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open access

Effect of Chordwise Vanes on Amplitude of Tail Buffeting

Description: "Flight tests have been made with a P-51D airplane to determine the effect of chordwise vanes on the amplitude of tail buffeting. The tests made during abrupt pull-ups to the buffeting boundary included strain measurements on wing and tail and tuft studies over the wing. The results indicate that the vanes tested have no appreciable effect on the amplitude of tail buffeting" (p. 1).
Date: November 10, 1947
Creator: Stokke, Allen R.
open access

An investigation of the effect of tip shape on the low-speed aerodynamic characteristics of large-scale swept wings

Description: Report presenting an investigation of the effect of tip shape on the aerodynamic characteristics of large-scale 45 degrees swept-forward and 45 degrees swept-back wings. The results show that none of the variations of tip shape investigated nor the addition of bodies of revolution at the tips produced major changes in the characteristics of the swept wings.
Date: November 13, 1947
Creator: Walling, Walter C.
open access

Flight Investigation to Determine the Hinge Moments of a Beveled-Edge Aileron on a 45 Degree Sweptback Wing at Transonic and Low Supersonic Speeds

Description: Report discussing testing of a model of the pilotless aircraft RM-1 to measure aileron hinge moments in flight in order to determine the reason for loss of roll stabilization at supercritical speeds in flight. The aileron was found to become quickly underbalanced over the full deflection range at supercritical speeds. Information about the general flight behavior, aileron hinge moments, and roll stabilization of the model is provided.
Date: November 12, 1947
Creator: Gardner, William N. & Curfman, Howard J., Jr.
open access

Aerodynamic characteristics at subcritical and supercritical Mach numbers of two airfoil sections having sharp leading edges and extreme rearward positions of maximum thickness

Description: From Introduction: "A 12-percent-chord-thick wedge section and a reversed NACA 0012 section were chosen for these tests as they are representative of sections having no boat tailing and appreciable boat tailing (i.e., blunt and rounded trailing edges, respectively), and the results of this investigation are compared with those obtained from a previous investigation of the NACA 0012 section. Conclusions are drawn regarding the relative merits of the two unconventional sections and the convention… more
Date: November 6, 1947
Creator: Eggers, A. J., Jr.
open access

Preliminary evaluation of the performance of a uniflow two-stroke-cycle spark-ignition engine combined with a blowdown turbine and a steady-flow turbine

Description: Report presenting calculations based on a theoretical analysis for a composite engine consisting of a uniflow two-stroke-cycle spark-ignition engine, a compressor, a blowdown turbine, and a steady-flow turbine. Operation of the engine is considered for four cases of gas mixtures and steady-flow turbine temperatures.
Date: November 25, 1947
Creator: Sather, Bernard I. & Foster, Hampton H.
open access

Preliminary Tank Tests of NACA Hydro-Skis for High-Speed Airplanes

Description: Report presenting the results from tank landing and take-off tests with a dynamic model of a hypothetical jet-propelled airplane equipped with NACA hydro-skis. Results regarding landing tests, take-off tests, and practical considerations for the creation of hydro-ski configurations are provided. The hydro-skis suitable for flush retraction into streamline fuselages do appear to offer a practical means of water take-offs and landings.
Date: November 26, 1947
Creator: Dawson, John R. & Wadlin, Kenneth L.
open access

Downwash in Vortex Region Behind Trapezoidal-Wing Tip at Mach Number 1.91

Description: Report presenting the results of an experimental investigation to determine the downwash in the region of the trailing vortex behind a trapezoidal-wing tip in a supersonic stream. Results regarding the downwash at spanwise stations, downwash at chordwise stations, and wake survey are provided.
Date: November 10, 1949
Creator: Cummings, J. L.; Mirels, H. & Baughman, L. E.
open access

Wing-tunnel investigation at low transonic speeds of the effects of number of wings on the lateral-control effectiveness of an RM-5 test vehicle

Description: Report presenting an investigation to determine the effects of number of wings on the aileron rolling effectiveness of an RM-5 test vehicle using the free-rolling wind-tunnel testing technique through a speed range to Mach number 0.9. The wings tested had neither taper nor sweepback and were equipped with full-span 20-percent-chord sealed and faired ailerons. Results indicated that increasing the number of wings resulted in a decrease in rolling effectiveness so that results obtained from the t… more
Date: November 29, 1949
Creator: Johnson, Harold S.
open access

