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The 1933 Contest for the Deutsch De La Meurthe Trophy
Report discussing the regulations and airplanes participating in the 1933 contest competing for the Deutsch de la Meurthe trophy.
The Aerodynamic Characteristics of Airfoils as Affected by Surface Roughness
"The effect on airfoil characteristics of surface roughness of varying degrees and types at different locations on an airfoil was investigated at high values of the Reynolds number in a variable density wind tunnel. Tests were made on a number of National Advisory Committee for Aeronautics (NACA) 0012 airfoil models on which the nature of the surface was varied from a rough to a very smooth finish. The effect on the airfoil characteristics of varying the location of a rough area in the region of the leading edge was also investigated" (p. 1).
The Aerodynamic Effect of a Retractable Landing Gear
"Tests were conducted in the N.A.C.A. full scale wind tunnel at the request of the Army Air Corps to determine the effect of retractable landing gear openings in the bottom surface of a wing upon the characteristics of a Lockheed Altair airplane. The tests were extended to include the determination of the lift and drag characteristics throughout the angle-of-attack range with the landing gear both retracted and extended. Covering the wheel openings in the wing with sheet metal when the wheels were extended reduced the drag only 2 percent at a lift coefficient of 1.0, which was assumed for the take-off condition" (p. 1).
The Aerodynamic Forces and Moments Exerted on a Spinning Model of the NY-1 Airplane as Measured by the Spinning Balance
From Summary: "A preliminary investigation of the effects of changes in the elevator and rudder settings and of small changes in attitude upon the aerodynamic forces and moments exerted upon a spinning airplane was undertaken with the spinning balance in the 5-foot vertical tunnel of the National Advisory Committee for Aeronautics. The tests were made on a 1/12-scale model of the "NY-1" airplane. Data by which to fix the attitude, the radius of spin, and the rotational and air velocities were taken from recorded spins of the full-scale airplane."
Aerodynamic forces and moments of a seaplane on the water
From Introduction: "This report gives the results of wind-tunnel tests with a seaplane model as a contribution to the solution of the aerodynamic problems."
Aerodynamic tests of a low aspect ratio tapered wing with an auxiliary airfoil for use on tailless airplanes
From Introduction: "The present report gives the results of tests made on a tapered wing with a nontapered auxiliary airfoil affixed to it. The wing was the one used in reference 7."
Aerodynamic tests of a low aspect ratio tapered wing with various flaps, for use on tailless airplanes
From Introduction: "The tests described in this report are the first in an investigation by N.A.C.A. of the aerodynamic characteristics of possible tailless arrangements. The investigations will be extended to include whatever range is through most desirable and may include, among other things, variations in aspect ratio, taper, sweepback, washout, air-foil section, dihedral, and also control flaps or other control devices of different forms and proportions."
Aircraft Power-Plant Instruments
From Summary: "The report includes a description of the commonly used types and some others, the underlying principle utilized in the design, and some design data. The inherent errors of the instrument, the methods of making laboratory tests, descriptions of the test apparatus, and data in considerable detail in the performance of commonly used instruments are presented. Standard instruments and, in cases where it appears to be of interest, those used as secondary standards are described."
Aircraft speed instruments
From Summary: "This report presents a concise survey of the measurement of air speed and ground speed on board aircraft. Special attention is paid to the Pitot-static air-speed meter which is the standard in the United States for airplanes. A bibliography on air-speed measurement concludes the report."
An airfoil spanning an open jet
From Summary: "The first part of the report treats of the theory involved. The second part describes the experiments performed for the purpose of proving the theory."
The Airspeed "Courier" Commercial Airplane (British): A Low-Wing Cantilever Monoplane
Circular presenting a description of the first British airplane with a retractable landing gear, which is a small and aerodynamically clean monoplane. A description of the design and flight characteristics is provided.
Annual Report of the National Advisory Committee for Aeronautics (18th). Administrative Report Including Technical Report Nos. 401 to 440
Report includes the National Advisory Committee for Aeronautics letter of submittal to the President, Congressional report, summaries of the committee's activities and research accomplished, bibliographies, and financial report.
Application of Practical Hydrodynamics to Airship Design
The purpose of the first two parts of this report is to present in concise format all the formulas required for computation of the hydrodynamic forces, so that they can be easily computed for either straight or curvilinear flight. Improved approximations are also introduced having a high degree of accuracy throughout the entire range of practical proportions. The remaining two parts of the report are devoted respectively to stability and skin friction, as functions of the same hydrodynamic forces.
