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Viewing 19951 to 19980 of 19997
1917-01-01
Technical Paper
170001
V. E. CLARK, T. F. DODD, O. E. STRAHLMANN
The authors advance for discussion some important problems in the construction of airplanes for military use in this country. The functions of military airplanes designed for strategical and tactical reconnaissance, control of artillery fire and for pursuit are outlined. Problems in construction with reference to the two-propeller system, methods of reducing vibration, application of starting motors, details of the gasoline supply-system, metal construction for airplanes, flexible piping, desirable characteristics of mufflers, shock absorbers, landing gear, fire safety-devices, control of cooling-water temperature, variable camber wings, variable pitch propellers and propeller stresses, are all given consideration. The paper is concluded with suggestions for improvement in design relating to the use of bearing shims, the rigidity of crankcase castings, interchangeability of parts and better detail construction in the oiling, ignition, fuel supply and cooling systems.
1917-01-01
Technical Paper
170025
Amaury De La Grange
The author describes in a general way the three classes of battleplanes-the fighting, the reconnaisance and the bombing machines-and outlines the service for which each type is best fitted. The tests of engines and airplanes, prior to acceptance for the French Army, are cited. Among the difficulties of construction, those relating to the plane itself are relatively less serious than those relating to the engine. The greatest difficulty is to secure a reliable engine weighing only about 2 lb. per hp. The qualities of rotary and fixed-type engines are compared. The paper is concluded with a few remarks about aviators and mechanics and the relation of one to the other. The author has reserved some of his most interesting observations for the discussion, in which he describes vividly some actual airplane attacks and refers to night flying and night landing, concluding with suggestions as to “what America must do.”
1917-01-01
Technical Paper
170028
H. L. HORNING
The author first points out how increasing population and rising standards of living have increased the demand for foodstuffs and how such industrial activities as are brought about by the present conflict magnify the seriousness of the food problem, not only by withdrawing workers from the farms, but also by increasing food consumption on the part of those engaged in the speeded-up industries in order to supply the increased human energy required. The author then passes to a discussion of the tractor as a means for increasing the food supply by taking the place of withdrawn labor and cheapening production. Several charts show the effect of increased individual activity on food consumption, the relation of food consumption to standards of living and the growth of population, the variation of food demand during political activities during the past century, and the relation of the cost per calorie of various cereals.
1917-01-01
Technical Paper
170026
J. W. SEDDON
Starting with the statement that command of the air in warfare rests largely with the side that produces the best single-seater fighter, the author proceeds to outline some of the problems confronting the designer of fighting airplanes, and particularly the smaller ones. Considering better performance and better fighting qualities as the main desiderata, the author discusses means of obtaining them by: (1) increasing the horsepower-weight ratio; (2) decreasing the wing or structure resistances; (3) devising a new arrangement of the supporting planes, with regard to the position of pilot or crew, or by a combination of the above. Considerable space is devoted to methods of decreasing wing resistance, principally by employing low-resistance aerofoils, and the shaping of wing tips is also referred to.
1917-01-01
Technical Paper
170015
WALTER T. FISHLEIGH
1917-01-01
Technical Paper
170052
WALTER C. KEYS
After pointing out the existing dearth of easily workable data and formulas covering automobile suspensions, the author mentions the elements that contribute to riding comfort. He then outlines what he considers a good suspension, tabulating the spring dimensions of five hypothetical cars, typical of those on the American market. Curves of spring deflection are included in the paper. Functions of rear springs, the damping effect essential in good suspensions, “thin leaf” springs and spring lubrication are next discussed. In conclusion the author covers means of improving a car's riding qualities and cites a very interesting test for determining spring performance by means of the impressions made on a photographic plate by light from electric lamps mounted on wheels and fenders of an automobile and on the passengers.
1917-01-01
Technical Paper
170049
F. H. CRAVEN
After a few general introductory remarks the author outlines the operating requirements for tractors, and takes up the matter of the proper sizes of tractors, stated in horsepowers per given number of plows. The use of lower-grade fuels, value of water in the engine, cylinder construction, methods of lubrication and design of drive-wheels are the subjects covered by the balance of the paper.
1917-01-01
Technical Paper
170035
FRED P. STEELE
1917-01-01
Technical Paper
170032
DENT PARRETT
1917-01-01
Technical Paper
170033
H. C. Buffington
1917-01-01
Technical Paper
170039
ARNOLD P. YERKES
The author first considers the size of farm on which tractors can be used profitably. Confining his remarks to certain of the central and north central states, he points out the fact that there is a strong tendency for farms from 20 to 100 acres to be combined with others to make units of a more efficient size for the application of modern farming methods. Farms from 100 to 500 acres, representing 65 per cent of the total farm acreage, are the greatest users of tractors. Farms over 500 acres contain 25 per cent of the farm land, and also represent an important tractor market. Efficient sizes of tractors are next treated; three and four-plow sizes are generally preferred. Belt work, representing 50 per cent of a typical tractor's work, and other special duties performed by the tractor are next referred to.
