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Viewing 16501 to 16530 of 16574
1938-01-01
Technical Paper
380093
R. P. Lansing, C. I. MacNeil
1938-01-01
Technical Paper
380028
G. L. Davies
1937-01-01
Technical Paper
370165
R. M. Critchfield
1937-01-01
Technical Paper
370127
E. Martin, C. F. Baker
THE development work that resulted in the Hamilton standard constant-speed control is discussed briefly, and the various types of controls that were evolved during the development are described. The present control is described in detail both as to the design characteristics and the operation in conjunction with the propeller. The design requirements of the governing principle employed are discussed briefly.
1937-01-01
Technical Paper
370025
Sidney Oldberg, Maynard Yeasting, Max M. Roensch
1937-01-01
Technical Paper
370037
Melville F. Peters, George F. Blackburn, Paul T. Hannen
1936-01-01
Technical Paper
360146
R. A. Rose, G. C. Wilson, R. R. Benedict
SOLUTION of the problem of igniting and burning the fuel in the high-speed Diesel engine profoundly affects its development, according to the authors. This paper describes the photo-electric set-up selected to indicate the behavior of the fuel in the combustion-chamber because of its high speed, its intensity, its zero time lag, and its freedom from inertia effects. A magnetic-type oscillograph for recording the impulses, a cantilever-spring indicator for picking up the pressure impulse, and an amplifier between the photo-cell and the oscillograph, comprise the principal parts of this instrumentation, as applied to a single-cylinder test engine. Results of tests with a three-beam vibrator-type oscillograph are given with oscillograms for different fuels, loads, and injection angles. Other tests are described using a cathode-ray oscillograph and a high-speed camera.
1936-01-01
Technical Paper
360150
E. M. Dodds
THIS paper describes a number of applications of the cathode-ray tube to the solution of engine problems, such as indication of pressures in the cylinder and in Diesel fuel lines; mechanical vibration of moving parts; torsional oscillations of shafts; whip of shafts; and time of arrival and duration of flame at any point in the cylinder-head. The different technique involved when hard-vacuum cathode-ray tubes are used instead of the gas-filled variety, is also indicated. An outline is given of some of the work rendered possible by its aid. This includes observations on the nature of the octane scale in so far as its relation to combustion pressure is concerned. A contribution is made to the theory of the mechanism of Diesel knock intensity together with some information on improving the power output and cleanliness of running of a C.F.R.-Pope Diesel engine.
1936-01-01
Technical Paper
360040
ALLAN A. BARRIE
1936-01-01
Technical Paper
360113
Fred E. Weick
THIS paper contains the results of a modest attempt that has been in progress for the past few years to develop certain characteristics in airplanes that would make them better suited to general private use. A two-place pusher monoplane, the W-1, was constructed as part of this program, and later, with the aid of the Bureau of Air Commerce, was modified to include special flaps and special ailerons. The distinctive technical features fall into four main divisions, the first discussing the landing-gear arrangement. A stable three-wheel landing-gear was used that eliminates many of the present landing, take-off, and ground-handling difficulties. The second division deals with means for obtaining lateral stability and control at low speeds, with freedom from the dangers of the stall. The third takes up a flap arrangement for obtaining direct and immediate control of the glide-path angle to facilitate landing steeply at the exact point desired.
1935-01-01
Technical Paper
350090
Fred L. Faulkner
Summary THE Subcommittee on Motor-Vehicle Design from the operation and maintenance standpoint was instructed to continue its studies and prepare a short summary for the 1935 Annual Meeting. In discussing the possible subject matter with the Committee, so many phases of this subject were questioned that it was impossible in a short space of time to give them full consideration in time for this presentation. I have therefore limited the report to cover mainly the electrical group and the highly controversial subject of motor-truck ratings. The largest number of complaints and the most severe criticisms on the electrical group come from fleet operators in the so-called low-temperature area. Winter starting-difficulties are prevalent, not only on account of inadequate storage batteries and starting motors but inefficient generators as well. Likewise, this problem is all tied in with the much discussed problem of winter grades of crankcase lubricating oil.
1934-01-01
Technical Paper
340016
T. P. Wright
In this paper, the author has first shown the increasing need, amounting in many instances to a necessity, for the adoption of the controllable pitch propeller on modern airplanes. Improvements in airplane design which bring about increased speed range have brought about a decrease in other performance items which can only be rectified by the use of the controllable pitch propeller. The improvement has been shown to be so great as to well pay for the added complication and expense involved. The several types of controllable pitch propeller developed in this country are described, the author going into considerable detail on the electric-driven type. The numerous test requirements are gone into in detail. In conclusion, the author notes greater progress in the development of the controllable pitch propeller in this country than elsewhere, perhaps necessitated by the accompanying advance in aerodynamic refinements here developed.
