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Of the many research approaches investigated over the years to measure the lubrication properties of aviation turbine fuels, the Ball-on-Cylinder Lubricity Evaluator (BOCLE) has emerged as the most significant test. BOCLE was originally a lubricant research device modified for low viscosity jet fuel when the Air Force encountered fuel control problems in 1965 with JP-4. It proved to be capable of detecting the presence of additives such as corrosion inhibitors which improve boundary lubrication properties and also the absence of natural lubricity agents in highly refined jet fuel. The Coordinating Research Council carried out several programs to investigate test variables such as cylinder type, humidity control and load. A semi-automated version using Falex test rings has now been commercialized and is being used to test fuels from aircraft experiencing abnormal pump wear and fuel control hang-up.

There have been some air carrier concerns that basic aviator skills are atrophying due to the increasing use of automation in all phases of airline operation. We will examine three systems where automation has greatly influenced crew activity, outline our concerns, and discuss how we are addressing those concerns.

The status of the hypersonic research program at Stanford University is discussed and recent results are highlighted. The main areas of interest in the program are the numerical simulation of radiating, reacting and thermally excited flows, the investigation and numerical solution of hypersonic shock wave physics, the extension of the continuum fluid dynamic equations to the transition regime between continuum and free-molecule flow, and the development of novel numerical algorithms for efficient particulate simulations of flowfields.

Inviscid flow fields have been computed for blunt axisymmetric shapes exposed to a hypersonic environment. A fully implicit scheme using a flux vector splitting technique was used to obtain a finite difference formulation. To increase computational efficiency, an approximate factorization scheme was used. Flow-field solutions were obtained for chemically reacting air using a decoupled approach. Flow fields were computed for blunted, flared shapes over a range of Mach numbers from 2 to 20.

This report is a brief summary on the status of activities in hypersonic aerodynamics at The Ohio State University after the first year of support by a Hypersonic Training and Research Grant funded by the NASA, the Air Force OSR and the Navy ONR. The program now supports seven graduate students who are pursuing their degrees under a restructured curicullum which emphasizes the modern state of hypersonic aerodynamics. They participate in a research program which includes a variety of experimental activities.

Air traffic control operational errors (less than established separation maintained) have been determined to be caused by human error in over ninety percent of reported incidents. This is reflected in numerous operational error analyses conducted quarterly by the FAA. “Cockpit Resource Management,” “Crew Coordination,” and “Professional Competence,” are all names of training being given to aircrews to heighten clear communications, group problem solving, the sharing of overlapping responsibility, and the initiative to maintain one another's situational awareness. The above named training programs all look into the role of human behavioral factors and crew coordination in flight deck operations. The Air Traffic Control System parallels these team dynamics and by emphasizing all aspects of human behavioral factors in ATC training, safety and efficiency of the air traffic system can be enhanced. Air Traffic Controller Awareness and Resource Training is intended to assist in that endeavor.

Terrain following/terrain avoidance/threat avoidance/obstacle avoidance [TF/(TA)2/OA] is an inescapable penetration technology for future aircraft. Properly implemented low altitude tactics will increase survivability given the current dense and mobile threat environment. Numerous functional elements, computationally intense algorithms, flight safety considerations, and pilot acceptance characterize this system. These system integration issues demand that a real-time engineering simulation be exercised before aircraft implementation. This paper describes an initial terrain following/terrain avoidance (TF/TA) simulation which blends aggressive trajectory generation, control coupling for trajectory tracking, map navigation, and aircraft and flight control system dynamic elements. Functional partitioning between simulation computers, timing requirements, information flow and requirements for intercomputer communication, interface software and data transfer requirements are also described.

Software has become a major portion of the products developed by Avionics Group, Rockwell International. As such, the need to develop software in a cost effective and productive manner is of increasing importance. The Avionics Group Software Engineering Training Program (SETP) was developed in response to the need to increase our personnel's knowledge of software engineering, particularly with respect to real-time, embedded systems development. This paper describes some of the highlights of the efforts to design and implement the SETP. Program definition, curriculum development, and implementation concerns are discussed.

This paper describes a software program, TestGen, that assists in the testing both of executable Ada code as well as assisting in the testing of high level descriptions of Ada designs using Ada/PDL pseudo-code. The TestGen program provides three distinct capabilities: 1. The Design Review Expert Assistant- Allows Ada designs to be thoroughly reviewed, insuring that all paths have been evaluated, and that alt possibilities have been covered. 2. The Unit Test Strategy Generator- Assists in the definition of unit test procedures using a “white box” testing technique. 3. The Test Coverage Analyzer- Determines the extent of coverage (the percentage of the total numbers of paths, branches and statements that were actually executed during a given test sequence). The TestGen tool is one of the AISLE (Ada/ADADL Integrated Software Lifecycle Environment) toolset, an integrated set of tools that assist the developers of Ada software through the development lifecycle.

The paper traces the development of fuel high temperature testing since its inception. Specification control tests are emphasized and the reasons for these tests and their operating conditions are given. Both proposed and accepted test methods are examined. Continuing problems with the precision and relevance of these tests are explored and the author's opinions on possible resolutions of these problems are given.

