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The Effects of Roughness at High Reynolds Numbers on the Lift and Drag Characteristics of Three Thick Airfoils (open access)

The Effects of Roughness at High Reynolds Numbers on the Lift and Drag Characteristics of Three Thick Airfoils

"In connection with studies of airfoils applicable to large high-speed aircraft, the effects of roughness on three 22-percent-thick airfoils were investigated. The tests were made over a range of Reynolds number from about 6 to 26 x 10(exp 6) for the airfoils smooth and with roughness strips applied to the surfaces. The results indicated that for the roughened models the scale effect was generally favorable" (p. 1).
Date: August 1944
Creator: Abbott, Frank T., Jr. & Turner, Harold R., Jr.
Object Type: Report
System: The UNT Digital Library
Knock-limited performance of blends of AN-F-28 fuel containing 2 percent aromatic amines 3 (open access)

Knock-limited performance of blends of AN-F-28 fuel containing 2 percent aromatic amines 3

Report presenting tests to investigate the effect of 2-percent additions of nine aromatic amines on the knock-limited performance of AN-N-28 (28-R) fuel. The results of the testing of antiknock effectivneess of the 27 aromatic amines obtained to date in the program are also summarized.
Date: August 1944
Creator: Alquist, Henry E. & Tower, Leonard K.
Object Type: Report
System: The UNT Digital Library
Neutron Emission by Polonium Oxide Layers (open access)

Neutron Emission by Polonium Oxide Layers

The following report calculates how many neutrons are produced by the O-16([alpha]-n) reaction in a thin and uniform polonium oxide layer.
Date: August 8, 1944
Creator: Argo, M. & Teller, E.
Object Type: Report
System: The UNT Digital Library
Charts for estimation of the characteristics of a helicopter rotor in forward flight I: profile drag-lift ratio for untwisted rectangular blades (open access)

Charts for estimation of the characteristics of a helicopter rotor in forward flight I: profile drag-lift ratio for untwisted rectangular blades

Report presenting charts showing the rotor profile drag-lift ratio for a helicopter rotor operating in forward flight and having hinged rectangular untwisted blades. The charts are given for a range of power input covering glides, level flight, and moderate rates of climb. A drag curve was used for preparing the charts, and the curve is compared with experimental curves for typical airfoils.
Date: August 1944
Creator: Bailey, F. J., Jr.
Object Type: Report
System: The UNT Digital Library
Supercharged-Engine Knock Tests of Methyl Tert-Butyl Ether (open access)

Supercharged-Engine Knock Tests of Methyl Tert-Butyl Ether

Report presenting data that show the knock-limited performance of methyl tert-butyl ether obtained from tests made in a 17.6-cubic-inch-displacement engine under supercharged conditions. Tests for temperature sensitivity, speed sensitivity, and lead susceptibility were made on a blend of 20 percent methyl tert-butyl ether and 80 percent S-2 reference fuel.
Date: August 1944
Creator: Barnett, Henry C. & Slough, James W., Jr.
Object Type: Report
System: The UNT Digital Library
Engine and inspection tests of methyl tert-butyl ether as a component of aviation fuel (open access)

Engine and inspection tests of methyl tert-butyl ether as a component of aviation fuel

Report presenting an investigation of the suitability of methyl tert-butyl ether as a component of aviation fuel from considerations of knock-limited performance tests and laboratory inspection tests. Data were obtained from testing on the 17.6 engine under supercharged conditions with fuel blends containing 10 and 20 percent methyl tert-butyl ether. Results regarding small-scale-engine data, full-scale-engine data, and inspection data are provided.
Date: August 1944
Creator: Barnett, Henry C.; Meyer, Carl L. & Jones, Anthony W.
Object Type: Report
System: The UNT Digital Library
The NACA Impact Basin and Water Landing Tests of a Float Model at Various Velocities and Weights (open access)

The NACA Impact Basin and Water Landing Tests of a Float Model at Various Velocities and Weights

Report presenting data obtained when a float with both horizontal and vertical velocity contact on a water surface. The report is confined to a presentation of the relationship between resultant velocity and impact normal acceleration for various float weights when all other parameters are constant.
Date: August 1944
Creator: Batterson, Sidney A.
Object Type: Report
System: The UNT Digital Library
Continuous Use of Internal Cooling to Suppress Knock in Aircraft Engines Cruising at High Power (open access)

Continuous Use of Internal Cooling to Suppress Knock in Aircraft Engines Cruising at High Power

