ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • AIRCRAFT DESIGN, TESTING AND PERFORMANCE  (51)
  • 2015-2019
  • 1975-1979  (51)
  • 1950-1954
  • 1930-1934
  • 1925-1929
  • 1976  (51)
  • 1
    Publication Date: 2016-06-07
    Description: A linearized theory wing design and optimization procedure which allows physical realism and practical considerations to be imposed as constraints on the optimum (least drag due to lift) solution is discussed and examples of application are presented. In addition to the usual constraints on lift and pitching moment, constraints are imposed on wing surface ordinates and wing upper surface pressure levels and gradients. The design procedure also provides the capability of including directly in the optimization process the effects of other aircraft components such as a fuselage, canards, and nacelles.
    Keywords: AIRCRAFT DESIGN, TESTING AND PERFORMANCE
    Type: Proc. of the SCAR Conf., Part 1; p 9-24
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2019-06-27
    Description: A computerized study of operational parameters affecting helicopter fuel consumption was conducted as an integral part of the NASA Civil Helicopter Technology Program. The study utilized the Helicopter Sizing and Performance Computer Program (HESCOMP) developed by the Boeing-Vertol Company and NASA Ames Research Center. An introduction to HESCOMP is incorporated in this report. The results presented were calculated using the NASA CH-53 civil helicopter research aircraft specifications. Plots from which optimum flight conditions for minimum fuel use that can be obtained are presented for this aircraft. The results of the study are considered to be generally indicative of trends for all helicopters.
    Keywords: AIRCRAFT DESIGN, TESTING AND PERFORMANCE
    Type: NASA-TM-X-73922
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2019-06-27
    Description: Changes in future aircraft technology which conserve energy are studied, along with the effect of these changes on economic performance. Among the new technologies considered are laminar-flow control, composite materials with and without laminar-flow control, and advanced airfoils. Aircraft design features studied include high-aspect-ratio wings, thickness ratio, and range. Engine technology is held constant at the JT9D level. It is concluded that wing aspect ratios of future aircraft are likely to significantly increase as a result of new technology and the push of higher fuel prices. Composite materials may raise aspect radio to about 11 to 12 and practical laminar flow-control systems may further increase aspect ratio to 14 or more. Advanced technology provides significant reductions in aircraft take-off gross weight, energy consumption, and direct operating cost.
    Keywords: AIRCRAFT DESIGN, TESTING AND PERFORMANCE
    Type: NASA-TM-X-72833
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2019-06-27
    Description: Improved stability was provided in a hingeless helicopter rotor by inclining the principal elastic flexural axes and coupling pitching of the rotor blade with the lead-lag bending of the blade. The primary elastic flex axes were inclined by constructing the blade of materials that display non-uniform stiffness, and the specification described various cross section distributions and the resulting inclined flex axes. Arrangements for varying the pitch of the rotor blade in a predetermined relationship with lead-lag bending of the blade, i.e., bending of the blade in a plane parallel to its plane of rotation were constructed.
    Keywords: AIRCRAFT DESIGN, TESTING AND PERFORMANCE
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2019-07-13
    Description: Changes in future aircraft technology which conserve energy are studied, along with the effect of these changes on economic performance. Among the new technologies considered are laminar-flow control, composite materials with and without laminar-flow control, and advanced airfoils. Aircraft design features studied include high-aspect-ratio wings, thickness ratio, and range. Engine technology is held constant at the JT9D level. It is concluded that wing aspect ratios of future aircraft are likely to significantly increase as a result of new technology and the push of higher fuel prices. Whereas current airplanes have been designed for AR = 7, supercritical technology and much higher fuel prices will drive aspect ratio to the AR = 9-10 range. Composite materials may raise aspect ratio to about 11-12 and practical laminar flow-control systems may further increase aspect ratio to 14 or more. Advanced technology provides significant reductions in aircraft take-off gross weight, energy consumption, and direct operating cost.
    Keywords: AIRCRAFT DESIGN, TESTING AND PERFORMANCE
    Type: Annual Intersociety Conference on Transportation; Jul 18, 1976 - Jul 23, 1976; Los Angeles, CA
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2011-08-17
    Description: An overview of research, testing, and technology in the hypersonic range. Military and civilian hypersonic flight systems envisaged, ground testing facilities under development, methods for cooling the heated airframe, and use of hydrogen as fuel and coolant are discussed extensively. Air-breathing hypersonic cruise systems are emphasized, the airframe-integrated scramjet configuration is discussed and illustrated, materials proposed for hypersonic vehicles are reviewed, and test results on hypersonic flight (X-15 research aircraft) are indicated. Major advances and major problems in hypersonic flight and hypersonic technology are outlined, and the need for a hypersonic flying-laboratory research craft is stressed.
