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At least 217 records · Page 12

UH-60A Airloads Flight Test Program: Data Counter 9505

The data collection portion of the UH-60A Airloads Flight Test Program (ref. 1) was conducted between July 1993 and February 1994. At the time, the UH-60A Airloads Program was the most comprehensive and data-rich rotorcraft flight test program that NASA and the U.S. Army had ever attempted. It was part of the Modern Technology Rotors Program (ref. 2), where several different rotors were tested in small- and full-scale wind tunnels combined with flight testing. The UH-60A portion of this program allowed for comparison between other tests performed and served as a scientific quality database for validating current and new computational and simulation models. The UH-60A flight test data was stored in a comprehensive, easily accessed database known as the Tilt Rotor Engineering Database System, or TRENDS (ref. 3). With over 30 years of rotor testing experience (ref. 4), NASA and the Army’s goal of the Airloads Flight Test Program was to collect data for a wide range of operating conditions, and to provide an extensive amount of data to improve the understanding of rotors and validate and improve prediction codes. This report presents the entire archived data set from Counter 9505 (Run 95, point 5) from the UH-60A Airloads Flight Test Program. There were 1,078 total data set counters acquired and archived during 57 accumulated flight hours and 31 research flights. Over 900 counters were research flight data acquisition data points. Counter 9505 is a low altitude, moderate airspeed, level-flight test condition. Ground acoustic microphone data was acquired for this counter but the acoustic data is not included in this report.

Kufeld, Robert M.↗

Investigation of a Helicopter Individual Blade Control (IBC) System in Two Full-Scale Wind Tunnel Tests: Volume I

This report presents the data acquired during the testing of an individual blade control (IBC) system on a full-scale helicopter rotor in two test entries in the NASA Ames 40- by 80-Foot Wind Tunnel. The objective of these investigations was to evaluate the potential benefits of using IBC to improve rotor performance, reduce blade vortex interaction (BVI) noise, and alleviate helicopter vibrations. The wind tunnel tests were an international, collaborative effort between NASA, the U.S. Army Aeroflightdynamics Directorate, ZF Luftfahrttechnik GmbH, Eurocopter Deutschland GmbH, and the German Aerospace Laboratory (DLR). They were conducted as a task of the U.S./German Memorandum of Understanding (MOU) on Helicopter Aeromechanics. The IBC tests were performed using a full-scale BO-105 helicopter rotor mounted to the NASA/U.S. Army Rotor Test Apparatus (RTA). The first test, performed in 1993, was the first full-scale wind tunnel test to explore the effects of an IBC system on rotor vibration, noise, and performance. In this test, the pitch links of the rotor were replaced by servo-actuators. The servo-actuators and IBC control system were designed and manufactured by ZF Luftfahrttechnik GmbH. This control system allowed the pitch of each rotor blade to be changed independently of the other blades. The IBC inputs had large effects on the hub vibrations and BVI noise. However, the rotor hub moments were not retrimmed with each new IBC input. This resulted in an out-of-trim rotor configuration. The same IBC system was used in the second IBC test performed in 1994. This test more carefully investigated the potential of IBC to simultaneously reduce noise and vibration and also investigated the effect of IBC on rotor performance in high-speed-cruise flight. In the 1994 test, the hub moment and rotor thrust were readjusted to maintain rotor trim as the IBC inputs were applied. For this reason, the data taken from the second test are considered to be more accurate, except for some unique IBC input combinations not repeated in the second test. IBC controls that were evaluated were single-frequency inputs from 2/rev to 6/rev and multi-harmonic combinations of these frequencies to form pulses, wavelets, and doublets. Extensive data were acquired for each IBC data point. These data included rotor performance, average and time-varying hub loads, rotor blade bending loads, control system loads, inboard and outboard blade pitch motions, and BVI noise data. The rotor balance hub force and moment data included the mean values, half-peak-to-peak values, and sine/cosine harmonics up to the 20th rotor harmonic. The time history and averaged Fourier spectrum for each measurement are available electronically from NASA Ames Research Center. The data indicate that significant reduction in both BVI noise and hub vibration can be obtained using IBC. The 2/rev input produced the best single-frequency results. At a typical descent flight condition, 2/rev IBC combined with other IBC harmonics reduced the BVI noise up to 12 dB (85 percent) at some microphone locations. At the same time, this input could also reduce the dominant 4/rev vibratory hub loads by up to 75 percent. The data also show that performance improvements of up to 7 percent were obtained using 2/rev IBC at high-speed forward flight conditions. An analysis of the hydraulic power requirements for BVI noise suppression, vibration reduction, and rotor performance improvement is included in this report. This analysis shows that the power required by the IBC system is negligible at low-speed flight conditions, and that a net gain of 3 percent of rotor horsepower can be achieved at high-speed flight conditions.