Attaining a Steady Air Stream in Wind Tunnels
"Many experimental arrangements of varying kind involve the problems of assuring a large, steady air stream both as to volume and to time. For this reason a separate discussion of the methods by which this is achieved should prove of particular interest. Motors and blades receive special attention and a review of existent wind tunnels is also provided" (p. 1).
Behavior of Vortex Systems
Progressive application of the Kutta-Joukowsky theorem to the relationship between airfoil lift and circulation affords a number of formulas concerning the conduct of vortex systems. The application of this line of reasoning to several problems of airfoil theory yields an insight into many hitherto little observed relations. This report is confined to plane flow, hence all vortex filaments are straight and mutually parallel (perpendicular to the plane of flow).
The Boulton and Paul P.64 Mail-Carrier: A Two-Engine All-Metal Biplane
Circular presenting a description of the Boulton and Paul P.64 high-performance mail-carrier. It is a two-engine tractor biplane that has been designed to give the specified normal speed with each engine throttled down to approximately half its output. Details of the landing gear, structural features, pilots' compartment, accommodation for mails, controls, power plant, and some flying qualities are provided.
The Caudron P.V. 200 Touring Airplane (French): An All-Metal Amphibian Monoplane
Circular presenting a description of the Caudron P.V. 200 touring amphibian, which is a two-place cantilever monoplane with folding wings and dual controls. Details of the wing, fuselage, controls, landing gear, flying qualities, and photographs are provided.
Charts for determining the pitching moment of tapered wings with sweepback and twist
From Summary: "This report presents a convenient method for calculating the pitching-moment characteristics of tapered wings with sweepback and twist. The method is based on the fact that the pitching-moment characteristics of a wing may be specified by giving the value of the pitching moment at zero lift and the location of the axis about which the axis is constant. Data for calculating these characteristics are presented by curves which apply to wings having a linear distribution of twist along the span and which cover a large range of aspect ratios. The curves are given for wings having straight taper and distorted elliptical plan forms. The characteristics of wings of other shapes may be determined by interpolation."
Comparison of Three Methods for Calculating the Compressive Strength of Flat and Slightly Curved Sheet and Stiffener Combinations
"This report gives a comparison of the accuracy of the three methods for calculating the compressive strength of flat sheet and stiffener combinations such as occur in stressed-skin or monocoque structures for aircraft. Of the three methods based upon various assumptions with regard to the interaction of sheet and stiffener, the method based upon mutual action of the stiffener and an effective width as a column gave the best agreement with the results of the tests. An investigation of the effect of small curvature resulted in the conclusion that the compressive strength of the curved panels is, for all practical purposes, equal to the strength of flat panels except for thick sheet where non-uniform curvature throughout the length may cause the strength of the curved panel to be 10 to 15 percent less than that of a corresponding flat panel" (p. 1).
The Comper "Mouse" Commercial Airplane (British): A Three-Seat Cabin Low-Wing Monoplane
Circular describing the Comper "Mouse" commercial airplane, which is a three-seat cabin low-wing monoplane. Details regarding the landing gear, wings, cabin, seating, fuselage, tail, power plant, controls, characteristics, performance, drawings, and photographs are provided.
A complete tank test of a model of a flying-boat hull - N.A.C.A. Model No. 11
"This note discusses the limitations of the conventional tank test of a seaplane model. The advantages of a complete test, giving the characteristics of the model at all speeds, loads, and trim angles in the useful range are pointed out. The data on N.A.C.A. Model No.11, obtained from a complete test, are presented and discussed. The results are analyzed to determine the best trim angle for each speed and load. The data for the best angles are reduced to non-dimensional form for ease of comparison and application. A practical problem using the characteristics of model no.11 is presented to show the method of calculating the take-off time and run of a seaplane from these data" (p. 1).
A Complete Tank Test of a Model of a Flying-Boat Hull - N.A.C.A. Model No.11
"This note discusses the limitations of the conventional tank test of a seaplane model. The advantages of a complete test, giving the characteristics of the model at all speeds, loads, and trim angles in the useful range are pointed out. The data on N.A.C.A. Model No.11, obtained from a complete test, are presented and discussed. The results are analyzed to determine the best trim angle for each speed and load. The data for the best angles are reduced to non-dimensional form for ease of comparison and application. A practical problem using the characteristics of model no.11 is presented to show the method of calculating the take-off time and run of a seaplane from these data" (p. 1).
