Effects of Simulated Ice Formation on the Aerodynamic Characteristics of an Airfoil (open access)

Effects of Simulated Ice Formation on the Aerodynamic Characteristics of an Airfoil

Report presenting an investigation of the size and distribution of ice particles on the wings of aircraft and how they affect the aerodynamic characteristics. A simulated ice formation was generated from survey information received from aircraft pilots and was tested to determine the impact on the lift characteristics.
Date: May 1938
Creator: Gulick, Beverly G.
System: The UNT Digital Library
Consideration of Auxiliary Jet Propulsion for Assisting Take-Off (open access)

Consideration of Auxiliary Jet Propulsion for Assisting Take-Off

Report presenting an analysis and simple method to help solve the problem of assisting the take-off of an airplane by means of auxiliary jet propulsion by determining the jet thrust and weight of jet fuel required to provide a desired reduction in take-off distance or increase in pay load or fuel load for a fixed take-off distance. The use of previous experimental work to verify the analysis is also provided.
Date: May 1940
Creator: Turner, L. Richard
System: The UNT Digital Library
Cylinder Barrel Cooling With Bonded Preformed Copper Fins (open access)

Cylinder Barrel Cooling With Bonded Preformed Copper Fins

Report presenting testing of preformed copper fins which were furnace-brazed to a steel-cylinder barrel. The barrel was electrically heated and blower-cooled to determine heat overall heat-transfer coefficient. Information regarding potential future adaptations of the fins are provided.
Date: May 1941
Creator: Foster, H. H. & Ellerbrock, H. H., Jr.
System: The UNT Digital Library
Effect of Propeller Operation on the Pitching Moments of Single-Engine Monoplanes (open access)

Effect of Propeller Operation on the Pitching Moments of Single-Engine Monoplanes

Report presenting an investigation of the effects of propeller operation on pitching moments with particular reference to the effect of propeller forces, the field of flow in the slipstream, and the increments of lift on the wing and the tail. A procedure, directly applicable only to single-engine monoplanes without flaps, has been set up for predicting the effect of propeller operation on pitching moments as well.
Date: May 1941
Creator: Goett, Harry J. & Pass, H. R.
System: The UNT Digital Library
A Brief Study of the Speed Reduction of Overtaking Airplanes by Means of Air Brakes (open access)

A Brief Study of the Speed Reduction of Overtaking Airplanes by Means of Air Brakes

"As an aid to airplane designers interested in providing pursuit airplanes with decelerating devices intended to increase the firing time when overtaking another airplane, formulas are given relating the pertinent distances and speeds in horizontal flight to the drag increase required. Charts are given for a representative parasite-drag coefficient from which the drag increase, the time gained, and the closing distance may be found. The charts are made up for three values of the ratio of the final speed of the pursuing airplane to the speed of the pursued airplane and for several values of the ratio of the speed of the pursued airplane to the initial speed of the pursuing airplane" (p. 1).
Date: May 1942
Creator: Pearson, H. A. & Anderson, R. F.
System: The UNT Digital Library
The Development of Satisfactory Flying Qualities on the Douglas Dive Bomber, Model SBD-1 Through Flight Testing Successive Modifications in Control-Surface Area, Hinge-Line Location, and Aerodynamic-Balance Nose Shape (open access)

The Development of Satisfactory Flying Qualities on the Douglas Dive Bomber, Model SBD-1 Through Flight Testing Successive Modifications in Control-Surface Area, Hinge-Line Location, and Aerodynamic-Balance Nose Shape

Report presenting flight-test data contributing to the development of the present SBD-1 flying qualities based on the interest expressed in the methods used to obtain control-force characteristics on the Douglas Model SBD-1 by minor relocation of control-surface hinge line in combination with modifications in the aerodynamic balance nose shape. Results regarding the stalling characteristics, lateral-directional stability and control, longitudinal stability and control, and design recommendations are provided.
Date: May 1942
Creator: Root, L. E.
System: The UNT Digital Library
High-Speed Tests of a Ducted Body with Various Air-Outlet Openings (open access)

High-Speed Tests of a Ducted Body with Various Air-Outlet Openings

Test of a ducted body with Internal flow were made in the 8-foot high-speed wind tunnel for the purpose of studying the effects on external drag and an critical speed of the addition of efficient inlet and outlet openings to a basic streamline shape. Drag tests of a 13.6- inch-diameter streamline body of fineness ratio 6.14 were made at Mach numbers ranging from 0.20 to 0.75. The model was centrally mounted on a 9-percent-thick airfoil and was designed to have an efficient airfoil-body juncture and a high critical speed.
Date: May 1942
Creator: Becker, John V. & Baals, Donald D.
System: The UNT Digital Library
High-speed tests of radial-engine nacelles on a thick low-drag wing (open access)

