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Critical inclinations in satellite theory
The main problem of satellite theory is described in polar coordinates by a Hamiltonian function. It is proposed to find a solution of the Hamiltonian function with the following properties: (1) the reference orbit is Keplerian; (2) no restriction is imposed on the eccentricity; in particular, it is exempt of singularities - real or apparent - for small eccentricities; and (3) no restriction is imposed on the inclination; in particular, it is exempt of singularities - real or apparent - for small inclinations; also it is valid even in the neighborhood of inclinations at which the perigee is stationary.
An Investigation Into Criteria Commonly Used by the FAA to Grant Relief to Part 135 Operators Under FAR Sections: 135.213, 135.219, and/or 135.225
The objective of this study was to determine the criteria commonly used by the FAA to grant waivers, exemptions, or deviations to FAR Part 135, Sections 135.213, 135.219, and 135.225 and the potential impact on Flight Information Services Data Link (FISDL) implementation. These aviation regulations address the requirements for the use of weather reports or forecasts when conducting operations under FAR Part 135. In this study a literature search was conducted to obtain historical records of requests for relief from the 3 FAR sections under consideration. The exemption request records were then analyzed in order to determine the reasons given by the FAA for either granting or denying the request. In addition, FAA personnel and Part 135 operators were interviewed to determine the procedures used for satisfying the requirements of the 3 FAR sections.
Mobile Timekeeping Application Built on Reverse-Engineered JPL Infrastructure
Every year, non-exempt employees cumulatively waste over one man-year tracking their time and using the timekeeping Web page to save those times. This app eliminates this waste. The innovation is a native iPhone app. Libraries were built around a reverse- engineered JPL API. It represents a punch-in/punch-out paradigm for timekeeping. It is accessible natively via iPhones, and features ease of access. Any non-exempt employee can natively punch in and out, as well as save and view their JPL timecard. This app is built on custom libraries created by reverse-engineering the standard timekeeping application. Communication is through custom libraries that re-route traffic through BrowserRAS (remote access service). This has value at any center where employees track their time.
Metrication study for large space telescope
Various approaches which could be taken in developing a metric-system design for the Large Space Telescope, considering potential penalties on development cost and time, commonality with other satellite programs, and contribution to national goals for conversion to the metric system of units were investigated. Information on the problems, potential approaches, and impacts of metrication was collected from published reports on previous aerospace-industry metrication-impact studies and through numerous telephone interviews. The recommended approach to LST metrication formulated in this study cells for new components and subsystems to be designed in metric-module dimensions, but U.S. customary practice is allowed where U.S. metric standards and metric components are not available or would be unsuitable. Electrical/electronic-system design, which is presently largely metric, is considered exempt from futher metrication. An important guideline is that metric design and fabrication should in no way compromise the effectiveness of the LST equipment.
Medical operations: Crew surgeon's report
To assure the safety and well being of the Skylab environment simulation crewmembers it was necessary to develop a medical safety plan with emergency procedures. All medical and nonmedical test and operations personnel, except those specifically exempted, were required to meet the medical standards and proficiency levels as established. Implemented programs included health care of the test crew and their families, occupational medical services for chamber operating personnel, clinical laboratory support and hypobaric and other emergency support.
Lithium cell technology and safety report of the Tri-Service Lithium Safety Committee
The organization of the Tri-Service Lithium Safety Committee is described. The following areas concerning lithium batteries are discussed: transportation--DOT Exemption 7052, FAA; disposal; storage; individual testing/test results; and battery design and usage.
The rules implementing sections 201 and 210 of the Public Utility Regulatory Policies Act of 1978: A regulatory history
The act provides that utilities must purchase power for qualifying producers of electricity at nondiscriminatory rates. It exempts private generators from virtually all state and federal utility regulation. Pertinent reference material is provided.
Line-oriented flight training: Northwest Airlines
An exemption from certain FAA regulations which stereotype simulator flight training was obtained and pilots with current line experience were used to prepare and develop scenarios for a program in which each crew member would be trained to recognize and properly use all available resouces. The development of the scenarios for training to proficiency and pilot reaction to the training sessions are discussed.
Radiation effects response data for synthetic organic insulation and dielectrics
Existing radiation response data for 130 materials of the synthetic organic insulation and dielectric class are analyzed, and thresholds and 25-percent change dose levels for these materials are presented. Both the lowest reported threshold dose (LTD) and the 25-percent change dose level are found to vary widely among the different insulators (used as spacecraft components). The LTD is tabulated to indicate the levels where radiation effects become apparent. These level are of use in setting a lower limit where changes can be expected, and could be used to exempt synthetic insulation and dielectrics from radiation considerations when the environments are substantially below this limit. Cautions to be observed in applying the data to current problems are presented.
A new licensing strategy for Canadian mobile earth stations
Initiatives presently under consideration by the Department of Communications which will greatly simplify the licensing process for mobile earth stations are addressed. The current licensing approach is reviewed and the limitations of that system identified. A new approach is needed to respond to the needs of mobile satellite users in the 1990's and beyond, one which will have a minimal impact on the user while still respecting the legislative responsibilities of the department under the new Radiocommunication Act and the General Radio Regulations. The objective of this new strategy is to lead to a transparent licensing scheme for the end user, which in turn could lead to license exemption of blanket licenses as soon as possible.