A complete tank test of a model of a flying-boat Hull - N.A.C.A. model no.11-A
Model No. 11-A was designed as an improvement over N.A.C.A. Model No. 11, a complete test of which is described in N.A.C.A. Technical Note No. 464. In contrast with the longitudinal upward curvature in the planing bottom forward of the main step on Model 11-A was made as flat as practicable. Otherwise, the two models have very nearly the same form. The results of towing tests made on Model 11-A in the N.A.C.A. tank over a wide range of speed, load on the water, and trim angle are presented, both as original test data and as non dimensional coefficients. A comparison is made with similar results from the test of Model No. 11. The practical significance of the improvement obtained is demonstrated by applying the data from the new form to the illustrative design problem use in the note on Model NO. 11.
A Complete Tank Test of a Model of Flying-Boat Hull - N.A.C.A. Model 16
"A model of a 2-step flying-boat hull, of the type generally used in England, was tested according to the complete method described in the N.A.C.A. Technical Note No. 464. The lines of this model were taken from offsets given by Mr. William Munro in Flight, May 29, 1931. The data cover the range of loads, speeds, and trim angles that may be of use in applying the hull form to the design of any seaplane. The results are reduced to nondimensional form to aid application to design problems and facilitate comparison with the performance of other hulls" (p. 1).
The Critical Shear Load of Rectangular Plates
This report gives formulas for analyzing the critical shear load of a simply supported square, isotropic (simple flat plate), or orthogonal anisotropic plate (a plate in which the rigidity in two directions perpendicular to each other is different, i.e. plywood or corrugated sheet), these formulas, although arrived at by approximation method, seem to agree fairly well with experimental results.
The D.H. 85 "Leopard Moth" Airplane (British): A Three-Seat Cabin High-Wing Monoplane
Circular describing the De Havilland "Leopard Moth", which is a three-seat cabin high-wing monoplane with a good cruising speed and fuel efficiency. Details of the components, controls, characteristics, performance, drawings, and photographs are provided.
The d.h."Dragon Moth" Commercial Airplane (British): A Twin-Engine 6-Passenger Biplane
Circular presenting a description of the De Havilland Dragon Moth, or D.H. 84, which is the first twin-engine airplane built by this particular company. Details of the design, components, flight characteristics, performance, drawings, and photographs are provided.
The D.V.L. Gliding-Angle Control (W. Hübner Design)
This report describes a device for arbitrary enlargement of the gliding angle of airplanes, especially of such with flat gliding angle and difficult landing characteristics. The D.V.L. gliding angle control (design, Hubner) permits a local interruption of the lift distribution along the span and consequently an increased induced drag. The mechanism comprises two wing rudders operated by lever from the pilot's cockpit. Said rudders are fitted on the top side of the wing near the leading edge. The displacement of these rudders results in a separation of the air flow on the top side of the wing.
Determination of Inherent Stresses by Measuring Deformations of Drilled Holes
"Various methods have been proposed for determining the inherent stresses in structural components by disturbing their stress equilibrium through a mechanical device and measuring the resulting deformations. The methods used have disadvantages because they can be used only with specially shaped pieces (those with round or rectangular cross sections), that every form of test piece requires another kind of injury and hence of calculation, and the tested parts are rendered useless. The new test method, which seeks to eliminate these disadvantages, is likewise based on a disturbance of the equilibrium of forces, and indeed by drilling a hole which, however, is so small that the part can be used again" (p. 1).
Determination of the theoretical pressure distribution for twenty airfoils
This report gives the theoretical distribution of pressure at lift coefficients of 0, 0.5, 1.0, and 1.5 for 20 airfoils, calculated on the basis of a rigorous potential theory of arbitrary airfoils. It also provides tables from which the characteristics of the airfoils for any angle of attack in 2-dimensional potential flow are readily calculable. The theoretical values of the angles of zero lift, the lift and moment coefficients, and the ideal angles of attack are listed and some comparisons with experiment are indicated. The results presented may be of value in predicting structural loads and also in a correlation of theoretical pressure gradients with profile resistance.
Development of Air-Cooled Engines With Blower Cooling
With the aid of a heating device, the heat transfer to cylinders with conical fins of various forms is determined both for shrouded and exposed cylinders. Simultaneously the pressure drop for overcoming the resistance to the motion of air between the fins of the enclosed cylinder is measured. Thus the relations between the heat transfer and the energy required for cooling are discovered.