Earlier research performed by Shell Research sought to compare the performance of fuels in the Jet Fuel Thermal Oxidation Tester (JFTOT) with that in a simulated engine oil cooler. However the agreement between the rigs was poor and initial attempts to improve the correlation by modifying various JFTOT operating parameters were ineffective. Now, those same operating parameters have been readdressed in more detail, in order to determine the physical and chemical factors which control fuel response in the JFTOT. Flowrate experiments and activation energy measurements have indicated not only that the JFTOT's response to a fuel depends on the relative roles of chemical reaction and physical transport, but more significantly, the contribution of the two effects is fuel dependent.

Of particular concern to most spacecraft programs is the verification of the finite element model used to predict launch loads. The verification process requires a test-to-model correlation of the high loads producing modes. Presently, this usually requires building/using a test fixture to simulate the spacecraft-booster interface fixity conditions. This method, usually referred to as fixed-base modal testing, introduces significant uncertainties to the test results in the form of test stand flexibility, friction at the interface, etc. To avoid this myriad of problems and possibly reduce the overall structural test program duration significantly, alternative test programs have been developed. These test programs couple a standard modal test of a freely suspended structure with modified modal tests designed to highlight the character of the payload-booster interface without the need of simultaneously constraining all the interface degrees of freedom (DOF's).

A cross modal assurance criteria which represents the degree of correlation between the analytical modes and the test modes is defined. It is used as an indicator to predict the quality of the orthogonality with respect to the dynamically or statically reduced mass matrix using test modes. The root mean square values of the cross modal assurance criteria can be used to identify whether the significant errors exist in the analytical model or the test data.

Mathematical models of structures are validated by adjusting them to match the results of static and dynamic tests. Several automated methods have been developed to aid in the test-analysis correlation process. A recent method uses design sensitivity and optimization methods to directly adjust the Finite element model. The strengths and weaknesses of this method are demonstrated by the test-analysis correlation results from several modal surveys.

This paper contains a review of the program in Hypersonics currently being carried out at the State University of New York at Buffalo (SUNY/Buffalo) in collaboration with the Calspan-UB Research Center (CUBRC). A description is given of the academic features of the program (Courses, seminars, student-selection process) and the research activities.

Hypersonic Aerodynamics has attracted outstanding graduate students and faculty at NCSU. It has grown to 6 faculty and 32 graduate students for fall, 1988. A significant feature of the program is that students and faculty spend time at government laboratories which currently include NASA Langley Research Center, Naval Surface Warfare Center at Silver Spring, and the Wright Aeronautical Laboratories. Research projects include analysis, computational and experimental aerodynamics. The combined program produces graduates with the background needed to perform aerodynamics investigations of hypersonic aircraft and spacecraft. The research performed helps advance the state of the art as well as assist government laboratories in meeting their goals.

Structural nonlinearities should be considered in the analysis and modeling of mechanical systems for accuracy in predicting dynamic behavior. Moreover, checks for nonlinearity should address the type and class of nonlinearity in the structure and identify the probable cause. A series of experimental modal survey tests were carried out to determine and characterize the structural nonlinearities of the Space shuttle Main Engine (SSME) main injector. Different excitation regimes at various amplitudes were utilized to induce vibration and strain, and acceleration measurements were taken at judiciously selected locations. The test results indicated that both stiffness and damping non-linearities were present.

At some future time, on orbit repairs will have to be made to Space Station parts that become damaged, or otherwise lose their functional capabilities. This paper is a summary of the extensive study Grumman performed to define sources of structural and mechanical damage, define tools and fabrication processes for repair, implement prototype tool development, design and construct a mock-up of a Maintenance Work Station (MWS), and perform repairs under simulated “zero G” conditions. This study program confirmed the premise that repairs must and can be made by Astronauts while in an orbital environment. Since the program only began to investigate and solve the engineering problems of performing repairs in a space environment, adequate planning for engineering design and development is required to provide safe and continued operation of the Space Station.

This paper addresses the development of new planning methodologies which will evolve to successfully serve the Space Station Freedom program for many years to come. These planning processes will focus on the complex task of effectively managing the resources provided by the Space Station Freedom. These resources will be made available to the diverse International community of space station users in support of their ongoing investigative activities. These resources will also meet the needs associated with the growth and maintenance of the Space Station Freedom itself.

Currently there is a need for strategic planning/mission management techniques that help to reduce pilot workload and enhance decision making. This need is clearly seen in rotorcraft operations, especially during NOE flight in adverse conditions. To date, decision aiding techniques have focused on the development of avionics. However, another adjunct possibility is the development of formalized training programs that help a pilot to make quick, accurate decisions under time pressure. Although formalized training exists (e.g., Line Oriented Flight Training) there has been a dearth of literature that investigates the efficacy of the decision aiding strategies and tactics that these techniques employ. One such technique is contingency planning. The present study explored the relationship of contingency planning to safety and decision performance in air transport crews.