In defense of compilation: A response to Davis' form and content in model-based reasoning
In a recent paper entitled 'Form and Content in Model Based Reasoning', Randy Davis argues that model based reasoning research aimed at compiling task specific rules from underlying device models is mislabeled, misguided, and diversionary. Some of Davis' claims are examined and his basic conclusions are challenged about the value of compilation research to the model based reasoning community. In particular, Davis' claim is refuted that model based reasoning is exempt from the efficiency benefits provided by knowledge compilation techniques. In addition, several misconceptions are clarified about the role of representational form in compilation. It is concluded that techniques have the potential to make a substantial contribution to solving tractability problems in model based reasoning.
Training effectiveness assessment: Where are we?
Over 9,000 pilot training courses have been conducted at FSI using the Bell 222 and Sikorsky S-76 simulators. Through the use of FAA exemptions, these simulators can be used for certain training and checking credit. The history of the development and use of commercial helicopter simulators and the opportunities for their increased utilization and use were explored.
Progress through precedent: Going where no helicopter simulator has gone before
Helicopter simulators have been approved by means of special exemption; there are no FAA standards for simulators used in training or airmen Certification checking. The fixed-wing industry provides a precedent which can be used for expediting implementation of helicopter simulators. The analysis in this paper is founded on the experience with that precedent and is driven by a clear definition of helicopter user needs for (1) improved training at lower cost, (2) more comprehensive emergency training at lower risk, (3) increased fidelity of transition and instrument training compared with low-cost aircraft alternatives, and (4) certification credit for improved simulator training.
Generic Propellants Transfer Unit (GPTU)
The Generic Propellants Transfer Unit (GPTU) is being designed to support spacecraft liquid propellant operations at the Kennedy Space Center (KSC) and Eastern Test Range (ETR). The GPTU will have a 500 gallon capacity and be Department Of Transportation (DOT) approved for over-the-road transportation of hypergolic propellants. The use of these containers will allow the users to increase efficiency and reduce the following costs: design/construction, transportation (to/from the launch site), propellant transfer operations, and decontamination operations. The user also acquires the flexibility of transporting to an offsite location for processing or storage without obtaining special exemptions or permits. These containers will incorporate their own quantity gaging and temperature sensing systems, and be integrated onto a transport trailer which contains work platforms and a fluid transfer system.
Methyl Chloroform Elimination from the Production of Space Shuttle Sold Rocket Motors
Thiokol Space Operations manufactures the Reusable Solid Rocket Motors used to launch America's fleet of Space Shuttles. In 1989, Thiokol used more than 1.4 Mlb of methyl chloroform to produce rocket motors. The ban placed by the Environmental Protection Agency on the sale of methyl chloroform had a significant effect on future Reusable Solid Rocket Motor production. As a result, changes in the materials and processes became necessary. A multiphased plan was established by Thiokol in partnership with NASA's Marshall Space Flight Center to eliminate the use of methyl chloroform in the Reusable Solid Rocket Motor production process. Because of the extensive scope of this effort, the plan was phased to target the elimination of the majority of methyl chloroform use (90 percent) by January 1, 1996, the 3 Environmental Protection Agency deadline. Referred to as Phase I, this effort includes the elimination of two large vapor degreasers, grease diluent processes, and propellant tooling handcleaning using methyl chloroform. Meanwhile, a request was made for an essential use exemption to allow the continued use of the remaining 10 percent of methyl chloroform after the 1996 deadline, while total elimination was pursued for this final, critical phase (Phase II). This paper provides an update to three previous presentations prepared for the 1993, 1994, and 1995 CFC/Halon Alternative Conferences, and will outline the overall Ozone Depleting Compounds Elimination Program from the initial phases through the final testing and implementation phases, including facility and equipment development. Processes and materials to be discussed include low-pressure aqueous wash systems, high-pressure water blast systems- environmental shipping containers, aqueous and semi-aqueous cleaning solutions, and bond integrity and inspection criteria. Progress toward completion of facility implementation and lessons learned during the scope of the program, as well as the current development efforts and basic requirements of future methyl chloroform handcleaning elimination, will also be outlined.
Engineering Registration-Why Bother?
This paper describes the benefits of obtaining the credentials of Professional Engineer (PE) also known as Registered Engineer, and Engineer in Training (EIT) also known as Engineering Intern; necessary preparation and preparation tools (i.e. tutorial, study guides, review classes, sample questions), the application process, and information for both graduates and undergraduates who seek their PE/EIT. Also included will be updates on the government and industry exemptions; what has NSPE (National Society for Professional Engineers) done for me lately; comments about long and short term effects of NAFTA on the practice of engineering, and information about state to state registration differences, focusing on the six southeastern states of Alabama, Florida, Georgia, Kentucky, Mississippi, and Tennessee.
Advanced Finite Element Modeling of Low Cycle Fatigue Crack Growth
This document (a viewgraph presentation) assumes a crack-like defect of a size which may be missed in inspection will exist in most critical location of any critical structure or component. Flaw existence assumption is usually, but not always, conservative based on past experiences in NASA and knowledge of manufacturing processes. Cyclic, environmental, and sustained loads used to generate stresses on models. Fracture Mechanics analysis used to predict crack growth and residual strength. Must show that defective structure will still provide four times required mission lifetime. Special exemptions cover redundant structures, low risk parts, etc. Assessments require specialized software tools, experienced analysts, and reliable material crack growth rate test database.