Development of the Rules Governing the Strength of Airplanes Part 1: German Loading Conditions Up to 1926
Load factors and loading conditions are presented for German aircraft. Loading conditions under various stress factors are presented along with a breakdown of individual aircraft components such as landing gear, wings, etc.
Development of the Rules Governing the Strength of Airplanes Part 2: Loading Conditions in Germany (Continued), England and the United States
Load factors and loading conditions are presented for Germany, England, and the United States. Results of tests are presented and loading conditions are presented under various stress categories like freight, commercial, aerobatics, and training.
Development of the Rules Governing the Strength of Airplanes Part 3: Loading Conditions in France, Italy, Holland, and Russia - Aims at Standardization
The historical development of the rules for structural strength of aircraft in the leading countries is traced from the beginning of flight to date. The term "factor of safety" is critically analyzed; its replacement by probability considerations has been considered desirable.
The Dewoitine D.332 Commercial Airplane (French): A Three-Engine All-Metal Low-Wing Monoplane
Circular describing the Dewoitine D.332, which is a commercial three-engine all-metal low-wing monoplane form France. Details of the construction history, wing, fuselage, power plant, landing gear, characteristics, performance, drawings, and photographs are provided.
The Dewoitine D.500 Pursuit Airplane (French): An All-Metal Cantilever Low-Wing Monoplane
Circular describing the Dewoitine D.500 pursuit airplane, which is an all-metal cantilever low-wing monoplane. Details of the fuselage, cockpit, control surfaces, weapons, landing gear, fuel tanks, wing, engine, characteristics, performances, drawings, and photographs are provided.
Dimensions of Twin Seaplane Floats
This paper presents the characteristics of floats submitted to the test committee and the tests performed on them.
The Drag of Streamline Wires
"Preliminary results are given of drag tests of streamline wires. Full-size wires were tested over a wide range of speeds in the N.A.C.A. high speed tunnel. The results are thus directly applicable to full-scale problems and include any compressibility effects encountered at the higher speeds. The results show how protuberances may be employed on conventional streamline wires to reduce the drag, and also show how the conventional wires compare with others having sections more like strut or symmetrical airfoil sections" (p. 1).
Dynamic Breaking Tests of Airplane Parts
"The static stresses of airplane parts, the magnitude of which can be determined with the aid of static load assumptions, are mostly superposed by dynamic stresses, the magnitude of which has been but little explored. The object of the present investigation is to show how the strength of airplane parts can best be tested with respect to dynamic stresses with and without superposed static loading, and to what extent the dynamic strength of the parts depends on their structural design. Experimental apparatus and evaluation methods were developed and tried for the execution of vibration-strength tests with entire structural parts both with and without superposed static loading" (p. 1).
The Effect of a Gap Between Elevator and Stabilizer on the Static Stability and Maneuverability About the Lateral Axis in Flight
"A number of German airplanes have a gap between elevator and stabilizer. The effect of this open space is not generally known, although English wind-tunnel experiments have shown that even a very small gap exerts a profound influence on the elevator action. The purpose of the present free-flight measurements is to ascertain whether fairing over the gap would actually result in an appreciable improvement" (p. 1).
Effect of aileron displacement on wing characteristics
The effect of aileron displacement on wing characteristics has been investigated for the Clark Y and the U.S.A. 27 wing sections equipped with rectangular ailerons. The airfoils, rectangular in plan, and having a 10 inch chord and 60 inch span, were mounted on a model fuselage.
The Effect of Partial-Span Split Flaps on the Aerodynamic Characteristics of a Clark Y Wing
"Aerodynamic force tests were made in the N.A.C.A. 7 by 10 foot wind tunnel on a model Clark Y wing with a 20 percent chord split flap deflected 60 degrees downward. The tests were made to determine the effect of partial-span split flaps, located at various positions along the wing span on the aerodynamic characteristics of the wing-and-flap combination. The different lengths and locations of the flaps were obtained by cutting off portions of a full-span flap, first from the tips and then from the center. The results are given in the form of curves of lift, drag, and center of pressure" (p. 1).