Investigation↗

Corps battle simulation

CBS is a computerize battle simulation system driven by Army Corps and Division Command Post Exercises and Battle Command Training Program War Fighter exercises.

simulation training Army↗

Proceedings on the Working Group on Extraterrestrial Resources - Fourth annual meeting

The Working Group on Extraterrestrial Resources is composed of people from the National Aeronautics and Space Administration (NASA), the U. S. Air Force, the U. S. Navy, Office of Engineers of the U. S. Army, U S. Geological Survey, the Department of Agriculture, and the Rand Corporation. It was organized for the following function: "To evaluate the feasibility and usefulness of the employment of extraterrestrial resources with the objective of reducing dependence of lunar and planetary exploration on terrestrial supplies; to advise cognizant agencies on requirements pertinent to these objectives, and to point out the implications affecting these goals. "

EXTRATERRESTRIAL ENVIRONMENT↗

Apollo Program Management, Kennedy Space Center, Florida

The evolution of the Kennedy Space Center as the launch organization for Apollo/ Saturn V involved the concurrent solution of numerous complex problems. A significant increase in manpower was involved. Large and complex checkout and launch facilities were to be designed and constructed. Expansion of operational capabilities required the establishment and integration of a Government-Contractor operational team. From an initial cadre of approximately 200 civil service personnel of the Army Ballistic Missile Agency, transferred to NASA in 1960 following its establishment, expansion to the present civil service level of 2,900 occurred in the last seven years. Established within NASA as a directorate of the Marshall Space Flight Center, KSC achieved center status in 1962. With its designation as a Center, KSC accomplished the development and staffing of an organization that could perform procurement, resources, financial, and other management requirements formerly provided by the parent organization. In addition to continuing launch operations for established programs, KSC undertook the design and construction of large, new, and unique launch facilities for Apollo/Saturn V. With the expansion of the civil service work force, KSC integrated contractor organizations employing 23,000 personnel at the Center to perform specific operational and support missions under the technical supervision and observation of the Government team. The management techniques, organizational concepts, and continuing efforts utilized to meet the Apollo goals and challenges are discussed in this document.

Source record↗

Pilot reports of disorientation across 14 years of flight.

The purpose of this study was to compare recent incidents involving disorientation in flight reported by 336 Air Force, Army, and Navy pilots with incidents reported by 137 pilots in 1956. The pilots reported their experiences using a check list and a written description of an experience with disorientation in the aircraft they were flying at the time. The latter included 40 incidents which occurred in support of operations in Vietnam. The reports of disorientation showed a striking similarity across types of aircraft flown over 14 years of flying, as well as with the incidents occurring in Vietnam. However, some variation in reports between aircraft types was noted. These reports of disorientation suggest that disorientation is currently experienced in a wide variety of flight operations and that it will continue to be experienced by aircraft pilots.

Clark, B.↗

Manual for 70 mm hand-held photography from Skylab

A manual and atlas used on the Skylab mission for hand-held photography are presented. The manual covers terrain, environmental, meteorological, and dim light photography while the atlas covers sections from the Army Map Service 1:40.000,000 world map, a glossary of geologic terms, geologic maps, and recommended exposure times.

Lowman, P. D., Jr.↗

The Earth Resources Program of the Corps of Engineers

The mission of the Corps of Engineers of the U.S. Army and the contributions made by the ERTS-1 data system are discussed. The use of satellite-borne sensors and aerial photography for projects involving engineering geology, flood control, master planning, and fluid dynamics and interations is reported. Examples of engineering projects are provided in the form of aerial photographs and multispectral band scanner imagery.

Jarman, J. W.↗

A technique for interpretation of multispectral remote sensor data

The author has identified the following significant results. The U.S. Army Engineer Waterways Experiment Station is engaged in a study to detect from ERTS-1 satellite data alterations to the absorption and scattering properties caused by movement of suspended particles and solutes in selected areas of the Chesapeake Bay and to correlate the data to determine the feasibility of delineating flow patterns, flushing action of the estuary, and sediment and pollutant dispersion. As a part of this study, ADP techniques have been developed that permit automatic interpretation of data from any multispectral remote sensor with computer systems which have limited memory capacity and computing speed. The multispectral remote sensor is considered as a reflectance spectrophotometer. The data which define the spectral reflectance characteristics of a scene are scanned pixel by pixel. Each pixel whose spectral reflectance matches a reference spectrum is identified, and the results are shown in a map that identifies the locations where spectrum matches were detected and spectrum that was matched. The interpretation technique is described and an example of interpreted data from ERTS-1 is presented.

