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Viewing 16441 to 16470 of 16558
1946-01-01
Technical Paper
460097
Alfred J. Poole
1946-01-01
Technical Paper
460013
J. B. Hiday
1945-01-01
Technical Paper
450203
Duncan B. Gardiner
AIRPLANE hydraulic braking systems must be designed to have the highest standard of performance without sacrificing reliability. By the use of a multielement oscillograph the various characteristics of the braking system can be recorded simultaneously so that the value of design changes can easily be determined. Oscillograms for a typical aircraft braking system show that relatively minor changes result in a wide differential in performance and emphasize the conclusion that design changes in a hydraulic brake system should be evaluated with the oscillograph.
1945-01-01
Technical Paper
450165
E. G. RILEY
THE need for power boost controls, as evidenced by the practical limitations experienced with mechanical types of manual-assist control methods, is briefly summarized. This is followed by an analysis of power boost control in general in so far as location of major elements is concerned. Also included is an analysis of the conditions under which power boost is required and a list of basic characteristics which are essential as a design nucleus. Each characteristic is presented in detail and reasons for its inclusion are explained. A complete description of the principles of operation of the Vickers hydraulic boost control as used on the Martin Mars is presented with a schematic diagram of a typical control system incorporating the boost unit. Selection of power source and all related hydraulic and mechanical equipment necessary for satisfactory operation of the Vickers unit is described.
1945-01-01
Technical Paper
450079
R. J. Lusk
1945-01-01
Technical Paper
450071
E. J. McLaughlin
1945-01-01
Technical Paper
450026
H. E. Gulbransen
1945-01-01
Technical Paper
450022
R. J. Colin
1945-01-01
Technical Paper
450003
M. F. Vanik
1945-01-01
Technical Paper
450044
Austin F. Trumbull
Synopsis An actual detailed aircraft electrical load analysis is a chore for an ‘IBM’ machine, and is indicative only of a specific airplane under controlled conditions. This paper concerns itself with the problem qualitatively, and attempts to show the trend and the advantages of a single Auxiliary Power System for Aircraft, that single system being the electrical system, and into what magnitude of electrical loads such thinking may lead us.
1945-01-01
Technical Paper
450041
Harold W. Adams, Fred Foulon
1944-01-01
Technical Paper
440154
W. C. TRAUTMAN, R. E. MIDDLETON
HYDRAULIC systems have the advantage of lighter weight, particularly in the higher horsepowers, when compared with electrical systems, although both systems should maintain their rightful places in aircraft, to be used where they can contribute most to the efficiency of the airplane as a whole. These conclusions have been reached by the authors of this paper, after having made comparisons on the following bases: 1. A comparison of the individual components of each system on the basis of weight in pounds per horsepower at various horsepower ratings and at efficiencies that are commonly used in aircraft practice. 2. A comparison of typical hydraulic and electrical accessory power transmission systems designed to perform an identical job on a modern airplane. This study has been confined to 28-v, d-c electrical systems and 1500-psi hydraulic systems.
1944-01-01
Technical Paper
440206
C. E. GRINSTEAD, R. N. FRAWLEY, F. W. CHAPMAN, H. F. SCHULTZ
THE principle of operation and the mechanical design of an improved indicator for measuring static and dynamic pressures are discussed in this paper. The condenser type of indicator was selected by the authors for engine work because it lends itself to an exceptionally compact and sturdy construction, it is easily serviced, it has a high natural frequency, and it is relatively insensitive to shock and vibration. This type of indicator also does not require mechanical linkage between the pressure diaphragm and the electrically sensitive element.
