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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 specifications for the performance, design, development, and test requirements of the P2-156, S3-156, and S6-120 space shuttle booster solid rocket motors are presented. The applicable documents which form a part of the specifications are listed.
Procurement specifications to provide vendors of space systems with supporting information to accurately price the selected major buy items are illustrated. In performing this task, rigid constraints on specifications and drawing details are avoided beyond those necessary to define basic requirements. Described are digital processing equipment, mass spectrometer, body mass measuring device, sensors, bio-belt power source, vision tester and instrumentation for a biochemical station.
The mathematical specifications of the Goddard trajectory determination subsystem of the flight dynamics system are presented. These specifications include the mathematical description of the coordinate systems, dynamic and measurement model, numerical integration techniques, and statistical estimation concepts.
Experimental and theoretical study of the performance of a gas-core nuclear rocket, showing that in a uranium plasma nuclear rocket with an 8-ft cavity diameter the cavity wall can be cooled up to a power level of 7400 MW when the rocket operates at a pressure of 1000 atm and the propellant mass flow rate is 10 lbm/sec. A maximum cavity specific impulse of 5800 sec was obtained under such operating conditions. The fact that the wall heat flux was much lower for reactor powers below this level is linked to the presence of a relatively cool, opaque insulating layer of seeded propellant between the hot plasma and the solid wall. The additional coolant required for nozzle protection reduced the maximum cavity specific impulse to 5200 sec.
The specifications include applicable documents, requirements, and quality assurance provisions. The specifications also include results of earlier tasks of analysis and preliminary design.
Contract end item specifications required to define hardware end items for the expendable second stage on a reusable shuttle booster system are provided. The specifications are as follows: (1) expendable second stage, (2) space shuttle booster, and (3) space shuttle ground support system.
The specification for establishing the requirements for the system performance, design, development, and ground and flight operations of the expendable second stage on a reusable space shuttle booster system is presented. The basic specification is that the system shall be capable of placing payloads in excess of 100,000 pounds into earth orbit. In addition, the expendable second stage provides a multimission, economical, large capability system suitable for a variety of space missions in the 1980 time period.
The data set specifications for the NASA Aerospace Safety Information System (NASIS) are presented. The data set specifications describe the content, format, and medium of communication of every data set required by the system. All relevant information pertinent to a particular data set is prepared in a standard form and centralized in a single document. The format for the data set is provided.
The data set specifications for the NASA Aerospace Safety Information System (NASIS) are presented. The data set specifications describe the content, format, and medium of communication of every data set required by the system. All relevant information pertinent to a particular set is prepared in a standard form and centralized in a single document. The format for the data set is provided.
Thirty-eight subjects were required to execute 120 head movements in a slow rotation room at each 1-rpm increase in velocity of the room between 0 and 6 rpm and, after a single-step gradual return to zero velocity, execute 120 head movements either immediately after return or after delay periods varying from 1 to 24 hours unless, at any time, more than mild symptoms of motion sickness were elicited. A second stress profile differed by the sequential addition of an incremental adaptation schedule (identical to the first) in which the direction of rotation was reversed. The experimental findings demonstrated the acquisition of direction-specific adaptation effects that underwent spontaneous decay with a short time constant (hours). With their disappearance a nondirection-specific adaptation was revealed with a long-time constant (days). Speculations are presented which could account for the simultaneous acquisition of short-term and long-term adaptation effects.
The findings and data products developed during the crew interface specification study for inflight maintenance and stowage functions are presented. Guidelines are provided for improving the present progress of defining, controlling, and managing the flight crew requirements. The following data products were developed: (1) description of inflight maintenance management process, (2) specifications for inflight maintenance management requirements, and (3) suggested inflight maintenance data processing reports for logistics management.
A self contained, specific wavelength, single beam colorimeter is described for direct spectrophotometric measurement of the concentration of a given solute in a test sample. An electrical circuit employing a photoconductive cell converts the optical output into a linear, directly readable meter output. The colorimeter is simple to operate and is adapted for use in zero gravity conditions. In a specific application, the colorimeter is designed to analyze the concentration of iodine in potable water carried aboard a space vehicle such as the 4B stage of Skylab.
The detailed functional specifications presented are written as requirements for software implementation of the language and the program modules, and are aimed at a specific audience.
The test specifications for spacecraft and components permit test levels to be reduced under a procedure commonly referred to as notching. A summary is provided of the steps required to comply with the notching criterion. Primary structural loads are discussed along with aspect of mathematical modelling of the spacecraft structure, a launch loads analysis, a vibration test loads analysis, and notching methods. It is shown that current, general vibration test specifications are capable of producing unrealistically high spacecraft structural loads.
In order to produce cost effective environmental test programs, the test specifications must be realistic and to be useful, they must be available early in the life of a program. This paper describes a method for achieving such specifications for subsystems by utilizing the results of a statistical analysis of data acquired at subsystem mounting locations during system level environmental tests. The paper describes the details of this statistical analysis. The resultant recommended levels are a function of the subsystems' mounting location in the spacecraft. Methods of determining this mounting 'zone' are described. Recommendations are then made as to which of the various problem areas encountered should be pursued further.
The entry guidance software functional requirements (requirements design phase), its architectural requirements (specifications design phase), and the entry guidance software verified code are discussed. It was found that the proper integration of designs at both the requirements and specifications levels are of high priority consideration.
Findings and data products developed during crew specification study for inflight maintenance and stowage functions are reported. From this information base, a family of data concepts to support crew inflight troubleshooting and corrective maintenance activities was developed and specified. Recommendations are made for the improvement of inflight maintenance planning, preparations and operations in future space flight programs through the establishment of an inflight maintenance organization and specific suggestions for techniques to improve the management of the inflight maintenance function.
The use of adiabatic relations in the calculation of planetary atmospheres requires knowledge of the ratio of specific heats of a mixture of gases under various pressure and temperature conditions. It is shown that errors introduced by simple averaging of the ratio of specific heats in a multicomponent atmosphere can be roughly 0.4%. Therefore, the gamma-averaging error can become important when integrating through the atmosphere to a large depth.