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The application of law to the determination of what constitutes safeness is discussed. The numerous factors are analyzed which enter into the decisions of courts in deciding what is safe and what is unsafe. It is pointed out that as technology changes, legal interpretations of safety also change. Arguements are given for the use of system safety techniques and better engineering analyses as instruments of defense against liability.
Discussion of the concept and implications of back contamination and of the ways and means for its prevention. Back contamination is defined as contamination of the terrestrial biosphere with organisms or materials returned from outer space that are capable of potentially harmful terrestrial activity. Since the question of whether or not life exists on other planets may, in reality, not be answered until many samples are returned to earth for detailed study, requirements for the prevention of back contamination are necessary. A review of methods of microbiologic contamination control is followed by a discussion of the nature of back contamination and its risk levels, contamination sources and locations, and possible defenses against back contamination. The U.S. lunar back contamination program is described and shown to provide a valuable basis for further refining the technology for the control of planetary back contamination.
Failure mode, effects and criticality analyses were developed by NASA as a means of assuring that hardware built for space applications has the desired reliability characteristics. The failure mode and effects analysis is a qualitative reliability technique for systematically analyzing each possible failure mode within a hardware system, and identifying the resulting effect on that system, the mission and personnel. The criticality analysis is a quantitative procedure which ranks the critical failure modes according to their probability of occurrence. This paper describes the failure modes, effects analysis and the criticality analysis. It employs a simple hardware system, not related to the aerospace field, to illustrate the method. It encourages application of this type of analysis to industrial development programs outside the aerospace and defense complex.
This document is a compilation of papers presented at a Conference on the Medical Results of the First U.S. Manned Suborbital Space Flight. This conference was held by the NASA, in cooperation with the National Institutes of Health and the National Academy of Sciences, at the U.S. Department of State Auditorium on June 6, 1961. The papers were prepared by representatives of the NASA Space Task Group in collaboration with personnel from various Department of Defense medical installations, the University of Pennsylvania, and McDonnell Aircraft Corporation.
The author has identified the following significant results. The DCS water-stage data from the USGS streamflow gaging station on the Verde River near Camp Verde furnished information sufficient for the accurate computation of daily mean streamflow rates during the first 2 months of operation. Daily mean flow rates computed from the DCS data agreed with those computed from the digital recorder data within + or - 5% during periods of stable or slowly changing flow and within + or - 10% during periods of rapidly changing high flow. The SRP was furnished near-real time DCS information on snow moisture content and streamflow rates for use in the management and operation of the multiple-use reservoir system. The SRP, by prudent water management and the use of near-real time hydrologic data furnished by microwave and ERTS DCS telemetry, was successful in anticipating the amount of flow into the Salt and Verde Rivers and in the subsequent release of water at rates that did not create flooding in metropolitan Phoenix. Only minor flooding occurred along the Gila River west of Phoenix. According to the Maricopa County Civil Defense agency, wage and salary losses of about $11,400,000 resulted from closing of roads across the Salt River in the winter and spring of 1972-73; however, the number and duration of the closing were minimized by use of DCS data.
The tables of schedules and descriptions which portray the 1973 NASA Payload Model are presented. The schedules cover all NASA programs and the anticipated requirements of the user community, not including the Department of Defense, for the 1973 to 1991 period. The descriptions give an indication of what the payload is expected to accomplish, its characteristics, and where it is going. The payload flight schedules shown for each of the discipline areas indicate the time frame in which individual payloads will be launched, serviced, or retrieved. These do not necessarily constitute shuttle flights, however, since more than one payload can be flown on a single shuttle flight depending on size, weight, orbital destination, and the suitability of combining them. The weight, dimension, and destination data represent approximations of the payload characteristics as estimated by the Program Offices. Payload codes are provided for easy correlation between the schedules and descriptions of the Payload Model and subsequent documentation which may reference this model.
Apollo program experience in recovery-support communications is reviewed, and the working relationships among NASA, the Department of Defense, and commercial communications facilities are discussed. The organization, facilities, philosophy, and funding of recovery-support communications are described. The relocation of two recovery control centers is discussed, as are the functions of primary and secondary recovery ships, aircraft, and relay satellities. The possibility of using ships of opportunity for recovery operations is considered. Finally, the means by which money, manpower, and resources have been saved and longlines leased are delineated.
The aeronomy group at the University of Pittsburgh is actively engaged in a series of coordinated satellite, sounding rocket, and laboratory studies designed to expand and clarify knowledge of the physics and chemistry of planetary atmospheres. Three major discoveries have been made that will lead ultimately to a complete and dramatic revision of our ideas on the ionospheres of Mars, Venus, and the Earth and on the origin of their vacuum ultraviolet airglows. The results have already suggested a new generation of ionosphere studies which probably can be carried out best by laser heterodyning techniques. Laboratory studies have also identified, for the first time, the physical mechanism responsible for the remarkable nitric oxide buildup observed in some auroral arcs. This development is an important break-through in auroral physics, and has military ramifications of considerable interest to the Department of Defense. This work may also shed some light on related NO and atomic nitrogen problems in the mesosphere.
