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This is the Engineering Test Report, SARR, SARP, DCS Receivers, Link Frequencies EMI Sensitive Band Test Results, AMSU-A2, S/N 107, for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A).
This is the Engineering Test Report, Radiated Emissions and SARR, SARP, DCS Receivers, Link Frequencies EMI Sensitive Band Test Results, AMSU-A1 SIN 108, for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A).
This is the Engineering Test Report, Radiated Emissions and SARR, SARP, DCS Receivers, Link Frequencies EMI Sensitive Band Test Results, AMSU-A1, S/N 109, for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A).
This is the Engineering Test Report, Radiated Emissions and SARR, SARP, DCS Receivers, Link Frequencies EMI Sensitive Band Test Results, AMSU-A2, S/N 108, for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A).
In a major cooperative program between U.S. Government agencies (represented by the U.S. Army Aeroflightdynamics Directorate and NASA Ames and Langley Research Centers) and United Technologies Corp., a 1/6 geometrically and aeroelastically scaled UTC model helicopter rotor was tested in the open-jet anechoic test section of the Duits-Nederlandse Windtunnel in the Netherlands. As the fourth entry under the Aerodynamic and Acoustic Testing of Model Rotors Program, several comprehensive acoustic and aerodynamic databases were obtained relating the important aerodynamic phenomena to both the near- and far-field acoustic radiation. In particular, high speed impulsive noise and blade-vortex interaction are of primary interest. This paper provides an initial summary of the acoustic measurements acquired for some of the different configurations tested. A review of the baseline swept tip rotor acoustic characteristics in the regimes of high speed forward flight, where high speed impulsive noise dominates, and low speed descent, where severe blade vortex interaction noise occurs, is presented. The trends of these primary noise sources are studied as the first step in validating the data for release and application.
This is the Engineering Test Report, AMSU-AL METSAT Instrument (S/N 105) Qualification Level Vibration Tests of December 1998 (S/0 605445, OC-419), for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A).
The United States space policy is evolving toward missions beyond low Earth orbit. In an effort to meet that policy, NASA has recognized Autonomous Mission Operations (AMO) as a valuable capability. Identified within AMO capabilities is the potential for autonomous planning and replanning during human spaceflight operations. That is allowing crew members to collectively or individually participate in the development of their own schedules. Currently, dedicated mission operations planners collaborate with international partners to create daily plans for astronauts aboard the International Space Station (ISS), taking into account mission requirements, ground rules, and various vehicle and payload constraints. In future deep space operations the crew will require more independence from ground support due to communication transmission delays. Furthermore, crew members who are provided with the capability to schedule their own activities are able to leverage direct experience operating in the space environment, and possibly maximize their efficiency. CAST (Crew Autonomous Scheduling Test) is an ISS investigation designed to analyze three important hypotheses about crew autonomous scheduling. First, given appropriate inputs, the crew is able to create and execute a plan in a reasonable period of time without impacts to mission success. Second, the proximity of the planner, in this case the crew, to the planned operations increases their operational efficiency. Third, crew members are more satisfied when given a role in plan development. This paper presents the results from a single astronaut test subject who participated in five CAST sessions. The details on the operational philosophy of CAST are discussed, including the approach to crew training, selection criteria for test days, and data collection methods. CAST is a technology demonstration payload sponsored by the ISS Research Science and Technology Office, and performed by experts in Mission Operations Planning from the Flight Operations Directorate at NASA Johnson Space Center, and researchers across multiple NASA centers. It is hoped the results of this investigation will guide NASA's implementation of autonomous mission operations for long duration human space missions to Mars and beyond.
Described herein is a comprehensive project—a large-scale test of an integrated refrigeration and storage system called the Ground Operations and Demonstration Unit for Liquid Hydrogen (GODU LH2), sponsored by the Advanced Exploration Systems Program and constructed at Kennedy Space Center. A commercial cryogenic refrigerator interfaced with a 125,000 liter liquid hydrogen tank and auxiliary systems in a manner that enabled control of the propellant state by extracting heat via a closed loop Brayton cycle refrigerator coupled to a novel internal heat exchanger. Three primary objectives were demonstrating zero-loss storage and transfer, gaseous liquefaction, and propellant densification. Testing was performed at three different liquid hydrogen fill-levels. Data were collected on tank pressure, internal tank temperature profiles, mass flow in and out of the system, and refrigeration system performance. All test objectives were successfully achieved during approximately two years of testing. A summary of the final results is presented in this paper.
