Engineering topics

Norton, F H

Publications and source records attributed to Norton, F H.

At least 19 records

NASA NTRS1925

Pressure Distribution over the Wings of an MB-3 Airplane in Flight

This investigation was carried out to determine the distribution of load over the wings of a high speed airplane under all conditions of flight. In particular it was desired to find the pressure distribution during level flight, over the portions of the wings in the slipstream and, during violent maneuvers, over the entire wing surface. The method used consisted in connecting a number of holes in the surface of the wings to recording multiple manometers mounted in the fuselage of the airplane. In this way simultaneous records could be taken on all of the holes for any desired length of time. (author)

Norton, F H↗

NASA NTRS1924

Complete Study of Longitudinal Oscillation of a VE-7 Airplane

This investigation was carried out by the National Advisory Committee for Aeronautics at Langley Field in order to study as closely as possible the behavior of an airplane when it was making a longitudinal oscillation. The airspeed, the altitude, the angle with the horizon and the angle of attack were all recorded simultaneously and the resulting curves plotted to the same time scale. The results show that all the curves are very close to damped sine curves, with the curves for height and angle of attack in phase, that for angle with the horizon leading them by 18 per cent and that for path angle leading them by 25 per cent.

Norton, F H↗

NASA NTRS1924

The Vertical, Longitudinal, and Lateral Accelerations Experienced by an S. E. 5a Airplane While Maneuvering

This investigation was carried out by the Langley Field Laboratory of the National Advisory Committee for Aeronautics for the purpose of measuring the accelerations along the three principal axes of an airplane while it was maneuvering. The airplane selected for this purpose was the fairly maneuverable SE-5A and the instruments used were the NACA three component accelerometer and the NACA recording airspeed meter. The results showed that the normal accelerations did not exceed 4.000 G. While the lateral and longitudinal accelerations did not exceed 0.60 G.

Norton, F H↗

NASA NTRS1924

The Measurement of the Damping in Roll on a Jn4h in Flight

This investigation was carried out by the National Advisory Committee for Aeronautics for the purpose of measuring the value of L sub P in flight. The method consisted in flying with heavy weights on each wing tip, suddenly releasing one of them, and allowing the airplane to roll up to 90 degrees with controls held in neutral while a record was being taken of the airspeed, and angular velocity about the X axis. The results are of interest as they show that the damping found in the wind tunnel by the method of small oscillations is in general 40 per cent higher than the damping in flight. At 50 M. P. H. The flight curve of L sub P has a high peak, which is not indicated in the model results. It is also shown that at this speed the lateral maneuverability is low.

Norton, F H↗

NASA NTRS1924

A study of longitudinal dynamic stability in flight

This investigation was carried out by the aerodynamic staff of the National Advisory Committee for Aeronautics for the purpose of studying experimentally the longitudinal dynamic stability of airplanes in flight. The airplanes selected for this purpose were a standard rigged VE-7 advanced-training airplane and a JN4H with special tail surfaces. The airplanes were caused to oscillate by means of the elevator, then the longitudinal control was either locked or kept free while the oscillation died out. The magnitude of the oscillation was recorded either by a kymograph or an airspeed meter. The results show that the engine speed has as much effect on the period and damping as the airspeed, and that, contrary to theory as developed for small oscillations, the damping decreased at the higher airspeeds with closed throttle.

Norton, F H↗

NASA NTRS1924

The Small Angular Oscillations of Airplanes in Steady Flight

This investigation was carried out by the National Advisory Committee for Aeronautics at the request of the Army Air Service to provide data concerning the small angular oscillations of several types of airplanes in steady flight under various atmospheric conditions. The data are of use in the design of bomb sights and other aircraft instruments. The method used consisted in flying the airplane steadily in one direction for at least one minute, while recording the angle of the airplane with the sun by means of a kymograph. The results show that the oscillations differ but little for airplanes of various types, but that the condition of the atmosphere is an important factor. The average angular excursion from the mean in smooth air is 0.8 degrees in pitch, 1.4 degrees in roll, and 0.9 degrees in yaw, without special instruments to aid the pilot in holding steady conditions. In bumpy air the values given above are increased about 50 per cent. (author)

Norton, F H↗

NASA NTRS1923

Control in Circling Flight

This investigation was undertaken for the purpose of developing instruments that would record the forces and positions of all three controls, and to obtain data on the behavior of an airplane in turns. All the work was done on a standard rigged JN4H (airplane no. 2 of National Advisory Committee for Aeronautics, report no. 70). It was found that the airplane was longitudinally unstable and nose heavy; that it was laterally unstable, probably due to too little dihedral; and that it was directionally unstable, due to insufficient fin area, this last being very serious, for in case of a loss of rudder control the airplane immediately whips into a spin from which there is no way of getting it out. On the other hand, it was found possible to fly quite satisfactorily with the rudder locked, and safely, though not so well, with the ailerons locked.

