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A top level summary of activities conducted throughout the course of the EDOMP in response to initial concerns at the outset of the program is provided. Significant findings from the investigations are summarized, together with resulting countermeasures that were implemented and flight rules that were developed in response to these findings. Subsequent paragraphs provide more information; details will be found in the referenced sections.
Mental workload can be de.ned as the ratio of demand to allocated resources. Multiple-resource theory stresses the importance of distribution of tasks and information across various human sensory channels to reduce mental workload. One sensory channel that has been of interest since the late 1800s is touch. Unlike the more typical displays that target vision or hearing, tactile displays present information to the user s sense of touch. We present a summary of different methods for tactile display, historic and more recent systems that incorporate tactile display for information presentation, advantages and disadvantages of targeting the tactile channel, and future directions in tactile display research.
A summary has been made of available data on the characteristics of airfoil sections with trailing-edge high-lift devices. Data for plain, split, and slotted flaps are collected and analyzed. The effects of each of the variables involved in the design of the various types of flap are examined and, in cases where sufficient data are given, optimum configurations are deduced. Wherever possible, the effects of airfoil section, Reynolds number, and leading-edge roughness are shown. For single and double slotted flaps, where a great mass of unrelated date are available, maximum lift coefficients of a large number of configurations are presented in tables.
During the 113 missions of the Space Transportation System (STS), the Space Shuffle fleet has been exposed to the elements on the launch pad for a total of 4195 days. The Natural Environments Branch at Marshall Space Flight Center archives atmospheric environments to which the Space Shuttle vehicles are exposed. This paper provides a summary of the historical record of the meteorological conditions encountered by the Space Shuttle fleet during the pad exposure period. Sources of the surface parameters, including temperature, dew point temperature, relative humidity, wind speed, wind direction, sea level pressure and precipitation are presented. Data is provided from the first launch of the STS in 1981 through the launch of STS-107 in 2003.
The Morphing Project at the National Aeronautics and Space Agency s (NASA) Langley Research Center (LaRC) is part of the Breakthrough Vehicle Technologies Project, Vehicle Systems Program that conducts fundamental research on advanced technologies for future flight vehicles. The objectives of the Morphing Project are to develop and assess the advanced technologies and integrated component concepts to enable efficient, multi-point adaptability of flight vehicles; primarily through the application of adaptive structures and adaptive flow control to substantially alter vehicle performance characteristics. This document is a compilation of research summaries and other information on the project for fiscal year 2002. The focus is to provide a brief overview of the project content, technical results and lessons learned. At the time of publication, the Vehicle Systems Program (which includes the Morphing Project) is undergoing a program re-planning and reorganization. Accordingly, the programmatic descriptions of this document pertain only to the program as of fiscal year 2002.
Mental workload can be defined as the ratio of demand to allocated resources. Multiple- resource theory stresses the importance of distribution of tasks and information across various sensory channels of the human to reduce mental workload. One sensory channel that has been of interest since the late 1800s is touch. Unlike the more typical displays that target vision or hearing, tactile displays present information to the user s sense of touch. We present a summary of different methods for tactile display; historic and more recent systems that incorporate tactile display for information presentation; advantages and disadvantages of targeting the tactile channel; and future directions in tactile display research.
This report summarizes research conducted on an aircraft based Runway Incursion Advisory and Alerting System (RIAAS) developed under a cooperative agreement between Rannoch Corporation and the NASA Langley Research Center. A summary of RIAAS is presented along with results from simulation and flight testing, safety benefits, and key technical issues.
Several studies have concluded that a supersonic aircraft, if environmentally acceptable and economically viable, could successfully compete in the 21st century marketplace. However, before industry can commit to what is estimated as a 15 to 20 billion dollar investment, several barrier issues must be resolved. In an effort to address these barrier issues, NASA and Industry teamed to form the High-Speed Research (HSR) program. As part of this program, the Critical Propulsion Components (CPC) element was created and assigned the task of developing those propulsion component technologies necessary to: (1) reduce cruise emissions by a factor of 10 and (2) meet the ever-increasing airport noise restrictions with an economically viable propulsion system. The CPC-identified critical components were ultra-low emission combustors, low-noise/high-performance exhaust nozzles, low-noise fans, and stable/high-performance inlets. Propulsion cycle studies (coordinated with NASA Langley Research Center sponsored airplane studies) were conducted throughout this CPC program to help evaluate candidate components and select the best concepts for the more complex and larger scale research efforts. The propulsion cycle and components ultimately selected were a mixed-flow turbofan (MFTF) engine employing a lean, premixed, prevaporized (LPP) combustor coupled to a two-dimensional mixed compression inlet and a two-dimensional mixer/ejector nozzle. Due to the large amount of material presented in this report, it was prepared in four volumes; Volume 1: Summary, Introduction, and Propulsion System Studies, Volume 2: Combustor, Volume 3: Exhaust Nozzle, and Volume 4: Inlet and Fan/ Inlet Acoustic Team.
