft propulsion systems. The design considerations and constraints for such a facility are reviewed, and the trades between facility test capability and costs are discussed. The design studies showed that the structural cost of this facility is the most important cost factor. For this reason (and other considerations such as requirements for engine exhaust gas purging) an open-return wind tunnel having two test sections was selected. The major technical problem in the design of an open-return wind tunnel is maintaining good test section flow quality in the presence of external winds. This problem has been studied extensively, and inlet and exhaust systems which provide satisfactory attenuation of the effects of external winds on test section flow quality were developed.
Computational requirements - i.e., computing time per cycle (iteration) and required storage - which determine minimum sampling rates and computer memory size, were obtained as functions of the dimensions of the important system matrices for a discrete Kalman filter. Two types of measurement processing are discussed: simultaneous and sequential. It is shown that it is often better to process statistically independent measurements in more than one batch and then use sequential processing than to process them together via simultaneous processing.