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THE main purpose of this paper is to illustrate the results or effects of water and water-alcohol injection on aircraft-engine performance. Water offers the best rate of cooling at high power output and, the authors point out, should be used without any additive where cooling is of paramount importance. Water-methanol mixtures, on the other hand, they explain, will afford the most increase in power output normally limited by destructive detonation. Because of the increased flexibility possible with the use of such fluids, military installations have already taken advantage of them, and commercial operators will want to study the problem thoroughly to determine how their use will fit into the postwar plan of operations.

IF the refiner is to succeed in blending good, low-cost aircraft fuels from the hundreds of components now available to him, these authors point out that it will be necessary for the aircraft and oil industries to cooperate in determining actual fuel performance requirements. To help reach this goal, the authors present here an extensive discussion of the factors affecting the performance of the fuel-engine combination; namely, power, economy, and reliability (including safety).

INDUCTION heating of a metal part is accomplished by placing the part in a magnetic field created by high-frequency, alternating current through an induction coil, thus converting electrical energy into heat and, with enough power supplied, heating the surface regions to the critical temperature in a few seconds. Although this principle is not new, Mr. Vaughn points out that it is only in recent years that the process has been used to any extent as a production method for various heat-treating operations. After mentioning some of the problems involved in using high-frequency current, the author gives examples of typical tractor and engine parts that are being successfully induction hardened in production.

It is the purpose of this paper to discuss in detail unusually precise structural model design, construction, and test procedure. A statement of the laws of similarity to which all structural models must conform if precise results are to be obtained in the simplest manner is given by Mr. Loudenslager. Scale selection, choice of materials, and construction methods are all considered by him. Three model members of designs which can represent a number of prototype properties are described in detail, as well as the use of each of these members, and the determination of bending, torsional, tensile, and compressive stresses by means of simple equipment. In addition, design formulas are set forth for a member which represents the axial, torsional, and bending (in two planes) properties. Finally, three test procedures, all applicable to a variety of simple or complicated indeterminate structures, and the methods used in evaluating the test results are presented by the author.

THEORETICAL principles of cargo pickup are outlined here by Mr. Schultz, who describes the design of pickup units, contact means, transfer equipment, and ground stations for both 200-lb and 60-lb units. He also outlines the basic features desirable in future pickup airplanes, as well as structural design requirements. The author then describes glider pickup, giving consideration to the basic theory behind this type of pickup, the design of pickup units, their installation in the airplane, the cable guide system, and contact means. He outlines the design features of glider pickup airplanes and structural design requirements to be used in the installation of the equipment. In closing the author points out that aircraft pickup has obvious military possibilities and that the peacetime potential is practically unlimited.

THE effect of wartime refinery operations, including the installation of new refining equipment, on the quality and quantity of products that will be available for operating automotive and aircraft equipment is fully discussed here by Mr. Holaday. The author's comments cover aviation fuels, motor gasolines, tractor fuels, diesel fuels, and gas turbine fuels, as well as domestic heating oils and lubricating oils.

THERE is a great deal of room for improvement in future motor trucks, Mr. Cass reports, both along already established lines and in the direction of specialized models for specific purposes. Possible individual improvements actually omit no aspect of the truck from powerplant to driver comfort. Whether or not the gas turbine will have a place in future trucks depends, the author believes, on how it stands up against the future reciprocating engine with regard to the considerations of size, thermal efficiency, maintenance, weight, and initial cost.

WHEN subjected to long storage periods, particularly at high temperatures, gasoline may undergo an increase in gum content. For this reason the Ordnance Department requested CRC to recommend the maximum permissible limits of ASTM gum in aged fuels that could safely be used during emergencies. The tests reported in this paper were undertaken by the Gasoline Additives Group of the CFR Motor Fuels Division.

THE first part of this report on the combustion problems that have been encountered in diesel engines presents the results of experiments conducted on fuels of narrow distillation range and 40 to 90 cetane number. The second part deals with the diesel flame, revealing data on its intensity, temperature, and spectra.

THIS report, a discussion of the design problems in heated surface anti-icing equipment, consolidates and compiles all of the heat transfer data known to be available from past experimentation and considered to be required for current and future designs. Consequently, the author believes that the discussion contained herein will be of assistance in some degree to designers and engineers confronted with problems relating to heated surface anti-icing. The report deals with a rapid means of calculating heated wing requirements, charts of heat transfer coefficients, a discussion of instrumentation techniques, and a method of calculating surface temperatures in dry air.