In response to the Vision, NASA commissioned strategic and capability roadmap teams to develop the pathways for turning the Vision into a reality. The strategic roadmaps were derived from the Vision for Space Exploration and the Aldrich Commission Report dated June 2004. NASA identified 12 strategic areas for roadmapping. The Agency added a thirteenth area on nuclear systems because the topic affects the entire program portfolio. To ensure long-term public visibility and engagement, NASA established a committee for each of the 13 areas. These committees - made up of prominent members of the scientific and aerospace industry communities and senior government personnel - worked under the Federal Advisory Committee Act. A committee was formed for each of the following program areas: 1) Robotic and Human Lunar Exploration; 2) Robotic and Human Exploration of Mars; 3) Solar System Exploration; 4) Search for Earth-Like Planets; 5) Exploration Transportation System; 6) International Space Station; 7) Space Shuttle; 8) Universe Exploration; 9) Earth Science and Applications from Space; 10) Sun-Solar System Connection; 11) Aeronautical Technologies; 12) Education; 13) Nuclear Systems. This document contains roadmap summaries for 10 of these 13 program areas; The International Space Station, Space Shuttle, and Education are excluded. The completed roadmaps for the following committees: Robotic and Human Exploration of Mars; Solar System Exploration; Search for Earth-Like Planets; Universe Exploration; Earth Science and Applications from Space; Sun-Solar System Connection are collected in a separate Strategic Roadmaps volume. This document contains memebership rosters and charters for all 13 committees.
This document is the result of eight months of hard work and dedication from NASA, industry, other government agencies, and academic experts from across the nation. It provides a summary of the capabilities necessary to execute the Vision for Space Exploration and the key architecture decisions that drive the direction for those capabilities. This report is being provided to the Exploration Systems Architecture Study (ESAS) team for consideration in development of an architecture approach and investment strategy to support NASA future mission, programs and budget requests. In addition, it will be an excellent reference for NASA's strategic planning. A more detailed set of roadmaps at the technology and sub-capability levels are available on CD. These detailed products include key driving assumptions, capability maturation assessments, and technology and capability development roadmaps.
The Core Complete Environmental Control and Life Support (ECLS) System for the International Space Station (ISS) will consist of components and subsystems in both the United States (U.S.) and International Partner elements which together will perform the functions of Temperature and Humidity Control (THC), Atmosphere Control and Supply (ACS), Atmosphere Revitalization (AR), Water Recovery and Management (WRM), Fire Detection and Suppression (FDS), and Vacuum System (VS) for the station. Due to limited resources available on ISS, detailed attention is given to minimizing and tracking all resources associated with all systems, beginning with estimates during the hardware development phase through measured actuals when flight hardware is built and delivered. A summary of resources consumed by the addition of future U.S. ECLS system hardware to get to Core Complete is presented, including launch weight, average continuous and peak power loads, on-orbit volume and resupply logistics.
We propose a summary product that describes data belonging to each one degree grid cell by a set of multivariate representatives and weights and errors associated with them.
This paper gives a data table summary of the different types of engineering sensors that are used onboard a typical spacecraft.
Experimental measurements of a generic tractor-trailer were obtained in two wind tunnels at Ames Research Center. After a preliminary study at atmospheric conditions in the 7- by 10-Foot Wind Tunnel, additional testing was conducted at Reynolds numbers corresponding to full-scale highway speeds in the 12-Foot Pressure Wind Tunnel. To facilitate computational modeling, the 1:8-scale geometry, designated the Generic Conventional Model, included a simplified underbody and omitted many small-scale details. The measurements included overall and component forces and moments, static and dynamic surface pressures, and three-component particle image velocimetry. This summary report highlights the effects of numerous drag reduction concepts and provides details of the model installation in both wind tunnels. To provide a basis for comparison, the wind-averaged drag coefficient was tabulated for all configurations tested. Relative to the baseline configuration representative of a modern class-8 tractor-trailer, the most effective concepts were the trailer base flaps and trailer belly box providing a drag-coefficient reduction of 0.0855 and 0.0494, respectively. Trailer side skirts were less effective yielding a drag reduction of 0.0260. The database of this experimental effort is publicly available for further analysis.