1944-01-01
Technical Paper
440092
W. A. Reichel
1944-01-01
Technical Paper
440097
E. F. Burton, Carlos Wood
ABSTRACT
1944-01-01
Technical Paper
440043
George A. Bleyle
1944-01-01
Technical Paper
440054
R. L. Ellinger
1944-01-01
Technical Paper
440215
J. S. DECKER
1944-01-01
Technical Paper
440217
John H. Little
1943-01-01
Technical Paper
430077
James B. Kendrick
1943-01-01
Technical Paper
430132
JOHN H. LITTLE, ROBERT A. DAILY
PLENTY of heat is the best solution to the problems encountered in using storage batteries at low temperatures, the authors say. Starting at low temperatures is difficult for two reasons. A cold engine requires higher torque to start it, and the colder the battery the less the amount of current that can be drawn from it. With a 24-v battery, an engine requires to start it at a certain temperature only one-fourth the amount of current it would require if the battery were only 6 v. After an engine has been started, it is necessary to put back the energy taken out plus a little more because battery charging is not 100% efficient. This cannot be done at low temperatures. For efficient charging, the battery temperature should be at least 40 F. For batteries that are used fairly frequently, it is helpful to keep them in well-insulated boxes, or in boxes that have had a piping system rigged up so that warm water can be circulated through the boxes.
1943-01-01
Technical Paper
430146
H. L. KNUDSEN
THE inescapable conclusion of Mr. Knudsen is that an immersion heater is required for the starting of diesel engines at subzero temperatures. “With this method,” he says, “the danger of scoring and scuffing pistons and cylinders during the cranking period due to improper oil films is removed. The engine can be started with the lubricating oil most suitable for it at operating temperature. Cranking power requirements are no greater than in the summertime, so the batteries need not be excessively large for winter starting - even the batteries might be kept up to temperature by an immersion heater, and hence a further reduction in weight and capacity would be possible.” Mr. Knudsen resolves the problem of subzero starting into several parts: 1. The fuel oil must be able to flow freely at starting temperatures. 2. Lubricating oil must be available that permits cranking at about 100 rpm at the desired starting temperature with reasonable starting-power requirements. 3.
1943-01-01
Technical Paper
430055
W. P. Lear
1943-01-01
Technical Paper
430052
J. W. Kelly
1942-01-01
Technical Paper
420068
Kalman J. DeJuhasz
1942-01-01
Technical Paper
420074
John D. Waugh
1941-01-01
Technical Paper
410101
P. C. SANDRETTO
THIS paper shows that the growth of electrical demands on planes is due mainly to the problems encountered in operating the planes and, hence, electrical systems are the chief concern of the plane operators. Existing electrical systems are discussed from the standpoint of the operator, under the headings of “trouble,” “weight,” and “facilities.” A new system is described for the plane of the future, which is assumed to have a gross weight of about 100,000 lb, and a power demand of 30 kw. By means of variable-frequency systems a considerable weight saving is forecast.
1941-01-01
Technical Paper
410096
NATHAN C. PRICE
COMPARISONS are drawn, in this paper, between engine supercharger and cabin supercharger flow-control problems. Some new methods of obtaining efficient flow control are discussed. Interdependent factors existing between flow control and impeller speed control must be recognized. It is pointed out that design features in the supercharger should be correlated closely with the type of control applied. Effects arising from the connection of superchargers to receivers of large volume are presented. Necessity for regulation of flow, pressure, and rate of pressure change in pressure cabins requires the solution of numerous new problems. The advantage of simultaneous design of the supercharger and controls, and the desirability of integral supercharger and control units, are stressed. It has been necessary to overcome many mechanical problems in order to produce units of a type suited for pressure cabin operation. Typical control constructions are described.
1941-01-01
Technical Paper
410134
W. G. AINSLEY
THE CFR Full-Scale Engine Group was organized by engine men representing the major classifications of automotive-type diesel engines. This original group, with the cooperation of the representatives of the petroleum industry, the government agencies, and colleges, has carried on extensive series of tests on commercial diesel engines. The purpose of the investigation was to determine the influence of fuel properties such as cetane number, viscosity, volatility, and gravity on the engine performance. The following relationships are indicated: Starting and engine smoothness are dependent upon the ignition quality of the fuel. Smoke and engine deposits vary with the volatility and viscosity. Exhaust odor varies with ignition quality and cetane number. Power output and fuel consumption vary with the heat value of the fuel. At a given pump setting, viscosity may have an independent effect on the power output because of plunger leakage.
Viewing 16441 to 16470 of 16558