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The objectives, functions, and organization of the Deep Space Network are summarized. The Deep Space Instrumentation Facility, the Ground Communications Facility, and the Space Flight Operations Facility are described.
Research on aircraft-generated sonic booms has led to the development of special techniques to generate controlled sonic-boom-type disturbances without the complications and expense of supersonic flight operations. This paper contains brief descriptions of several of these techniques along with the significant hardware items involved and indicates the advantages and disadvantages of each in research applications. Included are wind tunnels, ballistic ranges, spark discharges, piston phones, shock tubes, high-speed valve systems, and shaped explosive charges. Specialized applications include sonic-boom generation and propagation studies and the responses of structures, terrain, people, and animals. Situations for which simulators are applicable are shown to include both small-scale and large-scale laboratory tests and full-scale field tests. Although no one approach to simulation is ideal, the various techniques available generally complement each other to provide desired capability for a broad range of sonic-boom studies.
Discussion of preventive or remedial systems to achieve safer space flight operations. Escape, rescue, and survival systems are defined by categories: on board, prepositioned aid, and earth-launched concepts. The survey considers separable escape or survival capsules; standby escape or rescue systems; and earth-launched manned and unmanned rescue systems. Reports covering such systems are listed, and the contents are classified as to scope of investigation, space mission, and design approach. Mission classes considered are earth orbit, lunar, and interplanetary. Results of the space escape, rescue, and survivability investigations are summarized in terms of system features and performance, including apparent voids or limitations in rescue capability. Recovery requirements and resources for space rescue are discussed.
Preventive and remedial conceptual approaches may be employed to enhance the safety of space flight operations. The preventive approach makes use of components of high reliability and the incorporation of redundancy in crew safety-related functions. According to the second conceptual approach the means are to be provided to cope with accidents when they arise. The remedial means include onboard systems, pre-positioned aids, and earth-launched systems. Reports or papers dealing with rescue and survival systems of various types are considered, and a summary of the results of space escape, rescue, and survivability investigations is presented.
Spectrophotometry of the Mg II resonance doublet at 2795.5 and 2802.7 A has been performed for five stars with a balloon-borne telescope and spectrometer. Spectral resolution attained was between 0.25 and 0.5 A. A description of the payload and flight operations is given. In beta Lyr the Mg II doublet displayed P Cygni characteristics, while in gamma Lyr the doublet was observed only in absorption. The star beta Cas shows broad overlapping Mg II absorption lines with possible weak emission at the line bottom. In alpha CMi, both components of the doublet are seen in emission at the bottom of the broad absorption feature. The Mg II doublet in alpha Ori is entirely in emission, with each component showing distinct self-reversal.
The Pioneer Space Probe Project is explained to document the events which occurred during the project. The subjects discussed are: (1) origin and history of interplanetary Pioneer program, (2) Pioneer system development and design, (3) Pioneer flight operations, and (4) Pioneer scientific results. Line drawings, circuit diagrams, illustrations, and photographs are included to augment the written material.
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.
Analysis and results are given for the position determination accuracy obtainable from the microwave landing guidance system. Siting arrangements, coverage volumes, and accuracy standards for the azimuth, elevation, and range functions of the microwave system are discussed. Results are given for the complete coverage of the systems and are related to flight operational requirements for position estimation during flare, glide slope, and general terminal area approaches. Range rate estimation from range data is also analyzed. The distance measuring equipment accuracy required to meet the range rate estimation standards is determined, and a method of optimizing the range rate estimate is also given.
A basic model is presented for estimating the cost of unmanned lunar and planetary programs. Cost data were collected and analyzed for eight lunar and planetary programs. Total cost was separated into the following components: labor, overhead, materials, and technical support. The study determined that direct labor cost of unmanned lunar and planetary programs comprises 30 percent of the total program cost. Twelve program categories were defined for modeling: six spacecraft subsystem categories (science, structure, propulsion, electrical power, communications, and guidance and integration, test and quality assurance, launch and flight operations, ground equipment, systems analysis and engineering, and program management). An analysis showed that on a percentage basis, direct labor cost and direct labor manhours compare on a one-to-one ratio. Therefore, direct labor hours is used as the parameter for predicting cost, with the advantage of eliminating the effect of inflation on the analysis.