1934-01-01
Technical Paper
340010
W. M. Johnson
1934-01-01
Technical Paper
340015
G. T. Lampton
1934-01-01
Technical Paper
340025
J. T. Fitzsimmons
1934-01-01
Technical Paper
340024
R. P. Lansing
1934-01-01
Technical Paper
340070
LOUIS WAIT
1933-01-01
Technical Paper
330011
E. E. Wemp
Summary FIRST consideration is given by the author to basic improvements in clutches of the lever-release single-plate and to those of the two-plate types. He emphasizes that the severity of clutch service has increased very materially in the last few years and that the increased clutch duty of today is further augmented by the car manufacturer in providing cars having greater acceleration and higher torque, particularly at the higher speeds and usually without a proportionate increase in clutch size. Developments along logical lines which have resulted in improvements in design are cited as being (a) the design of the driven disc and the selection of facings, to produce improved engagement and greater life; (b) design of the cover-plate assembly to permit higher spring pressure with less retracting movement of the pressure plate; and better selection of facing and pressure-plate materials to reduce facing wear and pressure-plate distortion or scoring.
1933-01-01
Technical Paper
330003
A. L. MacClain, D. S. Hersey
THE purpose of this paper is to show that the value of commercial flight-testing depends largely upon the utility, reliability and accuracy of the equipment and instruments employed. In general, it is found that improvements in these three factors depend largely on the simplicity of the apparatus used. Special engine-tests have led to the development of instruments and apparatus not commonly available commercially, and the use of these has made it possible to employ the aircraft engine as an instrument for the measurement of power in flight. This ability to measure power has led to the development of a method of making comparative engine-temperature and other tests which eliminates or corrects for a number of the major variables ordinarily affecting such tests. Because of the increasing popularity of the controllable-angle propeller, tests are also described which enable one to determine the value of such a propeller when only an adjustable-angle propeller is available.
1932-01-01
Technical Paper
320036
D. A. Dickey, O. R. Cook
THE DEMAND for a successful controllable or automatic propeller is greater today than ever. Such a propeller will enable commercial aircraft to take off safely with greater loads, and it may enable multi-engine airplanes that cannot now maintain altitude with one engine dead to do so with a safe margin of power. For military aircraft it means increased rate of climb and increased speed at altitude, especially with supercharged engines. To obviate confusion in nomenclature, the authors give definitions of adjustable, controllable and automatic propellers. Distinction is drawn between the needs of different classes of airplane for different types of changeable-pitch propellers. Many propellers falling within the several classes have been designed but few are in use. Cost, weight and complication are obstacles to their commercial success. Several problems still confront the designer in this field, the chief one being that of obtaining material that is sufficiently light and strong.
1932-01-01
Technical Paper
320042
Harold Gatty
HEREIN the author describes methods and shows instruments, tables, scales and curves used for air navigation. The ground-speed-and-drift meter devised by him and used with such remarkable success in the round-the-world flight with Wiley Post in less than nine days, on which the author was navigator, is illustrated and described. Much has been accomplished in the last few years in providing methods and equipment for quickly and accurately determining the position and laying the correct course of aircraft, but considerable improvement remains to be made in instruments, particularly sextants. No one method of navigation can be used under all conditions; a combination of four is necessary to achieve the best results.
1932-01-01
Technical Paper
320043
Ralph H. Upson
BLIND flying without special training, together with general improvement in flight control, is possible with a new simplified type of artificial horizon. The instrument in most respects provides a safer reference for control than does the natural horizon, because it deals directly with the real source of control, which is the air. Air is to the airplane as the road to an automobile; the different movements of the airplane relative to its own road of air primarily determine its control. To make such movements visible is a function of instruments, but a set of several different instruments to show separate movements of the airplane is unnecessarily complicated and expensive. A single instrument giving the unity and simplicity of the natural horizon but having a directness of reading that can be obtained only from the directly adjacent air is the remedy.
1931-01-01
Technical Paper
310036
Stephen J. Zand
AIRPLANE vibration produces many undesirable conditions during flight, such as fatigue of structural members, a bad effect on the nervous systems of the occupants and the like. Excessive vibration leads to premature deterioration or to erroneous indications of instruments. Vibrations can be analyzed from a mathematical viewpoint with gratifying results, but such analysis is sometimes difficult and often is applicable only to selected conditions. A serious mathematical analysis was carried out in the investigation of resonance conditions between engine and engine mount. Then the problem was approached from a rather empirical viewpoint to give vibration relations, not, as heretofore, to bodily sensation, but to such terms as amplitude, frequency, the relation between the two, form and the like.