Report presenting an investigation of the possibility of using internal cooling instead of fuel enrichment to suppress knock and to estimate the fuel savings that will result. Data from four different sources was examined and an analysis of the fuel consumption was conducted. Four different types of coolants were explored.
Date: August 1944
Creator: Bell, Arthur H.
Object Type: Report
System: The UNT Digital Library
Axial Superchargers (open access)

Axial Superchargers

Improvements, however, have been attained which permit a shortening of the structure without any impairment of the efficiency. The axial supercharger has a better efficiency and a simpler design than the radial supercharger. The relatively narrow range in which it operates satisfactorily should not be a very disturbing factor for practical flight problems. The length of this type of supercharger may be reduced considerably if some impairment in the efficiency is permitted.
Date: August 1944
Creator: Betz, A.
Object Type: Report
System: The UNT Digital Library
The Surface Structure of Ground Metal Crystals (open access)

The Surface Structure of Ground Metal Crystals

"The changes produced on metallic surfaces as a result of grinding and polishing are not as yet fully understood. Undoubtedly there is some more or less marked change in the crystal structure, at least, in the top layer. Hereby a diffusion of separated crystal particles may be involved, or, on plastic material, the formation of a layer in greatly deformed state, with possible recrystallization in certain conditions" (p. 1).
Date: August 1944
Creator: Boas, W. & Schmid, E.
Object Type: Report
System: The UNT Digital Library
An Investigation of Aircraft Heaters 14: Performance of Two Finned-Type Crossflow Exhaust Gas and Air Heat Exchangers (open access)

An Investigation of Aircraft Heaters 14: Performance of Two Finned-Type Crossflow Exhaust Gas and Air Heat Exchangers

Report presenting data on the thermal performance and the static pressure drop characteristics of two finned-type exhaust gas and air heat exchangers. One heater was constructed of copper and stainless steel while the other was constructed from aluminum alloy. The measured thermal outputs and static pressure drops are compared with predicted magnitudes.
Date: August 1944
Creator: Boelter, L. M. K.; Guibert, A. G.; Rademacher, J. M. & Sloggy, L. J. B.
Object Type: Report
System: The UNT Digital Library
An investigation of aircraft heaters 17: experimental inquiry into steady state unidirectional heat-meter corrections (open access)

An investigation of aircraft heaters 17: experimental inquiry into steady state unidirectional heat-meter corrections

Report divided into two sections. One discusses a correction that must be applied to a heat meter when it is used at temperatures other than temperatures at which it was calibrated. The other section contains the results of an application of the two methods of correcting the heat-transfer rates for contact and heat-meter resistance to experimental data.
Date: August 1944
Creator: Boelter, L. M. K.; Poppendiek, H. F. & Gier, J. T.
Object Type: Report
System: The UNT Digital Library
Coating of tubealloy slugs (open access)

Coating of tubealloy slugs

None
Date: August 5, 1944
Creator: Boller, E. R.
Object Type: Report
System: The UNT Digital Library
Charts for Calculation of the Critical Compressive Stress for Local Instability of Idealized Web- and T-Stiffened Panels (open access)

Charts for Calculation of the Critical Compressive Stress for Local Instability of Idealized Web- and T-Stiffened Panels

"Charts are presented for the calculation of the critical compressive stress - the stress at which local instability occurs - for idealized web- and T-stiffened panels, and examples of the use of the charts are given" (p. 1).
Date: August 1944
Creator: Boughan, Rolla B. & Baab, George W.
Object Type: Report
System: The UNT Digital Library
Wind-tunnel investigation of aileron effectiveness of 0.20-airfoil-chord plain ailerons of true airfoil contour on NACA 65(sub 2)-415, 65(sub 3)-418 and 65(sub 4)-421 airfoil sections (open access)

Wind-tunnel investigation of aileron effectiveness of 0.20-airfoil-chord plain ailerons of true airfoil contour on NACA 65(sub 2)-415, 65(sub 3)-418 and 65(sub 4)-421 airfoil sections

Report presenting an investigation in the two-dimensional low-turbulence pressure tunnel to determine the aileron effectiveness of 0.20-airfoil-chord plain ailerons of true airfoil contour on three different airfoil sections. The aileron effectiveness parameter decreased very slightly with an increase in airfoil thickness. Results regarding the plain-airfoil section characteristics, aileron effectiveness, lift characteristics, and effects of airfoil thickness are provided.
Date: August 1944
Creator: Braslow, Albert L.
Object Type: Report
System: The UNT Digital Library
Gas Jets (open access)

