Search NASA⌕ Search

SEARCH · Search NASA

Results for “LIABILITIES”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9

The magnetic state of the Earth (according to the magnetic maps for 1880.0 published by the German Naval Office)

Publication of the magnetic maps in 1880 has made it possible to make the first continuation of the foundations for the Earth's magnetism established by Gauss in the general theory of Earth magnetism. A new calculation based on the maps valid for 1880, makes it possible to express the changes which have occurred over the last 50 years in numbers and only within the liability limits of the maps themselves.

Icilius, G. V. Q.↗

Guidelines for assessment and control of noise

There is an obvious need for guidelines and standards with respect to what intensities and durations of noise exposure is considered incompatible with the health and well-being of the people exposed. These guidelines would presumably be useful for the zoning of land areas to avoid overexposure of people to environmental noise and for legislative-judicial adjudication of liabilities for possible damages to individuals and groups from exposure to noise. A number of guidelines for noise exposure were promulgated by various governmental agencies for these purposes. Partly because of the need for an integrated and consistent program of noise control for all elements of the government, the United States Environmental Protection Agency (EPA) was established. In addition to previously issuing some specific documents regarding safe noise exposure limits, the EPA joined several Federal operating and regulatory agencies in issuing guidelines for considering noise in land use planning and control. Government guideline documents, as well as some issued by non-government agencies, are examined. Also, newly proposed guidelines for noise in residential areas, and the scientific basis for these guidelines, are presented.

Source record↗

Conflict resolution maneuvers during near miss encounters with cockpit traffic displays

The benefits and liabilities associated with pilots' use of a cockpit traffic display to assess the threat posed by air traffic and to make small maneuvers to avoid situations which would result in collision avoidance advisories are experimentally studied. The crew's task was to fly a simulated wide-body aircraft along a straight course at constant altitude while intruder aircraft appeared on a variety of converging trajectories. The main experimental variables were the amount and quality of the information displayed on the intruder aircraft's estimated future position. Pilots were to maintain a horizontal separation of at least 1.5 nautical miles or a vertical separation of 500 ft, so that collision avoidance advisories would not be triggered. The results show that pilots could usually maneuver to provide the specified separation but often made course deviations greater than 1.5 nm or 500 ft.

Palmer, E.↗

Self-separation in terminal areas using CDTI

The Langley Research Center is participating in a joint NASA/FAA program designed to explore the potential benefits and liabilities of Cockpit Display of Traffic Information (CDTI) for a broad range of applications. As a part of this effort, part-task piloted simulations have been conducted to determine the effect of various display parameters and separation criteria on terminal area in-trail following using CDTI. Current experiments are evaluating cockpit procedures and crew workload aspects of self-separation tasks in a simulated full-system terminal area environment. This paper will summarize the results of the part-task terminal area experiments and discuss the current full-system simulation experiments involving active self-separation tasks.

Williams, D. H.↗

Design principles for high efficiency small-grain polysilicon solar cells, with supporting experimental studies

Design principles suggested here aim toward high conversion efficiency (greater than 15 percent) in polysilicon cells. The principles seek to decrease the liabilities of both intragranular and grain-boundary-surface defects. The advantages of a phosphorus atom concentration gradient in a thin (less than 50 microns) base of a p(+)/n(x)/n(+) drift-field solar cell, which produces favorable gradients in chemical potential, minority-carrier mobility and diffusivity, and recombination lifetime (via phosphorus gettering) are suggested. The degrading effects of grain boundaries are reduced by these three gradients and by substituting atoms (P, H, F or Li) for vacancies on the grain-boundary surface. From recent experiments comes support for the benefits of P diffusion down grain boundaries and, for quasi-grain-boundary-free and related structures. New analytic solutions for the n(x)-base include the effect of a power-law dependence between P concentration and lifetime. These provide an upper-bound estimate on the open circuit voltage. Finite-difference numerical solutions of the six Shockley equations furnish complete information about all solar-cell parameters and add insight concerning design.

Lindholm, F. A.↗

The structures and the role of an international agency for the control of satellites

Legal questions involved in the liability of a proposed agency which would control internationally owned satellites for monitoring worldwide compliance with arms control agreements are discussed. Difficulties in acquiring the signed consent of all the relevant nations, and guaranteeing satisfactory compliance with the terms of such an agreement are noted. Additional problems to be solved comprise the construction of the ground based facilities and the satellites, the funding for the venture, and the reconciliation of the functions of the proposed agency with the sovereignty of individual states. The agency would gather, treat, and format data for signatories of arms control agreements and provide technical assistance in crisis conditions. It is concluded that the existence and functioning of the agency would reduce the amount of classified information and would consequently reduce the level of international tensions.