AN electrical analyzer is described here which was designed in order to solve crankshaft torsional vibration problems.

DESCRIBED here are the detailed characteristics of two series of synthetic lubricants, one essentially insoluble and the other soluble in water at room temperature. These lubricants are synthesized from natural or other hydrocarbon gases as raw materials. Results of laboratory and field tests indicate that the lubricants can be successfully used in internal-combustion engines. In fact, the authors report that one of them has already been used extensively in aircraft engines by the Army Air Forces and the Air Transport Command.

DESIGNING a jet engine, Mr. Mock warns at the beginning of his paper, is anything but a simple matter. In addition to the usual powerplant requirements of efficiency, complete combustion, proper temperature distribution, and minimum volume and weight, he points out that the internal-combustion turbine is subject to certain special requirements for aircraft operation, which he outlines as follows: 1. It should start easily, positively, and consistently, without detriment to engine life; it should restart in the air without complex or difficult manipulation by the pilot. 2. The engine should fire without blow-out or die-out at all speeds, altitudes, and throttle positions that the pilot can use in flying. All air/fuel regulation should be automatic; it should not be necessary for the pilot to nurse the throttles. 3.

THE extensive reconditioning of parts that was practiced during the war will slowly be cut down as new parts again become plentiful. Then, Mr. Patras explains, the deciding factor will be cost. The rule as he practices it is: Recondition used parts wherever satisfactory service can be obtained from the reconditioned part and the cost of reconditioning is equal to or below the cost of a new part plus freight and handling. In addition the author suggested that improvements were particularly required in certain specific items, such as steering gears, oil seals, oil pumps, and oil pressure regulating valves. He explained further that if designers were to utilize to the greatest extent possible units and parts already in volume production, the inventory problems of the modern motor bus operators would be greatly simplified, and the cost of repair parts could be just that much less. The shortage of skilled mechanics is also discussed by Mr.

OF the various methods of establishing the size of vehicle brakes that have been in use the author points out that the ones found most satisfactory have been based on the fundamental fact that the brake is an energy-converting unit. Formulation of rating factors at the present time, he says further, shows promise of incorporating the effect of engine horsepower on the brake factors by introducing a time element. For those advocates of a simple method of rating brakes on the basis of liner area, Mr. Super recommends that this area be established on the basis of the projected length of the liner so that the most efficient use of the liner material is obtained.

EMPLOYERS of truck drivers have an important and sometimes difficult job in training their drivers to conserve the vehicles they use. One approach to this problem of training drivers to their responsibilities is presented here by Mr. Sinclair, who sets forth and elaborates on a series of “don'ts” that drivers should diligently and persistently practice.

DESCRIBED here in detail is the package heater developed for the Boeing Stratoliner as the result of cooperative efforts between TWA and two other companies.

AERATION of aircraft-engine oil has spasmodically caused trouble with pressure regulation for several years. A protracted investigation and test program by Wright Aeronautical Corp., though still unfinished, shows by laboratory, test stand, and flight test, that some facts well known for years have been neglected and aeration of oil therefore invited while deaeration has been definitely restrained. A review of basic facts and known methods indicates that if they were taken into account in design and service operation, we could go a long way in reducing trouble with oil pressure regulation due to entrained air, according to Mr. Weeks. The engine itself, obviously, is the main source of entrained air, but the scavenge pumps are not solely responsible, the author reports. Oil fed to them from gear trains contains 6-20% very finely divided air. Entrained air is, he concludes, inherent to engines with integral reduction drive gears, supercharger drives, and multiple accessory drives.

AFTER reviewing the progress that has been made in the motor-coach industry in the past 20 years, the author projects this progress 20 years into the future. He predicts, for instance, that in this period long-distance buses will be 102 in. wide and 40 ft long, because he feels that this space will be needed by the designer to build into these buses the comfort so essential to the continued growth of the industry. In addition, he makes many specific predictions as to what he thinks the future holds in the way of safety, comfort, eye appeal, and public service for the buses of the next 20 years.

THIS paper presents a brief history of past experience at Boeing with turbosupercharged airplanes. Installation problems are discussed by the author who also offers suggestions for future design. A basic airplane and engine are chosen and several types of supercharging analyzed by Mr. Disch. A method of turbo selection is also briefly presented by him. Assuming that flight at 25,000 ft is desired, a comparison of range and payload is shown, depicting the benefits of employing a cruising type of turbosupercharger for increased fuel economy and range. In conclusion, the author summarizes the overall benefits with this type of installation.