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A symposium was conducted on the practical applications of earth resources survey technology including utilization and results of data from programs involving LANDSAT, the Skylab earth resources experiment package, and aircraft. Topics discussed include geological structure, landform surveys, energy and extractive resources, and information systems and services.
The design, evaluation, and testing of a practical, multivariable, linear quadratic regulator control for the F100 turbofan engine were accomplished. NASA evaluation of the multivariable control logic and implementation are covered. The evaluation utilized a real time, hybrid computer simulation of the engine. Results of the evaluation are presented, and recommendations concerning future engine testing of the control are made. Results indicated that the engine testing of the control should be conducted as planned.
A brief manual control test and a decision strategy were developed, laboratory tested, and field validated which provide a means for detecting human operator impairment from alcohol or other drugs. The test requires the operator to stabilize progressively unstable controlled element dynamics. Control theory and experimental data verify that the human operator's control ability on this task is constrained by basic cybernetic characteristics, and that task performance is reliably affected by impairment effects on these characteristics. Assessment of human operator control ability is determined by a statistically based decision strategy. The operator is allowed several chances to exceed a preset pass criterion. Procedures are described for setting the pass criterion based on individual ability and a desired unimpaired failure rate. These procedures were field tested with apparatus installed in automobiles that were designed to discourage drunk drivers from operating their vehicles. This test program demonstrated that the control task and detection strategy could be applied in a practical setting to screen human operators for impairment in their basic cybernetic skills.
As gas turbine technology continues to advance, the need for advanced life prediction methods for hot section components is becoming more and more evident. The complex local strain and temperature histories at critical locations must be accurately interpreted to account for the effects of various damage mechanisms (such as fatigue, creep, and oxidation) and their possible interactions. As part of the overall NASA HOST effort, this program is designed to investigate these fundamental damage processes, identify modeling strategies, and develop practical models which can be used to guide the early design and development of new engines and to increase the durability of existing engines.
The need for advanced life prediction methods for hot section components for gas turbine engines is becoming more and more evident. The complex local strain and temperature histories at critical locations must be accurately interpreted to account for the effects of various damage mechanisms and their possible interactions. This program is designed to investigate these fundamental damage processes, identify modeling strategies, and develop practical models which can be used to guide the early design and development of new engines and to increase the durability of existing engines.
During the flight program on the Bell X-5 airplane with 59 deg sweepback to determine the practical Mach number and normal-force coefficient limits of this configuration, a reduction in static longitudinal stability was encountered in maneuvering flight. A determination of the boundary for reduction of longitudinal stability extending to a Mach number of 0.98 is presented in this paper. A reduction of static longitudinal stability existed for all elevator and all stabilizer-executed maneuvers. The reduction of stability existed for maneuvers executed with elevator near a normal-force coefficient of 0.6 for a Mach number range of about 0.31 to 0.76. Above a Mach number of 0.76 the normal-force coefficient for reduction of stability gradually decreased to a value of 0.2 at a Mach number of 0.98. For stabilizer-executed maneuvers the stability boundary was the same as for elevator maneuvers up to a Mach number of 0.88. Above this Mach number the reduction of stability occurred at slightly higher normal-force coefficients decreasing from about 0.51 at a Mach number of 0.92 to a value of 0.311 at a Mach number of 0.97. The airplane has been flown to a Mach number of 1.04 at a normal-force coefficient of about 0.15 without encountering any reduction of stability. The pilot did not consider the reduction of stability to be dangerous at altitudes above 30,000 feet; however, precise flight was impossible. At angles of attack above that at which the reduction of longitudinal stability occurred, directional instability and aileron control overbalance were encountered.
Present interest in hypersonic vehicles has resulted in a renewed interest in thermal stress analysis of airframe structures. While there are numerous texts and papers on thermal stress analysis, practical examples and experience on light gage aircraft structures are fairly limited. A research program has been undertaken at General Dynamics to demonstrate the present state of the art, verify methods of analysis, gain experience in their use, and develop engineering judgement in thermal stress analysis. The approach for this project has been to conduct a series of analyses of this sample problem and compare analysis results with test data. This comparison will give an idea of how to use our present methods of thermal stress analysis, and how accurate we can expect them to be.