Gas Jets

"A brief summary of the contents of this paper is presented here. In part I the differential equations of the problem of a gas flow in two dimensions is derived and the particular integrals by which the problem on jets is solved are given. Use is made of the same independent variables as Molenbroek used, but it is found to be more suitable to consider other functions. The stream function and velocity potential corresponding to the problem are given in the form of series" (p. 1).
Date: August 1944
Creator: Chaplygin, S.
Object Type: Report
System: The UNT Digital Library
Application of the method of least squares to engine-cooling analysis (open access)

Application of the method of least squares to engine-cooling analysis

From Introduction: "The purpose of this report is to show that it is practical to apply a least-squares method to the correlation of engine-cooling data."
Date: August 1944
Creator: Corson, Blake W., Jr.
Object Type: Report
System: The UNT Digital Library
An Interim Report on the Stability and Control of Tailless Airplanes (open access)

An Interim Report on the Stability and Control of Tailless Airplanes

Problems relating to the stability and control of tailless airplanes are discussed in consideration of contemporary experience and practice.
Date: August 19, 1944
Creator: Donlan, Charles J.
Object Type: Report
System: The UNT Digital Library
An Interim Report on the Stability and Control of Tailless Airplanes (open access)

An Interim Report on the Stability and Control of Tailless Airplanes

Problems relating to the stability and control of tailless airplanes are discussed in consideration of contemporary experience and practice.
Date: August 19, 1944
Creator: Donlan, Charles J.
Object Type: Report
System: The UNT Digital Library
Use of Water Injection to Decrease Gasoline Consumption in an Aircraft Engine Cruising at High Power (open access)

Use of Water Injection to Decrease Gasoline Consumption in an Aircraft Engine Cruising at High Power

Report discusses the results of testing water injection on a multicylinder aircraft engine and the potential fuel savings from the procedure. The speeds at which water injection for engine cooling is beneficial are illustrated and information about the manifold pressures and average rear spark-plug-gasket temperatures are also included.
Date: August 1944
Creator: Engelman, Helmuth W. & White, H. Jack
Object Type: Report
System: The UNT Digital Library
Ditching Tests With a 1/12-Size Model of the Army B-26 Airplane in NACA Tank Number 2 and on an Outdoor Catapult (open access)

Ditching Tests With a 1/12-Size Model of the Army B-26 Airplane in NACA Tank Number 2 and on an Outdoor Catapult

Report presenting tests made with a dynamic model of the Army B-26 airplane to determine its behavior when landed on water. Results regarding the general behavior, effect of flaps, effect of landing attitude and speed, tests with undamaged model, tests with simulated damage, tests with propellers, vertical decelerations, and effect of weight are provided.
Date: August 1944
Creator: Fisher, Lloyd J. & Steiner, Margaret F.
Object Type: Report
System: The UNT Digital Library
Analysis of Vertical-Tail Loads in Rolling Pull-Out Maneuvers (open access)

Analysis of Vertical-Tail Loads in Rolling Pull-Out Maneuvers

Bulletin presenting an analysis of the vertical-tail loads to be expected as a result of abrupt aileron action in accelerated flight, as in rolls from turns or pull-outs, for example. Critical tail loads may occur in rolling pull-out maneuvers, particularly on airplanes with good ailerons and low directional stability.
Date: August 1944
Creator: Gilruth, Robert R.
Object Type: Report
System: The UNT Digital Library
Effect of Helicopter Performance of Modifications in Profile-Drag Characteristics of Rotor-Blade Airfoil Sections (open access)

Effect of Helicopter Performance of Modifications in Profile-Drag Characteristics of Rotor-Blade Airfoil Sections

Rough conventional, smooth conventional, and laminar-flow or low-drag sections were tested. The items covered are rotor thrust for fixed power in hovering, range and endurance at cruising speed, and power required at high-forward speed. Calculations indicated that a smooth conventional section gives marked performance gains. Smaller gains are obtainable by using a low-drag section. At high speeds or loads the low-drag section is inferior to the smooth conventional section.
Date: August 1944
Creator: Gustafson, F. B.
Object Type: Report
System: The UNT Digital Library
An Experimental Investigation of the Thrust and Torque Produced by Propellers Used as Aerodynamic Brakes (open access)

An Experimental Investigation of the Thrust and Torque Produced by Propellers Used as Aerodynamic Brakes

Report presenting the results of a wind-tunnel investigation of propellers operating at negative thrust. Negative-thrust characteristics of two- and four-blade single propellers and four- and eight-blade dual propellers were determined. The results indicate that the constant-speed reversed-pitch propellers posses aerodynamic characteristics that should make them excellent aerodynamic brakes.
Date: August 1944
Creator: Hedrick, William S. & Douglass, William M.
Object Type: Report
System: The UNT Digital Library