Spin-Tunnel Investigation of the Jettisoning of External Fuel Tanks in Spins

Description: "A spin-tunnel investigation has been made to determine the probability of external fuel tanks striking an airplane after being jettisoned in a spin. The investigation showed that for straight-wing fighter-type designs in any case in which jettisoning of tanks in a spin might aid spin recovery the tanks would probably clear all parts of the airplane" (p. 1).
Date: November 30, 1949
Creator: Berman, Theodore
open access

Analytical determination of effect of water injection on power output of turbine-propeller engine

Description: From Introduction: "Water injection at the compressor inlet has been successfully used to increase the thrust of turbojet engines. References 1 and 2 indicate that the sea-level static thrust of a centrifugal-flow-type turbojet engine may be increased about 25 percent by use of liquid injection. Reference 3 indicates that greater thrust augmentation is possible at a compressor pressure ratio of 11 than of 4."
Date: November 3, 1949
Creator: Ross, Albert O. & Huppert, Merle C.
open access

Precautions for Flight Testing Near the Speed of Sound

Description: From experience gained by NACA test pilots in flying at high subsonic Mach numbers and from interpretation of the data obtained, some general precautionary rules for test flying near sonic Mach numbers have been formulated. The reasons for these rules are discussed and observations are made with respect to the hazards arising from undesirable stability and control characteristics which have been noted in test flights of various airplanes. This paper, although written primarily for the attention… more
Date: November 5, 1947
Creator: Clousing, Lawrence A.
open access

Comparison between flight-measured and calculated span load distribution at high Mach numbers

Description: Report presenting an analysis of the spanwise loading using two different methods on the wing of an airplane for which pressure-distribution measurements were available from flight tests up to a Mach number of 0.866. A comparison between measured and calculated distributions was made on the basis of equal wing-panel normal-force coefficients.
Date: November 26, 1947
Creator: Rolls, L. Stewart
open access

Wing-flow tests of a triangular wing of aspect ratio two 1: effectiveness of several types of trailing-edge flaps on flat-plate models

Description: Report presenting an investigation of the problem of applying controls to low-aspect-ratio wings of triangular plan form by using the NACA wing-flow method with parallel-sided models with sharp leading and trailing edges. Results regarding the data analysis, Reynolds number and separation effects, flap effectiveness, plan-form characteristics, angle of zero lift, and triangular plan-form flying-wing characteristics are provided.
Date: November 14, 1947
Creator: Rathert, George A., Jr. & Cooper, George E.
open access

The Effect of Boundary-Layer Control by Suction and Several High-Lift Devices on the Longitudinal Aerodynamic Characteristics of a 47.5 Degree Sweptback Wing-Fuselage Combination

Description: "An investigation has been made in the Langley full-scale tunnel of a 47.5 degree sweptback wing-fuselage combination equipped for boundary-layer control by suction. The wing aspect ratio was 3.5, the taper ratio was 0.5, and the airfoil sections normal to the quarter-chord line were NACA 64(sub 1)-A112. The wing configurations tested included the wing with various combinations of extensible leading-edge and split flaps" (p. 1).
Date: November 4, 1948
Creator: Pasamanick, Jerome & Proterra, Anthony J.
open access

Investigation of interaction effects arising from side-wall boundary layers in supersonic wind-tunnel tests of airfoils

Description: Report presenting an investigation to determine the cause for a discrepancy between theoretical and experimental pressure distributions found during a two-dimensional investigation of flapped airfoils in a 2- by 8-inch supersonic tunnel. The results indicated that a tunnel-boundary-layer and model-flow interaction effect on the flow over models mounted directly from the walls in supersonic wind tunnels exists.
Date: November 3, 1948
Creator: Czarnecki, K. R. & Schueller, C. F.
open access

Investigation of the Effect of Sweep on the Flutter of Cantilever Wings

Description: Report presenting an experimental and analytical investigation of the flutter of uniform sweptback cantilever wings. The experiments used groups of wings sweptback by rotating and by shearing with angles of sweep ranging from 0 to 60 degrees. Results regarding the experimental investigation and a discussion and comparison of the analytical and experimental results are provided.
Date: November 15, 1948
Creator: Barmby, J. G.; Cunningham, H. J. & Garrick, I. E.
open access