High-speed tests of radial-engine nacelles on a thick low-drag wing

Report presenting testing in the high-speed wind tunnel to determine the drag characteristics of several types of radial-engine nacelle on a low-drag airfoil. The drag coefficients of nacelles incorporating cowling-nose shapes shown by previous tests to be efficient and afterbodies of adequate length were about the same magnitude as commonly obtained for comparable installations on conventional wings. Results regarding the reduction of data, effect of nacelles on lift, and pressures at wing-nacelle juncture are provided.
Date: May 1942
Creator: Becker, John V.
System: The UNT Digital Library
Observations of the Improvement in Vision Brought About by the Application of a Rain-Repellent Lacquer on an Airplane Windshield (open access)

Observations of the Improvement in Vision Brought About by the Application of a Rain-Repellent Lacquer on an Airplane Windshield

"A rain-repellent lacquer was submitted to the National Advisory Committee for Aeronautics by Captain K.H. Kalberer, of Lorr Laboratories, and preliminary tests and observations have been made to determine its value in improving the vision through an airplane windshield during rain. The tests and observations were carried out at Ames Aeronautical Laboratory, Moffett Field, California, over a period of about a week. The results are reported herein" (p. 2).
Date: May 1942
Creator: McAvoy, William H. & Clousing, Lawrence A.
System: The UNT Digital Library
Analysis of Available Data on Control Surfaces Having Plain-Overhang and Frise Balances (open access)

Analysis of Available Data on Control Surfaces Having Plain-Overhang and Frise Balances

From Introduction: "The present paper deals with control surfaces having plain-overhang and Frise balances."
Date: May 1944
Creator: Purser, Paul E. & Toll, Thomas A.
System: The UNT Digital Library
Analysis of available data on the effectiveness of ailerons without exposed overhang balance (open access)

Analysis of available data on the effectiveness of ailerons without exposed overhang balance

From Introduction: "As a part of the general lateral-control investigation by the NACA, the large amount of two- and three-dimensional data on the rolling effectiveness of ailerons without exposed overhang balance is collected and analyzed in the present paper."
Date: May 1944
Creator: Crandall, Stewart M. & Swanson, Robert S.
System: The UNT Digital Library
An Analytical Investigation of the Effects of Elevator-Fabric Distortion on the Longitudinal Stability and Control of an Airplane (open access)

An Analytical Investigation of the Effects of Elevator-Fabric Distortion on the Longitudinal Stability and Control of an Airplane

From Summary: "The results of an analytical investigation to determine the qualitative effects of elevator-fabric distortion on the stick-force characteristics of an airplane are presented. These results indicate that serious alteration of intended stick-force characteristics can be produced by elevator-fabric distortion."
Date: May 1944
Creator: Mathews, Charles W.
System: The UNT Digital Library
Estimation of Pressures on Cockpit Canopies, Gun Turrets, Blisters, and Similar Protuberances (open access)

Estimation of Pressures on Cockpit Canopies, Gun Turrets, Blisters, and Similar Protuberances

Report presenting methods for estimating pressure distributions over protuberances such as cockpit canopies, gun turrets, blisters, scoops, and sighting domes. The methods are applied to the estimation of the pressure distributions over spherical segment and faired gun turrets and over the protuberances on the Brewster SB2A-1 airplane. The effects of compressibility, interference, and flow separation are discussed.
Date: May 1944
Creator: Wright, Ray H.
System: The UNT Digital Library
Profile-Drag Coefficients of Conventional and Low-Drag Airfoils as Obtained in Flight (open access)

Profile-Drag Coefficients of Conventional and Low-Drag Airfoils as Obtained in Flight

"The results of flight investigations of the profile drag of several carefully finished conventional and low-drag airfoils are presented. The results indicated that in all cases lower profile-drag coefficients were obtained with the low-drag than with the conventional airfoils over the range of lift coefficient tested and that, for comparable conditions of lift coefficient and Reynolds number, the low-drag airfoils may have profile-drag coefficients which are at least 27 percent lower than the profile-drag coefficients of the conventional airfoils" (p.1).
Date: May 1944
Creator: Zalovcik, John A.
System: The UNT Digital Library
Profile-Drag Coefficients of Conventional and Low-Drag Airfoils as Obtained in Flight (open access)