The mission of Mariner 9, the first spacecraft to orbit another planet, was to make scientific observations of the surface of Mars. Throughout this unique mission, the Mariner 9 solar array successfully supported the power requirements of the spacecraft without experiencing anomalies. Basically, the design of the solar array was similar to those of Mariners 6 and 7; however, Mariner 9 had the additional flight operational requirement to perform in a Mars orbit environment mode. The array special tests provided information on the current-voltage characteristics and array space degradation. Tests indicated that total solar array current degradation was 3.5 percent, which could probably be attributed to the gradual degradation of the cover glass and/or the RTV 602 adhesive employed to cement the cover glass to the solar cell.
The longitudinal, lateral, and directional aerodynamic characteristics of two space shuttle concepts have been obtained in helium for operational flight Reynolds numbers at angles of attack from minus 10 to 55 deg. Included are elevon control deflections, roll control due to ailerons, and the effects of a nose modification. Selected results were compared with those derived from tangent-cone and Newtonian theories. Also included are results of a flow-visualization study consisting of electron-beam-illuminated flow and surface oil-flow patterns.
The noise of older aircraft can be reduced in two principal ways: retrofitting the aircraft with a quiet propulsion system, and changing the flight operational procedures used in flying the aircraft. The former approach has already proved to be expensive, time consuming, and difficult to implement even though low-noise propulsion system technology exists. The latter method seems to hold promise of being less expensive and easier to implement. One operational technique which might reduce the noise beneath the landing approach path is the decelerating approach. This technique requires intercepting the 3 deg approach path at a relatively high speed with the aircraft in the cruise configuration, then reducing the thrust to idle and allowing the aircraft to decelerate along the 3 deg approach path. As the appropriate airspeed is achieved, the landing flaps and landing gear are deployed for a normal flare and landing. Because the engines, which are the predominant noise source on landing approach, are at idle thrust, a significant reduction in the noise beneath the approach path should be realized.
A space vehicle's response to atmospheric disturbances includes many parameters, the choice of criteria (parameters) depending upon the vehicle configuration and the specific mission. Response calculation methods for all phases of vehicle design are separated into their various phases and parts, using different approaches and methods of evaluation, as the particular phase demands. Although not independent, these phases include: (1) preliminary design; (2) final structural design; (3) guidance and control system design and optimization (preliminary and final); and (4) establishment of limits and procedures for launch and flight operations. Thus, the proper selection, representation, and use of wind information require the skillfully coordinated efforts of aerospace meteorologists and engineers.
The Deep Space Network (DSN) activities in support of Project Apollo during the period of 1971 and 1972 are reported. Beginning with the Apollo 14 mission and concluding with the Apollo 17 mission, the narrative includes, (1) a mission description, (2) the NASA support requirements placed on the DSN, and, (3) a comprehensive account of the support activities provided by each committed DSN deep space communication station. Associated equipment and activities of the three elements of the DSN (the Deep Space Instrumentation Facility (DSIF), the Space Flight Operations Facility (SFOF), and the Ground Communications Facility (GCF)) used in meeting the radio-metric and telemetry demands of the missions are documented.
Multispectral mapping accomplishments using the M7 airborne scanner are summarized. The M7 system is described and overall results of specific data collection flight operations since June 1971 are reviewed. A major advantage of the M7 system is that all spectral bands of the scanner are in common spatial registration, whereas in the M5 they were not.
The application of the existing Agena vehicle as a reusable upper stage for the space shuttle is discussed. The primary objective of the study is to define those changes to the Agena required for it to function in the reusable mode in the 100 percent capture of the NASA-DOD mission model. This 100 percent capture is achieved without use of kick motors or stages by simply increasing the Agena propellant load by using optional strap-on-tanks. The required shuttle support equipment, launch and flight operations techniques, development program, and cost package are also defined.
The operational flight instrumentation required for performance monitoring and fault detection are presented. Measurements by the burn through monitors are presented along with manifold and helium source pressures.
The mathematical model considers a large particle (m sub 1), such as a space station, and a smaller particle (m sub 2), connected by an ideal, massless tether, i.e., one incapable of sustaining other than tensile loads. The problem situation described offers a practical solution which should be quite useful in certain space flight operations, especially for the transfer of cargo and personnel and for retrieval and rescue operations. The idea is simple in its application and does not appear to require sophisticated hardware. An appealing advantage is that it is infinitely reusable, i.e., it could be rewound and used over and over again.