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Results for “WINGS - POLARS”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
NASA NTRS1954

On the use of the indicial-function concept in the analysis of unsteady motions of wings and wing-tail combinations

The concept of indicial aerodynamic functions is applied to the analysis of the short-period pitching mode of aircraft. By the use of simple physical relationships associated with the indicial-function relationships concept, quantitative studies are made of the separate effects on the damping in pitch of changes in Mach number, aspect ratio, plan-form shape, and frequency. The concept is further shown to be of value in depicting physically the induced effects on a tail surface which follows in the wake of a starting forward surface. Considerable effort is devoted to the development of theoretical techniques whereby the transient response in lift at the tail to the wing wake may be estimated. Numerical results for several representative cases are presented, and these are analyzed to reassess the importance of the contribution to the rotary damping moment of the interference lift at the tail.

Tobak, Murray↗
NASA NTRS1996

Novel Composites for Wing and Fuselage Applications: Novel Wing Design Concepts - Task 1

Design trade studies were conducted to arrive at advanced wing designs that integrated new material forms with innovative structural concepts and cost-effective fabrication methods. A representative spar was selected for design, fabrication, and test to validate the predicted performance. Textile processes, such as knitting, weaving and stitching, were used to produce fiber preforms that were later fabricated into composite span through epoxy Resin Transfer Molding (RTM), Resin Film Infusion (RFI), and consolidation of commingled thermoplastic and graphite tows. The target design ultimate strain level for these innovative structural design concepts was 6000 mu in. per in. The spars were subjected to four-point beam bending to validate their structural performance. The various material form /processing combination Y-spars were rated for their structural efficiency and acquisition cost. The acquisition cost elements were material, tooling, and labor.

Suarez, J. A.↗
NASA NTRS1947

An Investigation of the Aerodynamic Characteristics of an 0.08-Scale Model of the Chance Vought XF7U-1 Airplane in the Langley High-Speed 7- by 10-Foot Tunnel. Part V - Wing-Alone Tests and Effect of Modifications to the Vertical Fins, Speed Brakes, and Fuselage TED No. NACA DE308: Wing-Alone Tests and Effect of Modifications to the Vertical Fins, Speed Brakes, and Fuselage, TED No. NACA DE308 - Part V

Tests have been conducted in the Langley high-speed 7- by 10-foot tunnel over a Mach number range from 0.40 to 0.91 to determine the stability and control characteristics of an 0.08-scale model of the Chance Vought XF7U-1 airplane. The wing-alone tests and the effect of the various vertical-fin modifications, speed-brake modifications, and fuselage modifications on the aerodynamic characteristics in pitch and yaw are presented in the present paper with a limited analysis of the results. Also included are tuft studies of the flow for some of the modifications tested.

Kuhri, Richard E.↗
NASA NTRS1947

Wind-Tunnel Tests of the 1/25-Scale Powered Model of the Martin JRM-1 Airplane. IV - Tests with Ground Board and with Modified Wing and Hull - TED No. NACA 232: Tests with Ground Board and with Modified Wing and Hull, TED No. NACA 232 - Part 4

Wind-tunnel tests were made of a 1/25 scale model of the Martin JRM-1 airplane to determine: (1) The longitudinal stability and control characteristics of the JRM-1 model near the water and lateral and directional stability characteristics with power while moving on the surface of the water, the latter being useful for the design of tip floats; (2) The stability and stalling characteristics of the wing with a modified airfoil contour; (3) Stability characteristics of a hull of larger design gross weight; The test results indicated that the elevator was powerful enough to trim the original model in a landing configuration at any lift coefficient within the specified range of centers of gravity. The ground-board tests for evaluating the aerodynamic forces and moments on an airplane in a simulated cross wind indicate a high dihedral effect in the presence of the ground board and, consequently, during low-speed taxying and take-off, large overturning moments would result which would have to be overcome by the tip floats.

Lockwood, Vernard E.↗
NASA NTRS2014

Fuzzy Model-based Pitch Stabilization and Wing Vibration Suppression of Flexible Wing Aircraft.

This paper presents a fuzzy nonlinear controller to regulate the longitudinal dynamics of an aircraft and suppress the bending and torsional vibrations of its flexible wings. The fuzzy controller utilizes full-state feedback with input constraint. First, the Takagi-Sugeno fuzzy linear model is developed which approximates the coupled aeroelastic aircraft model. Then, based on the fuzzy linear model, a fuzzy controller is developed to utilize a full-state feedback and stabilize the system while it satisfies the control input constraint. Linear matrix inequality (LMI) techniques are employed to solve the fuzzy control problem. Finally, the performance of the proposed controller is demonstrated on the NASA Generic Transport Model (GTM).

Stability and Control↗
NASA NTRS2017

Commercial Cargo Derivative Study of the Advanced Hybrid Wing Body Configuration with Over-Wing Engine Nacelles

LM has leveraged our partnership with the Air Force Research Laboratory (AFRL) and NASA on the advanced hybrid wing body (HWB) concept to develop a commercial freighter which addresses the NASA Advanced Air Transport Technology (AATT) Project goals for improved efficiency beyond 2025. The current Air Force Research Laboratory (AFRL) Revolutionary Configurations for Energy Efficiency (RCEE) program established the HWB configuration and technologies needed for military transports to achieve aerodynamic and fuel efficiencies well beyond the commercial industry's most modern designs. This study builds upon that effort to develop a baseline commercial cargo aircraft and two HWB derivative commercial cargo aircraft to quanitify the benefit of the HWB and establish a technology roadmap for further development.

Hooker, John R.↗
NASA NTRS2019

Evaluation of Wing Load Calibration and Sensing Methods Using Conventional Strain Gages and a Fiber Optic Sensing System Installed on a Straight Tapered Wing

This presentation presents the results from a wing load test in the FLL (Flight Loads Lab). Load calibration techniques for strain gages and fiber optics were compared and contrasted. This presentation has the potential to lead to more research testing at NASA Armstrong in the areas of load calibration technology.

load calibrations↗