Profile-Drag Coefficients of Conventional and Low-Drag Airfoils as Obtained in Flight

Results of flight tests indicate that profile-drag coefficients which were obtained with the low-drag airfoils were lower than with the conventional types over the range of light coefficients tested. For comparable conditions of the lift coefficient and Reynolds Number, the low-drag airfoils have profile-drag coefficients which may be 27 percent lower than the profile drag of the conventional airfoils tested. Detailed results are presented graphically.
Date: May 1944
Creator: Zalovcik, John A.
System: The UNT Digital Library
Study of Jet-Propulsion System Comprising Blower, Burner, and Nozzle (open access)

Study of Jet-Propulsion System Comprising Blower, Burner, and Nozzle

"A study was made of the performance of a jet-propulsion system composed of an engine-driven blower, a combustion chamber, and a discharge nozzle. A simplified analysis is made of this system for the purpose of showing in concise form the effect of the important design variables and operating conditions on jet thrust, thrust horsepower, and fuel consumption. Curves are presented that permit a rapid evaluation of the performance of this system for a range of operating conditions" (p. 1).
Date: May 1944
Creator: Pinkel, Benjamin & Hall, Eldon W.
System: The UNT Digital Library
A correlation of the effects of compression ratio and inlet-air temperature on the knock limits of aviation fuels in a CFR engine 1 (open access)

A correlation of the effects of compression ratio and inlet-air temperature on the knock limits of aviation fuels in a CFR engine 1

Report presenting a method of correlating the effects of compression ratio and inlet-air temperature on the knock limits of aviation fuels. Knock-limited performance tests of several fuels were run to check the method.
Date: May 1945
Creator: Evvard, John C. & Branstetter, J. Robert
System: The UNT Digital Library
Flight Investigation of the Variation of Drag Coefficient With Mach Number for the Bell P-39N-1 Airplane (open access)

Flight Investigation of the Variation of Drag Coefficient With Mach Number for the Bell P-39N-1 Airplane

Report presenting an investigation of the effect of compressibility on the drag of a Bell P-39N-1 airplane in flight as part of a drag study on several high-speed airplanes for a range of Mach numbers.
Date: May 1945
Creator: Gasich, Welko E. & Clousing, Lawrence A.
System: The UNT Digital Library
Flight Tests of Dive-Recovery Flaps on an XP-51 Airplane (open access)

Flight Tests of Dive-Recovery Flaps on an XP-51 Airplane

Report presenting a flight investigation made to determine the effectiveness of dive-recovery flaps installed on the XP-51 airplane as a safety device for recovery from contemplated terminal-velocity dives. The flap installation is described and results are presented of measurements obtained during stick-free pull-ups and pull-outs made by deflecting the dive-recovery flaps to two selected values of flap angle .
Date: May 1945
Creator: Beeler, De E. & Williams, Walter C.
System: The UNT Digital Library
Preliminary Investigation of Supersonic Diffusers (open access)

Preliminary Investigation of Supersonic Diffusers

Report presenting the deceleration of air from supersonic velocities in channels. A normal shock in the diverging part of the diffuser is probably necessary for stable flow, and ways of minimizing the intensity of this shock have been developed.
Date: May 1945
Creator: Kantrowitz, Arthur & Donaldson, Coleman duP.
System: The UNT Digital Library
Investigations on Laminar Boundary-Layer Stability and Transition on Curved Boundaries (open access)

Investigations on Laminar Boundary-Layer Stability and Transition on Curved Boundaries

Report presenting an investigation of the transition of the boundary layer from the laminar to the turbulent region on a flat plate, on the concave and convex side of a plate with a 20-foot radius of curvature, and on the convex side of a plate with a 30-inch radius of curvature.
Date: May 1946
Creator: Liepmann, Hans W.
System: The UNT Digital Library
Stability and Control Force Tests of Four- and Six-Unit Wing Designs of Low Aspect Ratio and 20 Degree Triangular Plan Form (open access)

Stability and Control Force Tests of Four- and Six-Unit Wing Designs of Low Aspect Ratio and 20 Degree Triangular Plan Form

Report presenting an investigation to obtain force-test data on a wing design suitable for high-speed guided missiles, especially data on rolling moments produced in yawed and pitched attitudes. Force tests were conducted on two models of a wing design of low aspect ratio and 20 degree triangular plan form. Results regarding the application of results, four-unit wing design, and six-unit wing design are provided.
Date: May 1946
Creator: Paulson, John W.; Varney, Elizabeth P. & Johnson, Joseph L.
System: The UNT Digital Library