A viewgraph presentation describing the fundamental requirements and constraints necessary to begin the acquisition of an International Space Station commercial cargo service is presented. The topics include: 1) Background; 2) Philosophy; 3) Cargo Balance; 4) Cargo Types; 5) ICCS Flight Rate; 6) Late and Early Access; 7) Power to Payloads; 8) Mating Locatin Options; 9) ISS Docking and Berthing; 10) Vehicle Stay Time; 11) ISS Resource Availability; 12) Robotic and EVA Compatability; 13) Return Cargo; and 14) Key Requirements Summary.
Statistical jet noise prediction codes that accurately predict spectral directivity for both cold and hot jets are highly sought both in industry and academia. Their formulation, whether based upon manipulations of the Navier-Stokes equations or upon heuristic arguments, require substantial experimental observation of jet turbulence statistics. Unfortunately, the statistics of most interest involve the space-time correlation of flow quantities, especially velocity. Until the last 10 years, all turbulence statistics were made with single-point probes, such as hotwires or laser Doppler anemometry. Particle image velocimetry (PIV) brought many new insights with its ability to measure velocity fields over large regions of jets simultaneously; however, it could not measure velocity at rates higher than a few fields per second, making it unsuitable for obtaining temporal spectra and correlations. The development of time-resolved PIV, herein called TR-PIV, has removed this limitation, enabling measurement of velocity fields at high resolution in both space and time. In this paper, ground-breaking results from the application of TR-PIV to single-flow hot jets are used to explore the impact of heat on turbulent statistics of interest to jet noise models. First, a brief summary of validation studies is reported, undertaken to show that the new technique produces the same trusted results as hotwire at cold, low-speed jets. Second, velocity spectra from cold and hot jets are compared to see the effect of heat on the spectra. It is seen that heated jets possess 10 percent more turbulence intensity compared to the unheated jets with the same velocity. The spectral shapes, when normalized using Strouhal scaling, are insensitive to temperature if the stream-wise location is normalized relative to the potential core length. Similarly, second order velocity correlations, of interest in modeling of jet noise sources, are also insensitive to temperature as well.
The F-111 is a biservice, multimission, tactical aircraft being developed for the Air Force and Navy by General Dynamics and Grumman. The general arrangement of the F-111 is shown in figure 1. This aircraft, through the use of the "variable sweep wing" concept, offers the possibility of combining a wide range of mission capabilities into a single aircraft. The F-111 is a direct outgrowth of the Langley Research Center's variable sweep research which began in 1947. The early research culminated in the X-5 variable sweep research airplane which demonstrated the advantage and feasibility of in-flight sweep variation~ The X-5 utilized the translating wing concept to offset the longitudinal stability variation with sweep changes. Later Langley research beginning in 1958 resulted in the "outboard pivot" concept which eliminated the need for wing translation and led .to the TFX (F-111) concept. A chronology of the NACA/NASA variable sweep research effort and direct su~port of the TFX up to the awarding of the contract to General Dynamics/Grumman on November 24, 1962, is presented in refer'ence 1. Since the awarding of the contract, the Langley, Ames, Lewis, and Flight Research Centers have been actively supporting the F-111 development program. Because of the strong NASA interest in this aircraft and the large magnitude of NASA support involved, it was felt desirable to document this support. The purpose of this paper therefore is to present a brief summary of the NASA support, in chronological order, through December 1965, beginning with the awarding of the contract in November 1962.
A computational fluid dynamics (CFD) validation workshop for synthetic jets and turbulent separation control (CFDVAL2004) was held in Williamsburg, Virginia in March 2004. Three cases were investigated: synthetic jet into quiescent air, synthetic jet into a turbulent boundary layer crossflow, and flow over a hump model with no-flow-control, steady suction, and oscillatory control. This paper is a summary of the CFD results from the workshop. Although some detailed results are shown, mostly a broad viewpoint is taken, and the CFD state-of-the-art for predicting these types of flows is evaluated from a general point of view. Overall, for synthetic jets, CFD can only qualitatively predict the flow physics, but there is some uncertainty regarding how to best model the unsteady boundary conditions from the experiment consistently. As a result, there is wide variation among CFD results. For the hump flow, CFD as a whole is capable of predicting many of the particulars of this flow provided that tunnel blockage is accounted for, but the length of the separated region compared to experimental results is consistently overpredicted.