The goal of this program was the development of a SiC CVD growth of films thick enough to be useful as pseudo-substrates. The cold-walled CVD system was designed, assembled, and tested. Extrapolating from preliminary evaluation of SiC films grown in the system at relatively low temperatures indicates that the growth rate at the final temperatures will be high enough to make our approach practical. Modifications of the system to allow high temperature growth and cleaner growth conditions are in progress. This program was jointly funded by Wright Laboratory, Materials Directorate and NASA LeRC and monitored by NASA.
Natural space and atmospheric environments pose a difficult challenge for designers of technological systems in space. The deleterious effects of environment interactions with the systems include degradation of materials, thermal changes, contamination, excitation, spacecraft glow, charging, radiation damage, and induced background interference. Design accommodations must be realistic with minimum impact on performance while maintaining a balance between cost and risk. The goal of applied research in space environments and effects is to limit environmental impacts at low cost relative to spacecraft cost and to infuse enabling and commercial off-the-shelf technologies into space programs. The need to perform applied research to understand the space environment in a practical sense and to develop methods to mitigate these environment effects is frequently underestimated by space agencies and industry. Applied science research in this area is critical because the complexity of spacecraft systems is increasing, and they are exposed simultaneously to a multitude of space environments.
Achieving laminar flow on the wings of a commercial transport involves difficult problems associated with the wing leading edge. The NASA Leading Edge Flight Test Program has made major progress toward the solution of these problems. The effectiveness and practicality of candidate laminar flow leading edge systems were proven under representative airline service conditions. This was accomplished in a series of simulated airline service flights by modifying a JetStar aircraft with laminar flow leading edge systems and operating it out of three commercial airports in the United States. The aircraft was operated as an airliner would under actual air traffic conditions, in bad weather, and in insect infested environments.
A Point Doppler Velocimeter (pDv) has been developed using a vapor-limited iodine cell as the sensing medium. The iodine cell is utilized to directly measure the Doppler shift frequency of laser light scattered from submicron particles suspended within a fluid flow. The measured Doppler shift can then be used to compute the velocity of the particles, and hence the fluid. Since this approach does not require resolution of scattered light from individual particles, the potential exists to obtain temporally continuous signals that could be uniformly sampled in the manner as a hot wire anemometer. This leads to the possibility of obtaining flow turbulence power spectra without the limitations of fringe-type laser velocimetry. The development program consisted of a methodical investigation of the technology coupled with the solution of practical engineering problems to produce a usable measurement system. The paper outlines this development along with the evaluation of the resulting system as compared to primary standards and other measurement technologies.
The NASA Engineering and Safety Center was requested to improve on the Best Practices document produced for the NESC assessment, Verification of Probabilistic Requirements for the Constellation Program, by giving a recommended procedure for using acceptance sampling by variables techniques. This recommended procedure would be used as an alternative to the potentially resource-intensive acceptance sampling by attributes method given in the document. This document contains the outcome of the assessment.
The NASA Engineering and Safety Center was requested to improve on the Best Practices document produced for the NESC assessment, Verification of Probabilistic Requirements for the Constellation Program, by giving a recommended procedure for using acceptance sampling by variables techniques as an alternative to the potentially resource-intensive acceptance sampling by attributes method given in the document. In this paper, the results of empirical tests intended to assess the accuracy of acceptance sampling plan calculators implemented for six variable distributions are presented.
The Mars Program has recently been informed of the Planetary Protection Subcommittee (PPS) recommendation, which was endorsed by the NAC, concerning Mars Science Lab (MSL) lessons learned and knowledge capture. The Mars Program has not had an opportunity to consider any decisions specific to the PPS recommendation. Some of the activities recommended by the PPS would involve members of the MSL flight team who are focused on cruise, entry descent & landing, and early surface operations; those activities would have to wait. Members of the MSL planetary protection team at JPL are still available to support MSL lessons learned and knowledge capture; some of the specifically recommended activities have already begun. The Mars Program shares the PPS/NAC concerns about loss of potential information & expertise in planetary protection practice.
The Federal Energy Management Program's (FEMP's) Federal Smart Buildings Accelerator team identified many smart campus best practices already in place, along with several new goals for the Department of Commerce's National Institute of Standards and Technology (NIST) Gaithersburg campus.