Norton, F H↗

NASA NTRS1923

The Pressure Distribution Over the Horizontal Tail Surfaces of an Airplane I

This work was undertaken to determine as completely as possible the distribution of pressure over the horizontal tail surfaces of an airplane, and to analyze the relation of this pressure to the structural loads and the longitudinal stability. The investigation is divided into three parts, of which this the first. The first part of the investigation is for the purpose of determining the pressure distribution over two horizontal tail surfaces in uniform free flight; the second part to conduct tests of similar tail planes in the wind tunnel; and the third part to determine the pressure distribution on the horizontal tail surfaces during accelerated flight on the full-size airplane.

Norton, F H↗

NASA NTRS1923

Practical stability and controllability of airplanes

The effect of the characteristics of an airplane on balance, stability, and controllability, based on free flight tests, is discussed particularly in respect to the longitudinal motion. It is shown that the amount of longitudinal stability can be varied by changing the position of the center of gravity or by varying the aspect ratio of the tail plane, and that the stability for any particular air speed can be varied by changing the camber of the tail plane. It is found that complete longitudinal stability may be obtained even when the tail plane is at all times a lifting surface. Empirical values are given for the characteristics of a new airplane for producing any desired amount of stability and control, or to correct the faults of an airplane already constructed. (author)

Norton, F H↗

NASA NTRS1923

The Pressure Distribution over the Horizontal Tail Surfaces of an Airplane III

This report contains the results of an investigation of the distribution of pressure over the tail surfaces of a full-sized airplane during accelerated flight for the purpose of determining the magnitude of the tail and fuselage stresses in maneuvering. As the pressures in accelerated flight change in value with great rapidity, it was found that the liquid manometer used in the first part of this investigation would not be at all suitable under these conditions; so it was necessary to design and construct a new manometer containing a large number of recording diaphragm gauges for these measurements. Sixty openings on the tail surfaces were connected to this manometer and continuous records of pressures for each pair of holes were taken during various maneuvers. There were also recorded, simultaneously with the pressures, the normal acceleration at the center of gravity and the angular position of all the controls. The present investigation consisted in measuring on a standard rigged JN4H airplane the distribution of pressure over the whole of the horizontal tail surfaces while the airplane was being put through maneuvers as violently as it was thought safe, including spinning and pulling out of dives.

Norton, F H↗

NASA NTRS1923

Pressure Distribution over the Rudder and Fin of an Airplane in Flight

This investigation was carried out by the National Advisory Committee for Aeronautics at the Langley Memorial Aeronautical Laboratory for the purpose of determining the loads which occur on the vertical tail surfaces in flight. The method consisted in measuring the pressures simultaneously at 28 points on the rudder and fin by means of a recording multiple manometer. The results show that the maximum load encountered in stunting was 7 pounds per square foot on the rudder and fin, and it is probable that this might rise to 10 pounds per square foot in a violent barrel roll; but in steady flight the average loads do not exceed 0.6 pound per square foot. The maximum load on the rudder and fin may occur at the same instant as the maximum load on the horizontal tail surfaces and the maximum normal acceleration. The torsional moment about the axis of the fuselage due to the rudder and fin may rise as high as 250 foot-pound. The results obtained from this investigation have a direct application to the design of the rudder, fin, and fuselage.

Norton, F H↗

NASA NTRS1923

Pressure Distribution over Thick Airfoils - Model Tests

This investigation was undertaken to study the distribution of loading over thick wings of various types. The unloading on the wing was determined by taking the pressure at a number of holes on both the upper and lower surfaces of a model wing in the wind tunnel. The results from these tests show, first, that the distribution of pressure over a thick wing of uniform section is very little different from that over a thin wing; second, that wings tapering either in chord or thickness have the lateral center of pressure, as would be expected, slightly nearer the center of the wings; and, third, that wings tapering in plan form and with a section everywhere proportional to the center section may be considered to have a loading at any point which is proportional to the chord when compared to a wing with a similar constant section. These tests confirm the belief that wings tapering both in thickness and plan form are of considerable structural value because the lateral center of pressure is thereby moved toward the center of the span.

