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Higgins, George J

Publications and source records attributed to Higgins, George J.

11 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1934

A study of the pitching moments and the stability characteristics of monoplanes

This note presents a study of the pitching moments and the stability characteristics of monoplanes. Expressions for the pitching-moment coefficient and the Diehl stability coefficient for the monoplane are developed, suitable for the use of airplane designers. The effective difference between the high-wing and low-wing types is portrayed and discussed. Comparisons between experimental and computed values are made. Charts for use in the solution of numerical values of the pitching-moment and stability coefficients are presented.

Higgins, George J↗
NASA NTRS1930

The prediction of airfoil characteristics

This report describes and develops methods by which the aerodynamic characteristics of an airfoil may be calculated with sufficient accuracy for use in airplane design. These methods for prediction are based on the present aerodynamic theory and on empirical formulas derived from data obtained in the N. A. C. A. variable density wind tunnel at a Reynolds number corresponding approximately to full scale. (author)

Higgins, George J↗
NASA NTRS1928

The effect of tip shields on a horizontal tail surface

A series of experiments made in the wind tunnel of the Daniel Guggenheim School of Aeronautics, New York University, on the effect of tip shields on a horizontal tail surface are described and discussed. It was found that some aerodynamic gain can be obtained by the use of tip shields though it is considered doubtful whether their use would be practical.

Dronin, Paul V↗
NASA NTRS1928

The Effect of a Flap and Ailerons on the N.A.C.A. M-6 Airfoil Section

This report contains the results obtained at the Langley Memorial Aeronautical Laboratory on an N. A. C. A. M-6 airfoil, fitted with a flap and ailerons, and tested in the variable density wind tunnel at a density of 20 atmospheres. Airfoil characteristics are given for the model up to 48 degree angle of attack with the flap set at various angles, and also with the ailerons set at similar angles. The approximate lift distribution and the center of pressure variation along the span are determined with the model at 18 degree angle of attack and with the ailerons displaced at 20 degrees. Approximate rolling moment and yawing moment coefficients are determined for the various aileron settings. A comparison of the calculated angles of zero lift and the calculated lift and moment coefficiencies with those observed is given in the appendix.

Higgins, George J↗
NASA NTRS1928

The Effect of the Walls in Closed Type Wind Tunnels

A series of tests has been conducted during the period 1925-1927 by the National Advisory Committee for Aeronautics in the variable-density wind tunnel on several airfoil models of different sizes and sections to determine the effect of tunnel-wall interference and to determine a correction which can be applied to reduce the error caused thereby. The use of several empirical corrections was attempted with little success. The Prandtl theoretical corrections give the best results, and their use is recommended for correcting closed wind tunnel results to the conditions of free air. An appendix is attached wherein the experimentally determined effect of the walls on the tunnel velocity very close to their surface is given. This is of special interest because a "scale effect" was found in the boundary layer with a change in the density of the tunnel air.

Higgins, George J↗
NASA NTRS1928

Tests on Models of Three British Airplanes in the Variable Density Wind Tunnel

This report contains the results of tests made in the National Advisory Committee for Aeronautics variable density wind tunnel on three airplane models supplied by the British Aeronautical Research Committee. These models, the BE-2E with R.A.F. 19 wings, the British Fighter with R.A.F. 15 wings, and the Bristol Fighter with R.A.F. 30 wings, were tested over a wide range in Reynolds numbers in order to supply data desired by the Aeronautical Research Committee for scale effect studies. The maximum lifts obtained in these tests are in excellent agreement with the published results of British tests, both model and full scale. No attempt is made to compare drag data, owing to the emission of tail surfaces, radiator, etc., from the model, but is shown that the scale effect observed on the drag coefficients in these tests is due to a large extent to the parts of the models other than the wings. (author)

Higgins, George J↗
NASA NTRS1927

Wall interference in closed type wind tunnels

A series of tests has been conducted by the National Advisory Committee for Aeronautics, in the variable density wind tunnel on several airfoils of different sizes and sections to determine the effect of tunnel wall interference and to determine a correction which can be applied to reduce the error caused thereby. The use of several empirical corrections was attempted with little success. The Prandtl theoretical correction gives the best results and its use is recommended for correcting closed wind tunnel results to conditions of free air.

Higgins, George J↗
NASA NTRS1926

The characteristics of the NACA M-12 airfoil section

The data obtained on the NACA M-12 airfoil, tested at twenty atmosphere density in the NACA variable density wind tunnel, have been extended by additional tests at one and at twenty atmospheres under improved conditions. The results of these tests are given. Considerable scale effect was found.

AIRFOILS - CLARK Y - CHAR & C P↗
NASA NTRS1926

The NACA CYH Airfoil Section

The NACA CYH airfoil section is described and its aerodynamic characteristics are given as tested in the NACA variable density wind tunnel at twenty atmosphere pressure. This section has a low drag, a high maximum lift, and a small travel of center of pressure.

Higgins, George J↗