Transonic-Flutter Investigation of Wings Attached to Two Low-Acceleration Rocket-Propelled Vehicles

Description: Two low-acceleration transonic-flutter vehicles were launched and flown. The first carried two test wings, one of which fluttered at M = 0.92 at a frequency of 61.4 cycles per second. The reference flutter speed determined from two-dimensional theory for an unswept wing in incompressible flow is conservative when compared to the experimental flutter speed. The second vehicle carried two test wings, one of which failed at M = 0.71 because of low-frequency divergent oscillation. Since this failur… more
Date: November 23, 1948
Creator: Lundstrom, Reginald R.; Lauten, William T., Jr. & Angle, Ellwyn E.
open access

Static longitudinal aerodynamic characteristics of a 52 degree sweptback wing of aspect ratio 2.88 at Reynolds numbers from 2,000,000 to 11,000,000

Description: Report presenting the effects of changes in Reynolds number on the longitudinal aerodynamic characteristics of a 52 degree sweptback wing with an aspect ratio of 2.88 and NACA 64(sub 1)-112 airfoil sections. The model was tested with the leading edge both smooth and rough. Results regarding force and pitching-moment results, flow observations, and discussion of force and moment characteristics are provided.
Date: November 16, 1948
Creator: Fitzpatrick, James E. & Foster, Gerald V.
open access

Model ditching investigation of the Douglas DC-4 and DC-6 airplanes

Description: Report presenting the ditching characteristics of the Douglas DC-4 and DC-6 in a water tank. Dynamically similar models of 1/16 scale were used for the investigation, which was conducted in calm and rough water. The ditching characteristics and safest ditching procedures were determined by testing at various landing attitudes, speeds, and simulated conditions of damage.
Date: November 8, 1949
Creator: Fisher, Lloyd J. & Hoffman, Edward L.
open access

Low-Speed Characteristics in Pitch of a 42 Degree Sweptback Wing With Aspect Ratio 3.9 and Circular-Arc Airfoil Sections

Description: Report presenting tests in a pressure tunnel to determine the low-speed pitch characteristics of a 42 degree sweptback wing with circular-arc airfoil sections. Information regarding the characteristics of basic wing, leading-edge flap investigation, and effects of fuselage are provided.
Date: November 13, 1947
Creator: Neely, Robert H. & Koven, William
open access

Reduction of profile drag at supersonic velocities by the use of airfoil sections having a blunt trailing edge

Description: Report presenting a preliminary theoretical and experimental investigation of the supersonic characteristics of blunt-trailing-edge airfoils. Results regarding the drag measurements at zero lift, measurements at angle of attack, and a general discussion of the theoretical and experimental results is provided.
Date: November 1, 1949
Creator: Chapman, Dean R.
open access

Low-speed pressure-distribution and flow investigation for a large pitch and yaw range of three low-aspect-ratio pointed wings having leading edge swept back 60 degrees and biconvex sections

Description: Report presenting an investigation of pressure distributions and flow characteristics at low speed through a range of yaw and angle of attack through the stall for three small-scale low-aspect-ratio pointed wings with varying degrees of trailing-edge sweep. An effort was made to correlate pressure distributions with the strong conical vortex flow observed. Results regarding chordwise pressure distributions and flow characteristics, section lift characteristics at zero yaw, spanwise-load distrib… more
Date: November 18, 1949
Creator: May, Ralph W., Jr. & Hawes, John G.
open access

Vibration of loosely mounted turbine blades during service operation of a turbojet engine with centrifugal compressor and straight-flow combustion chambers

Description: Report presenting an experimental investigation to determine the vibration characteristics of loosely mounted turbine blades during service operation of a turbojet engine. High-temperature strain gages were used to measure turbine-blade vibrations. Results regarding oscillograph records, critical speeds and frequencies, vibratory-stress levels, and effect of tightening the blade mount are provided.
Date: November 3, 1949
Creator: Morgan, W. C.; Kemp, R. H. & Manson, S. S.
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