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Includes sound generation, transmission, and attenua-
Includes NASA appropriation hearings; aviation law;
CONTRACT OR GRANT
The second Control Of Flexible Structures Flight Experiment
VOLUME 27 NUMBER 21 / NOVEMBER 8, 1989
Scientific and Technical Aerospace Reports
A Semimonthly Publication of the National Aeronautics and Space Administration
01 AERONAUTICS (GENERAL)
Actual production costs are compared with estimated production costs predicted from the models to create measure of cost overruns and cost underruns. A set of factors that are associated with instances of cost over/underruns are identified. These factors reflect aspects of the aircraft program, the political and economic environment at the time of commencement of production on the aircraft program, and the financial condition of the prime contractor.
Includes aerodynamics of bodies, combinations, wings, rotors, and control surfaces; and internal flow ducts and turbomachinery
For related information see also 34 Fluid Mechanics and Heat Transfer.
N89-26807# Air Force Systems Command, Wright-Patterson AFB, OH. Foreign Technology Div. ACTA AERONAUTICA ET ASTRONAUTICA SINICA, VOLUME 8, NUMBER 12, DECEMBER 1987 (SELECTED ARTICLES) 15 Feb. 1989
Transl. into ENGLISH from Hangkong Xuebao (Peoples Republic of China), v. 8, no. 12, Dec. 1987 p 8557-8562, 8585-8593, and 8601-8610 (AD-A206782; FTD-ID(RS)T-0942-88) Avail: NTIS HC A04/MF A01 CSCL 01/2
Aircraft take off and landing gear are studied in order to understand nose wheel shimmy and provide measures to prevent it. It also deals with an analysis of runway dynamics and other such similar areas as nose wheel operation. Semi-Prepared Airfield and Design of Double-Action Shock Absorber: Airfields, in wars of the future, most necessarily suffer damage. To satisfy the peculiar demands of using this type of airfield, the design concepts of double action or double gas chamber shock shock absorbers. Moreover, as concerns their static and dynamic characteristics as well as the main parameters in the principles for their selection, it makes a relatively detailed comparative analysis. The settlement on standards for the unevenness of airfield runways, is based on the concept of power spectra. It introduces basic methods for measuring random variables from the unevenness of airfield runways. It drafts curves for the power spectra of uneven runways and carries out a preliminary analysis of the dynamic effects in aircraft ground surface taxing.
N89-26810*# National Aeronautics and Space Administration.
A wind tunnel test was conducted to evaluate the aerodynamic characteristics and wing pressure distributions of a variable wing sweep aircraft having wing panels that are modified to promote laminar flow. The modified wing section shapes were incorporated over most of the exposed outer wing panel span and were obtained by extending the leading edge and adding thickness to the existing wing upper surface forward of 60 percent chord. Two different wing configurations, one each for Mach numbers 0.7 and 0.8, were tested on the model simultaneously, with one wing configuration on the left side and the other on the right. The tests were conducted at Mach numbers 0.20 to 0.90 for wing sweep angles of 20, 25, 30, and 35 degrees. Longitudinal, lateral and directional aerodynamic characteristics of the modified and baseline configurations, and selected pressure distributions for the modified configurations, are presented in graphical form without analysis. A tabulation of the pressure data for the modified configuration is available as microfiche.
N89-26808* # National Aeronautics and Space Administration.
Presented at the International
Two sensor development programs being conducted at the Fluid Mechanics Laboratory, NASA Ames Research Center are described, one in progress and the other being initiated. The ongoing program involves digital image velocimetry for velocity field measurements of time-dependent flows. The new program involves advanced acoustic sensors for wind tunnel applications.
N89-26809# Naval Postgraduate School, Monterey, CA. Dept.
This study tests relationships between measures of the state-of-the-art of technology and advances in technology with production cost. The analysis is conducted using a sample of military aircraft. Parametric cost estimating models are developed.
N89-26811*# National Aeronautics and Space Administration.
Equations are derived for computing surface waves on smooth surfaces, including surfaces with a nonuniform wave speed. The prior literature dealt primarily with the theoretical development with little consideration given to computational methods, and examples were limited to waves on surfaces of simple analytic description, such as cones, spheres, and cylinders. The computational procedure presented is a relatively general method. Sample