    Keywords: AIRCRAFT DESIGN, TESTING AND PERFORMANCE
    Type: Astronautics and Aeronautics; 14; Dec. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2011-08-16
    Description: Application of singular perturbation techniques to trajectory optimization problems of flight mechanics is discussed. The method of matched asymptotic expansions is used to obtain an approximate solution to the aircraft minimum time-to-climb problem. Outer, boundary-layer, and composite solutions are obtained to zeroth and first orders. A stability criterion is derived for the zeroth-order boundary-layer solutions (the theory requires a form of boundary-layer stability). A numerical example is considered for which it is shown that the stability criterion is satisfied and a useful numerical solution is obtained. The zeroth-order solution proves to be a poor approximation, but the first-order solution gives a good approximation for both the trajectory and the minimum time-to-climb. The computational cost of the singular perturbation solution is considerably less than that of a steepest descent solution. Thus singular perturbation methods appear to be promising for the solution of optimal control problems.
    Keywords: AIRCRAFT DESIGN, TESTING AND PERFORMANCE
    Type: AIAA Journal; 14; July 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2011-08-16
    Description: The paper reports the results of a conceptual design study of new near-term fuel-conservative aircraft. A parametric study was made to determine the effects of cruise Mach number and fuel cost on the optimum configuration characteristics and relative economic performance. Supercritical wing technology and advanced engine cycles were assumed. For each design, the wing geometry was selected to maximize an economic figure of merit which reflects the potential rate of return on investment. Based on the results of the parametric study, a reduced energy configuration was selected. Compared with existing transport design, the reduced energy design has a higher aspect ratio wing with lower sweep, and cruises at a slightly lower Mach number. It yields about 30% more seat-miles/gal than current wide-body aircraft. At the higher fuel costs anticipated in the future, the reduced energy design has about the same economic performance as existing designs with the same technology level. As an example of a far-term technology application, a design with a composite material wing was also investigated.
    Keywords: AIRCRAFT DESIGN, TESTING AND PERFORMANCE
    Type: Journal of Aircraft; 13; Aug. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2016-06-07
    Description: The modes to be observed during the F-15 flight flutter test program were selected on the basis of the results of analytical studies, wind tunnel tests, and ground vibration tests. The modes (both symmetrical and antisymmetrical) tracked on this basis were: fin first bending, fin torsion, fin tip roll, stabilator bending, stabilator pitch, boom lateral bending, boom torsion, boom vertical bending, wing first bending, wing second bending, wing first torsion, outer wing torsion, and aileron rotation. Data obtained for these various modes were evaluated in terms of damping versus airspeed at 1525 m (5000 ft), damping versus altitude at the cross-section Mach numbers (to extrapolate to the damping value to be expected at sea level), and flutter boundaries on the basis of flutter margin of various modal pairs representing potential flutter mechanisms. Results of these evaluations are summarized in terms of minimum predicted flutter margin for the various mechanisms.
    Keywords: AIRCRAFT DESIGN, TESTING AND PERFORMANCE
    Type: NASA. Langley Res. Center Flutter Testing Tech.; p 413-432
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2016-06-07
    Description: A flutter model, consisting of a wing, horizontal tail, and splitter plate/fuselage mechanism, was tested in a 4-foot transonic tunnel in the Mach number range 1.1 to 1.3. Two types of flutter were encountered during the testing: a wing-tail flutter bending-torsion flutter mode. The wing-tail flutter speed was found to be a minimum at M = 1.2 for the configuration tested. Recorded model test data were digitized for a power spectral density (PSD) analysis and Random Decrement (Randomdec) analysis. Comparisons between the frequency and damping obtained from the PSD plots and the Randomdec signatures agreed very well. A limited flutter analysis was conducted using a Mach box unsteady aerodynamics method which accounted for interference and airfoil thickness. Analytical comparisons with experimental flutter speeds agreed well. The analyses assuming zero thickness predicted flutter speeds higher than those measured, ranging from 1 percent at M = 1.12 to 8 percent at M = 1.28. With the airfoil thickness included, the correlation was improved such that predicted flutter speeds for all cases investigated were within 2 percent of experimental speeds.
    Keywords: AIRCRAFT DESIGN, TESTING AND PERFORMANCE
    Type: NASA. Langley Res. Center Flutter Testing Tech.,; p 193-212
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...