Norton, F H↗

NASA NTRS1923

Aerodynamic properties of thick airfoils II

This investigation is an extension of NACA report no. 75 for the purpose of studying the effect of various modifications in a given wing section, including changes in thickness, height of lower camber, taper in thickness, and taper in plan form with special reference to the development of thick, efficient airfoils. The method consisted in testing the wings in the NACA 5-foot wind tunnel at speeds up to 50 meters (164 feet) per second while they were being supported on a new type of wire balance. Some of the airfoils developed showed results of great promise. For example, one wing (no. 81) with a thickness in the center of 4.5 times that of the U. S. A. 16 showed both uniformly high efficiency and a higher maximum lift than this excellent section. These thick sections will be especially useful on airplanes with cantilever construction. (author)

Norton, F H↗

NASA NTRS1923

Controllability and Maneuverability of Airplanes

This investigation was conducted for the purpose of studying the behavior of the JN4H airplane in free flight under the action of its controls and from this to arrive at satisfactory definitions and coefficients for controllability and maneuverability. The method consisted in recording the angular velocity about the three axes, together with the air speed, control positions, and acceleration. (author)

Norton, F H↗

NASA NTRS1922

A Preliminary Study of Airplane Performance

Flight tests were carried out at the Langley Field laboratory of the NACA, on several airplanes for the purpose of determining their relative performance with the same engine and the same propeller. The method used consisted in flying each airplane on a level course and measuring the airspeed for the whole range of engine revolutions. In general the results show that a small change in the wing section or the wing area has but a slight effect upon the performance, but changes in those parts which cause the structural resistance have a very important effect.

Norton, F H↗

NASA NTRS1922

The Effect of Longitudinal Moment of Inertia upon Dynamic Stability

Free flight tests were carried out to show whether the longitudinal oscillations of a standard S.E.5A airplane are noticeably affected if its longitudinal moment of inertia is increased. These oscillations were taken by means of a self-recording instrument, the airplane having first its ordinary moment of inertia and then one increased by 14 percent. The period of oscillation was slightly longer after the increase of the moment of inertia, but the damping was not affected. Presented here are test results from an investigation to determine the relative performance of a single-cylinder, high-speed, compression-ignition engine when using fuel injection valve nozzles with different numbers, sizes, and directions of round orifices. A spring loaded, automatic injection valve was used. It was centrally located at the top of a vertical disk-type combustion chamber formed between horizontally opposed inlet and exhaust valves of a 5-inch by 7-inch engine. A series of fuel injection valve nozzles with different arrangements of round orifices were tested, starting with orifices so small that impingement on the combustion chamber walls was impossible and increasing beyond the start of impingement. a :A table and curves are presented showing the performance of the engine with different nozzles. The test results are discussed, and some probable reasons given for the variation in performance with different nozzles on the basis of spray distribution.

MOMENTS OF INERTIA - ROYAL AIRCRAFT FACTORY S E 5A↗

NASA NTRS1922

N.A.C.A. Control Position Recorder

A new instrument is described which is capable of simultaneously recording the position of the three controls of an airplane. The records are taken photographically on a standard N.A.C.A. film drum and the instrument can be quickly installed in any airplane.

Norton, F H↗

NASA NTRS1922

A Preliminary Investigation of a New Method for Testing Aerofoils in Free Flight

This report is a description of a new method of testing aerofoils in free flight devised by the National Advisory Committee for Aeronautics. The method consists in lowering below a flying airplane a large inverted aerofoil on three small steel wires in such a way that the lift on the aerofoil always keeps the wires tight. The resultant force is measured by the tension in the wires, and the direction of the resultant by the amount the wing trails backwards. A test was made on an aerofoil of the N.A.C.A. #64 section, 6 ft. in span and the results are compared with a similar section tested in the wind tunnel. This investigation indicates that by the use of suitable recording apparatus aerofoils may be accurately and conveniently tested at a Reynolds number, a velocity and a degree of turbulence, comparable with that on the full-sized airplane. Satisfactory experiments were also made in trailing a sphere and a streamlined body on single wires.

Norton, F H↗