Dupuy, R. J.↗

Construction and application of a questionnaire for the social scientific investigation of environmental noise effects

A social psychological questionnair has been developed to study the effects of environmental noise and was applied to 636 people living in 19 different areas of Hamburg. The theoretical foundations and the statistical means employed in its development are described. Four main reactions to noise are isolated statistically, and it is determined that these are moderated by several intervening variables, chief of which are coping capacity for noise, the perceived dangerousness of the noise souce, other daily loads and the individual's liability.

Guski, R.↗

NASA and the practice of space law

The paper discusses the need for increased awareness in space law due to advances in space technology and a trend toward commercialization of space. A list of national and international treaties, conventions, agreements, laws, and regulations relevant to space activities is presented. NASA lawyers specialize in international and municipal laws that affect the NASA space mission; an example of the lawyers working with insurance companies in negotiating the first Space Shuttle liability policy is provided. The increased participation of the public sector in space activities, for example, the commercialization of the Space Shuttle transportation system, is examined.

Hosenball, S. N.↗

Evaluation of the usefulness of various simulation technology options for TERPS enhancement

Current approved terminal instrument procedures (TERPS) do not permit the full exploitation of the helicopter's unique flying characteristics. Enhanced TERPS need to be developed for a host of non-standard landing sites and navigation aids. Precision navigation systems such as microwave landing systems (MLS) and the Global Positioning System (GPS) open the possibility of curved paths, steep glide slopes, and decelerating helicopter approaches. This study evaluated the feasibility, benefits, and liabilities of using helicopter cockpit simulators in place of flight testing to develop enhanced TERPS criteria for non-standard flight profiles and navigation equipment. Near-term (2 to 5 year) requirements for conducting simulator studies to verify that they produce suitable data comparable to that obtained from previous flight tests are discussed. The long-term (5 to 10 year) research and development requirements to provide necessary modeling for continued simulator-based testing to develop enhanced TERPS criteria are also outlined.

Phatak, A. V.↗

A study of factors related to commercial space platform services

In the past four years, the issue of the commercial development of space has come to the forefront of the U. S. national space policy. Though the Administration, Congress and NASA have all shown strong support for encouraging the private sector to become more actively involved in the commercial utilization of space, the question remains whether they must do more to foster the creation and development of a viable U. S. commercial space industry. Marketing aspects, insurance and risk loss, tax related factors, space transportation, termination liability, institutional barriers, and procurement laws and regulations are discussed.

Hosenball, S. N.↗

The Space Station - Past, present and future with some thoughts on some legal questions that need to be addressed

The history of the concept of a space station is briefly considered, taking into account a story written by Hale (1869), quantitative work provided by Oberth and Tsiolkovsky, von Braun, and the U.S. decision regarding the establishment of a space station. Arguments in favor of constructing a space station are related to the utility of a laboratory in earth orbit, the importance of a repair and maintenance base for satellites, the provision of capabilities for the commercial utilization of space, and the employment of a space station as a staging base for missions to the moon, Mars, and, possibly, the asteroids. Plans for the implementation of the Space Station concept are discussed, taking into account also legal issues involved in such an implementation. Attention is given to questions regarding the applicability of the Liability convention, U.S. domestic law, the domestic law of other countries, and four treaties.

Hosenball, S. N.↗

Proposed upgrade of the Deep Space Network research and development station

Continued exploration of the solar system will require continued evolution of capabilities to support deep space communication and navigation. That evolution will rely, as it has in the past, on the development, demonstration, and field testing of communication and navigation technologies. The existing Deep Space Network (DSN) research and development station, DSS 13, at the Venus site, Goldstone, California was instrumental in those prior developments. However, the present antenna is no longer able to provide the necessary support for technology. The 26 meter antenna has good performance at S-band, fair performance at X-band, but is unusable at the anticipated Ka-band. It is not suitable for conversion to beam waveguides, and is not usable as a test bed for demonstrating high efficiency because of structural pliancy. Additionally, its size and age are increasingly a liability in demonstrations. A 34 meter beam waveguide version of the existing DSN high efficiency (HEF) antennas was proposed for FY-88 Construction of Facilities budget. The antenna is to be built at the Venus site, adjacent to the old antenna, and serve as the DSN research and development antenna through the end of the century.