The Effect of Rivet Heads on the Characteristics of a 6 by 36 Foot Clark Y Metal Airfoil
"An investigation was conducted in the N.A.C.A. full-scale wind tunnel to determine the effects of exposed rivet heads on the aerodynamic characteristics of a metal-covered 6 by 36 foot Clark Y airfoil. Lead punching simulating 1/8 inch rivet heads were attached in full-span rows at a pitch of 1 inch at various chord positions. Tests were made at velocities varying from 40 to 120 miles per hour to investigate the scale effect" (p. 1).
The Effect of Split Trailing-Edge Wing Flaps on the Aerodynamic Characteristics of a Parasol Monoplane
"This paper presents the results of tests conducted in the N.A.C.A. full-scale wind tunnel on a Fairchild F-22 airplane equipped with a special wing having split trailing-edge flaps. The flaps extended over the outer 90 percent of the wing span, and were of the fixed-hinge type having a width equal to 20 percent of the wing chord. The results show that with a flap setting of 59 degrees the maximum lift of the wing was increased 42 percent, and that the flaps increased the range of available gliding angles from 2.7 degrees to 7.0 degrees" (p. 1).
The effect of spray strips on a model of the P3M-1 flying boat hull
This note presents the results of a series of tests made in the N.A.C.A. tank on a one-sixth full-size model of the hull and side floats of the Navy P3M-1 flying boat for the purpose of finding a method of reducing the amount of spray thrown into the propellers of this craft when taking off and landing. The model was tested without spray strips and with five different spray-strip arrangements. The best arrangement was an improvement over the bare hull with no spray strips, but the improvement was not sufficient to be satisfactory with the propellers in the designed position.
Effect of stabilizer location upon pitching and yawing moments in spins as shown by tests with the spinning balance
Tests were made with the spinning balance in a 5-foot wind tunnel to study the effect of stabilizer location upon the pitching and yawing moments given by the tail surfaces in spinning attitudes. The tests revealed that the horizontal surfaces, when in a normal location, seriously reduced the effectiveness of the fin and rudder, particularly at angles of attack of 50 degrees or more. The tests also revealed that a more forward or more rearward location gave no consistent or decided improvement; that a lower location greatly increased the shielding so that the yawing moment from the combination was in general less than that given by the bare fuselage; and that a higher location decreased the shielding and gave a favorable interference effect, particularly at the high angles of attack. Additional results regarding the stabilizer and the elevator are given.
Effect of Viscosity on Fuel Leakage Between Lapped Plungers and Sleeves and on the Discharge From a Pump-Injection System
"Test data and analysis show that the rate of fuel leakage between a lapped plunger and sleeve varies directly with the density of the fuel, the diameter of the plunger, the pressure producing the leakage, and the cube of the mean clearance between the plunger and sleeve. The rate varies inversely as the length of the lapped fit and the viscosity of the fuel. With a mean clearance between the plunger and sleeve of 0.0001 inch the leakage amounts to approximately 0.2 percent of the fuel injected with gasoline and as low as 0.01 percent with diesel fuel oils" (p. 63).
The Effect on Engine Performance of Change in Jacket-Water Outlet Temperature
Tests made on a Curtiss D-12 engine in the Altitude Laboratory at the Bureau of Standards show the following effects on engine performance of change in jacket-water outlet temperature: 1) Friction at all altitudes is a linear function of the jacket-water temperature, decreasing with increasing temperature. 2) The brake horsepower below an altitude of about 9,000 feet decreases, and at higher altitudes increases, with jacket-water temperature. 3) The brake specific fuel consumption tends to decrease, at all altitudes, with increasing jacket-water temperature. 4) The percentage change in brake power output is roughly equal to the algebraic sum of the percentage change in volumetric efficiency and mechanical efficiency.
The effect on lift, drag, and spinning characteristics of sharp leading edges on airplane wings
An investigation with special reference to auto rotation and spinning was conducted in two wind tunnels and in flight to find the aerodynamic effects of adding a sharp leading edge to a wing sector.
The effects of slots and flaps on lateral control of a low-wing monoplane as determined in flight
This paper presents the results of flight tests made to determine the effect of slots and flaps on the lateral control of a low-wing monoplane. Maximum angular accelerations in roll and yaw produced by sudden application of the ailerons and maximum accelerations in yaw produced by sudden application of the rudder during gliding flight were recorded for the following wing arrangements: (a) no auxiliary device; (b) full-span slots; (c) plain flaps; (d) flaps and full-span slots; (e) wing-tip slots. Rolling- and yawing-moment coefficients were derived from the accelerations.
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