1929-01-01
Technical Paper
290061
T. P. WRIGHT, W. R. TURNBULL
1929-01-01
Technical Paper
290049
MICHAEL WATTER
THE causes and nature of the spinning of an airplane, and measures for the prevention of and recovery from a spin, are discussed. Tests and analysis are said to have shown that spinning is a stable motion of rotation, and that the real dangers are in its instability. Recovery from a spin is held to be more important than prevention, as complete knowledge of means of recovery will lead to mastery of the whole phenomenon. The spinning motion is a combination and balance of aerodynamic and purely dynamic forces and couples, asserts the author. Full-scale experiments prove beyond doubt that side-slip may be very pronounced in a spin, which changes considerably the rate of roll of the simple autorotational kind. The rolling of the wings leads to the establishing of a yawning couple which may become dangerous, tending to keep the craft in a spin because of the increased shielding of the tail surfaces.
1928-01-01
Technical Paper
280018
JOHN SNEED
THE theory and characteristics of brakes of the Steeldraulic system are set forth and their application in practice is explained. Self-energizing brakes are said to be desirable because they allow large clearances, low pedal-effort and frictional coefficient and, if properly designed, give a high degree of efficiency with smooth uniform action. To accomplish these results, the controls should deliver equal and accurate actuation to all brakes at all times, be designed to minimize the possibility of becoming inoperative on account of dirt and rust, require no servicing, be noiseless and of good appearance, and remain unaffected by climatic changes. Shoe design should allow very liberal limits and tolerances in wheel, axle and drum assemblies, without causing erratic brake-action or noises. The brake hook-up should follow the simplest line and use the least number of connecting links.
1928-01-01
Technical Paper
280019
NEWTON F. HADLEY
AN effort is made to determine the essentials of an ideal shock-absorber and to describe the types that approach or depart from this ideal. Mathematical analysis is not used, but judgment is based on the experience of the author with various types. The requirements of a satisfactory shock-absorber are defined and the methods used by the author in culling out certain shock-absorbers that fail to meet these requirements are outlined. By means of a machine based on the principle, of a steam-engine indicator, the energy required to move a shock-absorber throughout its cycle at varying speeds is measured and charts are obtained. When these charts are compared with a characteristic shape of diagram of a shock-absorber found from repeated trials on the road to give the most satisfactory riding, the merits or shortcomings of any other shock-absorber can be deduced from the difference in shape.
1927-01-01
Technical Paper
270001
C. S. CRAGOE, J. O. EISINGER
PREVIOUS papers relating to the cooperative fuel-research investigation of engine-starting have attacked the problem along two distinct lines, namely, (a) by actual tests of the time required to start engines under various conditions, such as temperature, mixture supplied and the like, using different fuels; and (b) by laboratory tests of the volatility of the same fuels under somewhat similar conditions, using the method of equilibrium air-distillation. In this paper the results of these two methods of attack are correlated. For this purpose, it was necessary to extend the air-distillation data to lower temperatures than had been used in the tests. This involved an application of the laws of the perfect gas and the well-established law governing the relation between vapor pressure and temperature. The results of the engine tests were originally plotted with the rate of fuel supplied, as ordinate, and the time required to start, as abscissa.
1927-01-01
Technical Paper
270002
G. L. CLARK, A. L. HENNE
DETAILS are given of the method of control of the engine so that quantitative and reproducible measurements of detonation and comparisons with spectra can be made. Typical data are tabulated and photographs are shown of the free-burning flames of hydrogen, carbon monoxide, methane, gasoline in a blow-torch, and the like. The spectra of explosion and of detonation in the engine confirm earlier conclusions. By means of a synchronous shutter, the spectra of radiation during the four quarters of a stroke are obtained for straight-run gasoline under detonating and non-detonating conditions for the same fuel containing tetraethyl lead, aniline and iodine as knock suppressers and for cracked-gasoline blends. The outstanding result is that, during detonation, the first-quarter spectrum extends far into the ultra-violet, that of the second quarter, a somewhat less distance; the third and fourth quarters are characterized by very little radiation energy.
1927-01-01
Technical Paper
270074
A. F. HEGENBERGER, BRADLEY JONES
Viewing 16501 to 16530 of 16574