Smith, Joel G.↗

Simulating Instrument Helicopter Takeoffs And Landings

Advantages and disadvantages of computer-based simulations reviewed. Report reviews current methods for evaluation of TERP's. Discusses feasibility, benefits, liabilities of substitution of electronically controlled flight-simulation equipment for flight tests.

Phatak, Anil V.↗

Insurance and indemnification implications of future space projects

NASA options regarding insurance and indemnification policies as they relate to NASA customers and contractors are described. The foundation for the discussion is the way in which NASA is planning to return the Space Shuttle fleet to safe flight as well as current U.S. policy concerning future uses of the Shuttle fleet. Issues discussed include: the nature of the Shuttle manifest; the policy regarding property damage or destruction; insurance against liability to third parties; the reduction of the scope of the risk to be insured; NASA as the insurer; a sharing arrangement between the user and NASA; and contractors and subcontractors involved in Shuttle operations.

O'Brien, John E.↗

A piloted simulation study of data link ATC message exchange

Data link Air Traffic Control (ATC) and Air Traffic Service (ATS) message and data exchange offers the potential benefits of increased flight safety and efficiency by reducing communication errors and allowing more information to be transferred between aircraft and ground facilities. Digital communication also presents an opportunity to relieve the overloading of ATC radio frequencies which hampers message exchange during peak traffic hours in many busy terminal areas. A piloted simulation study to develop pilot factor guidelines and assess potential flight crew benefits and liabilities from using data link ATC message exchange was completed. The data link ATC message exchange concept, implemented on an existing navigation computer Control Display Unit (CDU) required maintaining a voice radio telephone link with an appropriate ATC facility. Flight crew comments, scanning behavior, and measurements of time spent in ATC communication activities for data link ATC message exchange were compared to similar measures for simulated conventional voice radio operations. The results show crew preference for the quieter flight deck environment and a perception of lower communication workload.

Waller, Marvin C.↗

Design for validation: An approach to systems validation

Every complex system built is validated in some manner. Computer validation begins with review of the system design. As systems became too complicated for one person to review, validation began to rely on the application of adhoc methods by many individuals. As the cost of the changes mounted and the expense of failure increased, more organized procedures became essential. Attempts at devising and carrying out those procedures showed that validation is indeed a difficult technical problem. The successful transformation of the validation process into a systematic series of formally sound, integrated steps is necessary if the liability inherent in the future digita-system-based avionic and space systems is to be minimized. A suggested framework and timetable for the transformtion are presented. Basic working definitions of two pivotal ideas (validation and system life-cyle) are provided and show how the two concepts interact. Many examples are given of past and present validation activities by NASA and others. A conceptual framework is presented for the validation process. Finally, important areas are listed for ongoing development of the validation process at NASA Langley Research Center.

Carter, William C.↗

Commercial ELV services and the National Aeronautics and Space Administration - Concord or discord?

In implementation of the U.S. policy to foster and encourage the commercial expendable launch vehicle (ELV) industry, tensions have developed between the industry and U.S. Government agencies in two distinct areas: industry use of government facilities and government purchase of commercial ELV services. The reasons for the tensions and discrete legal problems for each area are identified and discussed. Specifically, in the use of government facilities area, issues of insurance and indemnification for third-party liability and government property, concerns over priority and scheduling, and dispute-resolution procedures are discussed. In the area of government purchase of ELV launch services, a comparison is made between a launch service purchase and prior procurement practice. In all areas, the conclusion is reached that while problems still exist, they generally are understood and great progress has been made toward their resolution.

Frankle, Edward A.↗

Report of the NASA lunar energy enterprise case study task force

The Lunar Energy Enterprise Cast Study Task Force was formed to determine the economic viability and commercial business potential of mining and extracting He-3 from the lunar soil for use in earth-based fusion reactors. In addition, the Solar Power Satellite (SPS) and the Lunar Power Station (LPS) were also evaluated because they involve the use of lunar materials and could provide energy for lunar-based activities. The Task Force considered: (1) the legal and liability aspects of the space energy projects; (2) the long-range terrestrial energy needs and options; (3) the technical maturity of the three space energy projects; and (4) their commercial potential. The use of electricity is expected to increase, but emerging environmental concerns and resource availability suggest changes for the national energy policy. All three options have the potential to provide a nearly inexhaustible, clean source of electricity for the U.S. and worldwide, without major adverse impacts on the Earth's environment. Assumption by industry of the total responsibility for these energy projects is not yet possible. Pursuit of these energy concepts requires the combined efforts of government and industry. The report identifies key steps necessary for the development of these concepts and an evolving industrial role.

Source record↗