The orbiter ECLSS (Environmental Control and Life Support System) provides the functions of atmosphere revitalization, crew life support, and active thermal control. This paper describes these functions as they relate to the support of Shuttle payloads, including automated spacecraft, Spacelab and Department of Defense missions. Functional and performance requirements for the orbiter ECLSS which affect payload support are presented for the atmosphere revitalization subsystem, the food, water and waste subsystem, and the active thermal control subsystem. Schematics for these subsystems are also described. Finally, based on the selected orbiter configuration, preliminary design and off-design thermodynamic data are presented to quantify the baseline orbiter capability; to quantify the payload chargeable penalties for increasing this support; and to identify the significant limits of orbiter ECLSS support available to Shuttle payloads.
A British defense communications satellite is discussed for launch into synchronous orbit over the Indian Ocean aboard a NASA Delta three-stage launch vehicle from Cape Canaveral.
Defense Mapping Agency timing requirements ranging from milliseconds to tenths of nanoseconds and its use of geodetic astronomy and satellite geodesy programs are discussed in detail.
Two prototype systems of The Automated Astronomic Positioning System (AAPS) have been delivered to Defense Mapping Agency (DMA). The AAPS was developed to automate and expedite the determination of astronomic positions (latitude and longitude). This equipment is capable of defining astronomic positions to an accuracy sigma = 0.3 in each component within a two hour span of stellar observations which are acquired automatically. The basic concept acquires observations by timing stellar images as they cross a series of slits, comparing these observations to a stored star catalogue, and automatically deducing position and accuracy by least squares using pre-set convergence criteria. An exhaustive DMA operational test program has been initiated to evaluate the capabilities of the AAPS in a variety of environments (both climatic and positional). Status of the operational test is discussed.
In the Frequency and Time Standard Development Program of the TIMATION System, a new miniaturized rubidium vapor frequency standard has been tested and analyzed for possible use on the TIMATION 3A launch, as part of the Defense Navigation Satellite Development Program. The design and construction of a digital frequency control was required to remotely control this rubidium vapor frequency standard as well as the quartz oscillator in current use. This control must be capable of accepting commands from a satellite telemetry system, verify that the correct commands have been sent and control the frequency to the requirements of the system. Several modifications must be performed to the rubidium vapor frequency standard to allow it to be compatible with the digital frequency control. These include the addition of a varactor to voltage tune the coarse range of the flywheel oscillator, and a modification to supply the C field current externally. The digital frequency control for the rubidium vapor frequency standard has been successfully tested in prototype form.
During 1972 time transfer experiments were run between the U.S. Naval Observatory and the Royal Greenwich Observatory and, in 1973, between the U.S. Naval Observatory and the Division of National Mapping in Canberra, Australia. In both cases the time transfer agent was the TIMATION 2 satellite, 1969-82B. The satellite ephemerides were computed from data provided by the Defense Mapping Agency TRANET. This net tracked the satellite's Doppler transmissions. The phase of the satellite clock was determined from knowledge of the position of the satellite and of the observer and the computed distance between the two. By monitoring the clock on successive passes the rate of the satellite clock was determined at Washington. By again monitoring the satellite clock at the distant station the satellite clock could be compared to the local clock and this local clock compared to the U.S. Naval Observatory clocks. In 1972 the RMS of observations at Greenwich deviated by approximately 1/4 microsecond from a straight line when compared to the Naval Observatory. In 1973 the observation errors at Canberra were approximately half as great.
The Defense Communication System will be moving rapidly toward providing switched digital service to it's users within the next ten years. The principal driving force in the transition to a digital system is the requirement for high performance secure voice service. Additionally, the anticipated data requirements in this time frame can be handled most effectively by a digital network. The characteristics of a switched digital network which impose timing and synchronization requirements on the system design are presented. Several alternative approaches to implementing a timing subsystem suitable for a switched digital communications system have been considered. These include pulse stuffing, independent stable clocks, and clock correction techniques. The advantages and disadvantages of each approach are discussed relative to both the strategic and tactical communication system requirements.
The underlying philosophy of the general approach to failure reduction and control is presented. Safety and reliability management techniques developed in the industries which have participated in the U.S. space and defense programs are described along with adaptations to nonaerospace activities. The examples given illustrate the scope of applicability of these techniques. It is indicated that any activity treated as a 'system' is a potential user of aerospace safety and reliability management techniques.
Current demand for aeronautical engineers is approximately balanced with supply, with some shortfall in certain specialties. In the near term (5 years), demand will exceed supply of new graduates. A number of factors have brought on the state of imbalance: (1) the cyclic nature of the demand of our defense requirements; (2) drastic changes in DOD aircraft procurement; (3) the emergence of the space age; (4) evolution of social attitudes toward technology with resultant decline in enrollments; and (5) the universities themselves through their influences in the direction of careers selected by engineers. These factors have been counteracted somewhat by increased DOD emphasis on aircraft development programs but more importantly by the favorable growth in civil aircraft requirements.
A general description of the space shuttle program is presented, with emphasis on its application to the use of space for commercial, scientific, and defense needs. The following aspects of the program are discussed: description of the flight system (orbiter, external tank, solid rocket boosters) and mission profile, direct benefits related to life on earth (both present and expected), description of the space shuttle vehicle and its associated supporting systems, economic impacts (including indirect benefits such as lower inflation rates), listing of participating organizations.