Maturity models can be used to provide government agencies, industry associations, and organizations operating nuclear facilities with the ability to quickly evaluate the maturity of their cybersecurity programs and identify areas to prioritize for improvement. The Cybersecurity Capability Maturity Model (C2M2) was developed by the U.S. Department of Energy to allow organizations in the energy sector to evaluate the programmatic capabilities of their cybersecurity programs in a consistent manner, communicate programmatic maturity information, prioritize cybersecurity investments in targeted areas of concern, and track how the maturity of their cybersecurity program evolves over time. The C2M2 is designed for use by any critical infrastructure organization regardless of ownership, structure, or size. The C2M2 can be easily fine-tuned to access the maturity of nuclear cybersecurity programs and their application at individual facilities. Built on a foundation of existing cybersecurity standards, frameworks, programs, and initiatives, the model features 10 security domains. Performance in each security domain is characterized using a structured set of cybersecurity practices that represent activities an organization can perform to improve cybersecurity in their domain. Each practice can be quickly evaluated as being either fully, largely, partially, or not implemented. Once practices are evaluated for each security domain, the model defines four maturity indicator levels that apply independently to each domain in the model. To earn a maturity level in a given domain, an organization must adequately perform all the practices for that maturity level and its predecessor level(s). A small assessment team can conduct a C2M2 assessment in a single day. A screening version of the C2M2 allows an initial look at the maturity of nuclear cybersecurity programs that could be completed in under an hour.
In late 2016, the U.S. Army Corps of Engineers (USACE) implemented a Headquarters-supported nationwide records management initiative managed by the USACE-New England District to address the digitization and organization of Formerly Utilized Sites Remedial Action Program (FUSRAP) project files. This initiative will prepare USACE FUSRAP for moving toward a fully electronic system of records management. Additionally, the records management initiative streamlines the process and prepares the Administrative Record (AR) and Permanent Record (PR) file for transfer from USACE to the U.S. Department of Energy (DOE)-Office of Legacy Management (LM) following project closeout. Over the past couple of years, USACE and DOE-LM have been working to finalize a joint guidance document to assist in the FUSRAP records transition process. However, there remain key records management topics that require further discussion and development. Specifically, these topics include the implementation, process, and procedure for the capture of social media records and compliance with Section 508 of the Rehabilitation Act of 1973 (29 USC 794d), as amended. Due to advances in technology and the ease of communication it provides, USACE is using social media more often to interface with the public than 5, 10 or 15 years ago. The identification and capture of these records are challenging because it requires each USACE district or producer of a record to track what has been released through social media so that it can be captured as part of the AR or PR. USACE is currently evaluating processes and procedures for social media records capture. This paper explores how social media is being used by USACE across FUSRAP projects and best practices for the capture of social media records. Public accessibility to the project AR is required under the Comprehensive Environmental Response, Compensation, and Liability Act, which USACE FUSRAP must follow. As USACE FUSRAP ARs are converted to a digital format, greater accessibility to the files can be provided through web sites or other electronic media. However, Section 508 of the Rehabilitation Act must be considered when releasing electronic files to the public. Under Section 508, government agencies must ensure that information is made available to the public in a format that provides equal access to persons with disabilities. This paper discusses the electronic records requirements under Section 508 and addresses broad implementation of compliance across large digital records sets. Records management challenges are presented in the context of the FUSRAP records management program; however, these records management considerations and best practices are applicable across all Federal agency records management programs. Examples presented will further aid in understanding electronic records requirements that may be included on new USACE FUSRAP contracts as well as upcoming National Archives Records Administration requirements that will move us toward an electronic government. (authors)
NASA Marshall Space Flight Center (MSFC) has designed, built, and is currently testing Fastrac, a liquid oxygen (LOX)/RP-1 fueled 60K-lb thrust class rocket engine. One facet of Fastrac, which makes it unique is that it is the first large-scale engine designed and developed in accordance with the Agency's mandated "faster, better, cheaper" (FBC) program policy. The engine was developed under the auspices of MSFC's Low Cost Boost Technology office. Development work for the main injector actually began in 1993 in subscale form. In 1996, work began on the full-scale unit approximately 1 year prior to initiation of the engine development program. In order to achieve the value goals established by the FBC policy, a review of traditional design practices was necessary. This internal reevaluation would ultimately challenge more conventional methods of material selection. design process, and fabrication techniques. The effort was highly successful. This "new way" of thinking has resulted in an innovative injector design, one with reduced complexity and significantly lower cost. Application of lessons learned during this effort to new or existing designs can have a similar effect on costs and future program successes.