1916-01-01
Technical Paper
160042
Frank E. Watts
The author confines his discussion to engines used on pleasure cars, inasmuch as practically all commercial vehicles use the four-cylinder type. The performance expected of their cars by automobile owners is outlined, particularly as regards performance, durability and maintenance cost. In-asmuch as the horsepower required is often determined by the acceleration demanded, the argument in favor of four-cylinder engines is based mainly on a comparison of its acceleration performance with those of engines having a larger number of cylinders. A number of acceleration curves are given for these engines. The paper next considers smoothness of operation at low, medium and high running speeds, asserting that the decrease in inertia forces due to lighter reciprocating parts has made it possible to increase the speed and thus reduce remarkably the vibration of the four-cylinder engine.
1916-01-01
Technical Paper
160033
Arthur J. Slade
The paper opens with a number of quotations from publications issued by the Army War College and showing the bearing of motor transport on a proper military policy for the United States. The author then describes two experimental trips recently made by motor-truck owners near New York in an effort to determine proper motor-transport operating conditions. A statistical summary is given for these two experimental trips. The Army War College has issued in compliance with instructions of the Secretary of War a “Statement of a Proper Military Policy for the United States,” supplemented by a number of pamphlets dealing with particular features of this military policy in considerable detail. In many of these supplementary pamphlets there appears a considerable amount of material bearing upon the subject of motor transport and from them the brief quotations in the following paragraphs are taken.
1916-01-01
Technical Paper
160034
C. M. EASON
Inasmuch as horses cannot meet the demand for increased farm power, the tractor must come at once. So far the supply of tractors has been entirely inadequate to meet the demand. The author specifiies some of the problems that confront designers of farm tractors. To make the tractor immediately available for farm work, it must be adaptable to practically all of the existing types of horse-drawn implements, besides furnishing belt power for a wide variety of present power-driven farm machinery. In designing tractors it must be remembered that the horse is a very flexible unit, capable of a wide variation in power output. Designing a tractor to furnish the necessary power for the majority of farm conditions, requires an intimate knowledge of crops, soils and farm management. These must be analyzed carefully so as to make the machine have as wide a range of usefulness as possible.
1916-01-01
Technical Paper
160032
W. F. BRADLEY
The author outlines the constructions that have performed cially that four-cylinder engines carried under a hood are the most satisfactory. The defects revealed by war service are given in considerable detail, the author finding that all of the trucks used had developed some weak point. Radiators and springs are specified as a general source of trouble. The author outlines a number of operating troubles developed under the existing conditions of operation and gives examples of the way these have been remedied. Considerable attention is paid to the methods of operating trucks away from made roads. The methods of fitting chains to the wheels, and the use of caterpillar attachments are described. Dimensions are given for bodies and a number of suggestions made as to their proper construction.
1916-01-01
Technical Paper
160009
J. G. VINCENT
1916-01-01
Technical Paper
160012
CHARLES S. CRAWFORD
1916-01-01
Technical Paper
160025
NEIL MACCOULL
The author gives a brief review of developments during the past year in the construction of aeroplanes, particularly as affected by the European War. He takes as an example the Renault twelve-cylinder engine, citing the respects in which the present differs from previous models. Such factors as the changes in cooling systems, method of drive, valve construction and starting devices are considered. The requirements of aeroplane engines, such as constant service, high speeds (of aeroplanes) and stream-line form of engines and radiators, are outlined. Propeller requirements are dealt with at length, curves being given by which the efficiency and diameter of the propeller can be obtained. In conclusion a number of different engine installations are illustrated and compared.
1916-01-01
Technical Paper
160020
D. L. GALLUP
The author points out the diversity of opinion on what constitutes desirable car performance in the minds of engineers and of the public generally. He believes this is largely due to the great diversity of claims which have been made in advertising literature and decries the sort of tests which have been made the basis of this publicity, pointing out that a majority of them are conducted under such conditions as make it practically impossible for the car owner ever to duplicate or confirm them. The kind of an expression or test which will inform the buying public most is one which will tell what the car will do in the hands of the average owner, and define the conditions under which a demonstration of this ability can be made, such conditions to be relatively simple and easy of fulfillment.
1916-01-01
Technical Paper
160017
L. GOLDMERSTEIN
1915-01-01
Technical Paper
150021
JOHN O. HEINZE
1915-01-01
Technical Paper
150040
JERRY W. DE COU
1915-01-01
Technical Paper
150039
FRANK H. TREGO
1914-01-01
Technical Paper
140049
FINLEY R. PORTER
1914-01-01
Technical Paper
140005
DAVID L. GALLUP
1914-01-01
Technical Paper
140032
CORNELIUS T. MYERS
1914-01-01
Technical Paper
140023
ALDEN L. McMURTRY
1914-01-01
Technical Paper
140016
JOSEPH A. ANGLADA
1913-01-01
Technical Paper
130031
CLAUDE E. COX
Viewing 19951 to 19980 of 19997