A method is discussed developed to verify commercial printed-circuit boards for a shuttle orbital flight. The Space Acceleration Measurement System Project used this method first with great success. The test sequence is based on early fault detection, desire to test the final assembly, and integration with other verification testing. A component thermal screening test is performed first to force flaws in design, workmanship, parts, processes, and materials into observable failures. Then temperature definition tests are performed that consist of infrared scanning, thermal vacuum testing, and preliminary thermal operational testing. Only the engineering unit is used for temperature definition testing, but the preliminary thermal operational testing is performed on the flight unit after the temperature range has been defined. In the sequence of testing, vibration testing is performed next, but most vibration failures cannot be detected without subsequent temperature cycling. Finally, final assembly testing is performed to simulate the shuttle flight. An abbreviated thermal screening test is performed as a check after the vibration test, and then a complete thermal operational test is performed. The final assembly test finishes up with a burn-in of 100 hours of trouble-free operation. Verification is successful when all components and final assemblies have passed each test satisfactory. This method was very successful in verifying that commercial printed-circuit boards will survive in the shuttle environment.
This is the Engineering Test Report, AMSU-A2 METSAT Instrument (S/N 108) Acceptance Level Vibration Test of Dec 1999/Jan 2000 (S/O 784077, OC-454), for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A).
Currently on the International Space Station s (ISS) U.S. Segment, carbon dioxide (CO2) scrubbed from the cabin by a 4-Bed Molecular Sieve (4BMS) Carbon Dioxide Removal Assembly (CDRA) is vented overboard as a waste product. Likewise, the product hydrogen (H2) that will be generated by the Oxygen Generation Assembly (OGA) planned for installation will also be vented. A flight experiment has been proposed that will take the waste CO2 removed from the cabin, and via the catalytic Sabatier process, reduce it with waste H2 to generate water and methane. The water produced may provide cost and logistics savings for ISS by reducing the amount of water periodically re-supplied to orbit. To make this concept viable, a mechanical piston compressor and accumulator were developed for collecting and storing the CO2 from the CDRA. The compressor, accumulator and Sabatier system would be packaged together as one unit and referred to as the Carbon Dioxide Reduction Assembly (CRA). Testing was required to evaluate the performance of a 4BMS CDRA, compressor, accumulator, and Sabatier performance along with their operating rules when integrated together. This had been numerically modeled and simulated; however, testing was necessary to verify the results from the engineering analyses. Testing also allowed a better understanding of the practical inefficiencies and control issues involved in a fully integrated system versus the theoretical ideals in the model. This paper presents and discusses the results of an integrated engineering development unit test.
This paper describes the design, fabrication, and dynamic testing of a V-groove radiator development unit. The intended goal was to survive the dynamic environment of the Mars Observer mission. The development unit was designed to achieve a temperature of 80 K with a heat load of about 80 milliwatts. An analysis was performed to predict the thermal performance of the development unit. The radiator with a mass mockup of a Gamma Ray Spectrometer detector, the most massive of the candidate Mars Observer instrument detectors (1.7 Kg), passed vibration and acoustic testing to the Mars Observer requirements in effect at that time.
Fatigue test review on acoustic fatigue, plastic deformation, structural fatigue, supersonic transport materials, crack propagation and detection
Design and tests of water vapor electrolysis cell for generating and regulating spacecraft oxygen and for controlling humidity
Monitoring the Total Organic Carbon (TOC) in spacecraft potable water will be of major importance in long-duration human space exploration. In-flight analysis of potable water produced from a regenerative water processor provides immediate feedback on the quality of reclaimed water for crew health as well as water processing system health monitoring. This paper updates the progress in development of the next generation Total Organic Carbon Analyzer (TOCA) designed for the unique requirements of an exploration-class mission. The current objective is to design, build, certify, deliver, and operate a TOCA technology demonstration on the International Space Station (ISS). The next generation analyzer system technology was previously developed and selected among a feasibility study of other options. The new system provides primary advantages of reduced mass and volume through reduced system complexity and reduced need for consumables; therefore, the flight project is named MiniTOCA. The project has recently completed design of the tech demo instrument and assembled and tested a flight-like engineering development unit. The engineering unit has undergone performance testing and environmental testing which provides confidence for the project to move forward with flight unit production and certification activities. Test results are summarized in this paper. The flight unit is targeted for delivery to ISS in late 2025.