Williamson, A. N.↗

Advancement of proprotor technology. Task 2: Wind-tunnel test results

An advanced-design 25-foot-diameter flightworthy proprotor was tested in the NASA-Ames Large-Scale Wind Tunnel. These tests, have verified and confirmed the theory and design solutions developed as part of the Army Composite Aircraft Program. This report presents the test results and compares them with theoretical predictions. During performance tests, the results met or exceeded predictions. Hover thrust 15 percent greater than the predicted maximum was measured. In airplane mode, propulsive efficiencies (some of which exceeded 90 percent) agreed with theory.

Source record↗

Summary of atmospheric data observations for 155 flight of MSFC/ABMA related aerospace vehicles

A summary of selected atmospheric conditions observed near launch time for 155 NASA-Marshall Space Flight Center and Army Ballistic Missile Agency related vehicles, launched primarilv from Cape Kennedy, Florida, between August 20, 1953, and November 16, 1963, is presented. Values of ambient pressure, temperature, relative humidity, ground winds, visual observations, density aloft, and wind/wind shear aloft are included. The extremes of these parameters are listed for each type of launch vehicle.

Johnson, D. L.↗

Government-Industry Data Exchange Program (GIDEP)

The Government-Industry Data Exchange Program (GIDEP) was originated in 1959 by the Army, Navy, and Air Force Ballistic Missile Agencies. Known at that time as IDEP--Interservice Data Exchange Program--its intent was to eliminate duplicate testing of parts and components by disseminating pertinent test data among Department of Defense contractors and various government agencies. In 1966 both the National Aeronautics and Space Administration and the Canadian Military Electronics Standards Agency (CAMESA) recognized the value of the data provided by the program and became participants. Today, GIDEP provides the interchange of specialized technical data to all the military services, participating government contractors and numerous government agencies such as the Atomic Energy Commission, Federal Aviation Administration, Defense Supply Agency, and the Small Business Administration.

Richards, E. T.↗

ERTS-1 flood hazard studies in the Mississippi River Basin

The Spring 1973 Mississippi River flood was investigated using remotely sensed data from ERTS-1. Both manual and automatic analyses of the data indicate that ERTS-1 is extremely useful as a regional tool for flood and floodplain management. The maximum error of such flood area measurements is conservatively estimated to be less than five percent. Change detection analysis indicates that the flood had major impacts on soil moisture, land pattern stability, and vegetation stress. Flood hazard identification was conducted using photointerpretation techniques in three study areas along the Mississippi River using pre-flood ERTS-1 imagery down to 1:100,000 scale. Flood prone area boundaries obtained from ERTS-1 were generally in agreement with flood hazard maps produced by the U.S. Army Corps of Engineers and the U.S. Geological Survey although the latter are somewhat more detailed because of their larger scale. Initial results indicate that ERTS-1 digital mapping of the flood-prone areas can be performed at least 1:62,500 which is comparable to conventional flood hazard map scales.

Rango, A.↗

Operating manual for coaxial injection combustion model

An operating manual for the coaxial injection combustion model (CICM) is presented as the final report for an eleven month effort designed to provide improvement, to verify, and to document the comprehensive computer program for analyzing the performance of thrust chamber operation with gas/liquid coaxial jet injection. The effort culminated in delivery of an operation FORTRAN IV computer program and associated documentation pertaining to the combustion conditions in the space shuttle main engine. The computer program is structured for compatibility with the standardized Joint Army-Navy-NASA-Air Force (JANNAF) performance evaluation procedure. Use of the CICM in conjunction with the JANNAF procedure allows the analysis of engine systems using coaxial gas/liquid injection.

Sutton, R. D.↗

The Saturn management concept

Management of the Saturn launch vehicles was an evolutionary process, requiring constant interaction between NASA Headquarters, the Marshall Space Flight Center (particularly the Saturn 5 Program Office), and the various prime contractors. Successful Saturn management was a blend of the decades of experience of the von Braun team, management concepts from the Army, Navy, Air Force, and Government, and private industry. The Saturn 5 Program Office shared a unique relationship with the Apollo Program Office at NASA Headquarters. Much of the success of the Saturn 5 Program Office was based on its painstaking attention to detail, emphasis on individual responsibilities (backed up by comprehensive program element plans and management matrices), and a high degree of visibility as embodied in the Program Control Center.

Bilstein, R. E.↗