Monitoring the Total Organic Carbon (TOC) in spacecraft potable water will be of major importance in long-duration human space exploration. In-flight analysis of potable water produced from a regenerative water processor provides immediate feedback on the quality of reclaimed water for crew health as well as water processing system health monitoring. This paper updates the progress in development of the next generation Total Organic Carbon Analyzer (TOCA) designed for the unique requirements of an exploration-class mission. The current objective is to design, build, certify, deliver, and operate a TOCA technology demonstration on the International Space Station (ISS). The next generation analyzer system technology was previously developed and selected among a feasibility study of other options. The new system provides primary advantages of reduced mass and volume through reduced system complexity and reduced need for consumables; therefore, the flight project is named MiniTOCA. The project has recently completed design of the tech demo instrument and assembled and tested a flight-like engineering development unit. The engineering unit has undergone performance testing and environmental testing which provides confidence for the project to move forward with flight unit production and certification activities. Test results are summarized in this paper. The flight unit is targeted for delivery to ISS in late 2025.
Laminar boundary layer velocity measurements are made on a 10-degree half-angle wedge in a Mach 10 flow. Two types of discrete boundary layer trips were used to perturb the boundary layer gas. The first was a 2-mm tall, 4-mm diameter cylindrical trip. The second was a scaled version of the Orbiter Boundary Layer Transition (BLT) Detailed Test Objective (DTO) trip. Both 1-mm and 2.5-mm tall BLT DTO trips were tested. Additionally, side-view and plan-view axial boundary layer velocity measurements were made in the absence of these tripping devices. The free-stream unit Reynolds numbers tested for the cylindrical trips were 1.7x10(exp 6)/m and 3.3x10(exp 6)/m. The free-stream unit Reynolds number tested for the BLT DTO trips was 1.7x10(exp 6)/m. The angle of attack was kept at approximately 5-degrees for most of the tests resulting in a Mach number of approximately 8.3. These combinations of unit Reynolds numbers and angle of attack resulted in laminar flowfields. To study the precision of the measurement technique, the angle of attack was varied during one run. Nitric-oxide (NO) molecular tagging velocimetry (MTV) was used to obtain averaged axial velocity values and associated uncertainties. These uncertainties are as low as 20 m/s. An interline, progressive scan CCD camera was used to obtain separate images of the initial reference and shifted NO molecules that had been tagged by the laser. The CCD configuration allowed for sub-microsecond sequential acquisition of both images. The maximum planar spatial resolution achieved for the side-view velocity measurements was 0.07-mm in the wall-normal direction by 1.45-mm in the streamwise direction with a spatial depth of 0.5-mm. For the plan-view measurements, the maximum planar spatial resolution in the spanwise and streamwise directions was 0.69-mm by 1.28-mm, respectively, with a spatial depth of 0.5-mm. Temperature sensitive paint (TSP) measurements are provided to compliment the velocity data and to provide further insight into the behavior of the boundary layers. The experiments were performed at the NASA Langley Research Center 31-Inch Mach 10 Air tunnel.
During random vibration testing of electronic boxes there is often a desire to know the dynamic response of certain internal printed wiring boards (PWBs) for the purpose of monitoring the response of sensitive hardware or for post-test forensic analysis in support of anomaly investigation. Due to restrictions on internally mounted accelerometers for most flight hardware there is usually no means to empirically observe the internal dynamics of the unit, so one must resort to crude and highly uncertain approximations. One common practice is to apply Miles Equation, which does not account for the coupled response of the board in the chassis, resulting in significant over- or under-prediction. This paper explores the application of simple multiple-degree-of-freedom lumped parameter modeling to predict the coupled random vibration response of the PWBs in their fundamental modes of vibration. A simple tool using this approach could be used during or following a random vibration test to interpret vibration test data from a single external chassis measurement to deduce internal board dynamics by means of a rapid correlation analysis. Such a tool might also be useful in early design stages as a supplemental analysis to a more detailed finite element analysis to quickly prototype and analyze the dynamics of various design iterations. After developing the theoretical basis, a lumped parameter modeling approach is applied to an electronic unit for which both external and internal test vibration response measurements are available for direct comparison. Reasonable correlation of the results demonstrates the potential viability of such an approach. Further development of the preliminary approach presented in this paper will involve correlation with detailed finite element models and additional relevant test data.