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The paper is a presentation of a practical solution for the coordination of military and commercial transport with rail and water transport. The necessity for combining and coordinating transportation facilities with the idea of organizing a homogeneous transportation network of waterways, railways and highways, proved to be the essence of success in military operations during the World War. The utter inadequacy of pre-war and war-time transport facilities, when organized in the separate fields of railroad, maritime shipping and port operations, and the decentralized elements of highway transport, caused the United States Army to make a comprehensive study and plan of the world's war-time transportation with particular attention to the organization of motor transport as the necessary factor in coordinating all transportation facilities. The salient features and general principles of this study and the resultant plan are stated.

The views expressed in this discussion are those of the speaker and do not represent necessarily the views of the War Department.

Military and commercial turbofan STOL transport work at the Douglas Aircraft Company during the past four years has led to the consideration of commonality between the USAF Medium STOL Transport and a short-range, medium-sized commercial STOL transport. General requirements for the two airplanes appear to be similar and include a cruise speed of Mach 0.75-0.80 for a 500-nautical mile range after takeoff from a 2000-foot airstrip. Both require a wide body; and the payload, furnishings, and equipment yield comparable STOL takeoff weights. Both can be designed with a high wing, a moderate wing loading, and the same STOL lifting concept. A common engine size appears feasible, and basic engine characteristics such as bypass ratio need not be different. Results of a preliminary commonality study are presented in which several cases with varying degrees of commonality are evaluated in terms of costs.

This paper surveys publications on automotive powertrain control, relating to modern GTDI (Gasoline Turbocharged Direct Injection) engines. The requirements for gasoline engines are optimising the airpath but future legislation suggests not only a finely controlled airpath but also some level of electrification. Fundamentals of controls modelling are revisited and advancements are highlighted. In particular, a modern GTDI airpath is presented based on basic building blocks (volumes, turbocharger, throttle, valves and variable cam timing or VCT) with an example of a system interaction, based on boost pressure and lambda control. Further, an advanced airpath could be considered with applications to downsizing and fuel economy. A further electrification step is reviewed which involves interactions with the airpath and requires a robust energy management strategy. Examples are taken of energy recovery and e-machine placement.

Market trends for increased engine power and more electrical energy on the powergrid (3kW+), along with customer demands for fuel consumption improvements and emissions reduction, are driving requirements for component electrification, including turbochargers. GTDI engines waste significant exhaust enthalpy; even at moderate loads the WG (Wastegate) starts to open to regulate the turbine power. This action is required to reduce EBP (Exhaust Back Pressure). Another factor is catalyst protection, where the emissions device is placed downstream turbine. Lambda enrichment or over-fueling is used to perform this. However, the turbine has a temperature drop across it when used for energy recovery. Since catalyst performance is critical for emissions, the only reasonable location for an additional device is downstream of it. This is a challenge for any additional energy recovery, but a smaller turbine is a design requirement, optimized to operate at lower pressure ratios.

Claims and counter-claims as to the deceleration possible under certain conditions, especially when applied to the legal questions arising at the time of an accident, induced the author to make an investigation of the subject. An attempt has been made to include all the variables that are of significance or of sufficient magnitude to affect appreciably the performance of a car under a given set of conditions of the vehicle or of the environment. Inasmuch as the calculations are simplified by doing so and because the difference between the amounts of deceleration and of power involved are small, the assumption is made that the maximum deceleration occurs when the wheels are locked, rather than when they are still rotating. The stopping-distances, theoretically obtained, apply to level-road conditions only.

DURING the war the trend of tractor engine design toward increased efficiency resulted in many improvements and discoveries in accessories, not the least of which is the carbureter air-cleaner. The value of air-cleaners is now fully recognized and they are used as standard equipment on the majority of tractors. Air-cleaners are classified into groups as follows: (a) cleaners having cloths or screens, or both, to catch dust; (b) inertia cleaners; (c) those employing water or some other liquid to trap dirt and (d) centrifugal or gravity cleaners. The first class is practically obsolete; illustrations of two of this type are shown. Inertia cleaners are not widely used, but present possibilities. Liquid cleaners of various designs are in considerable use. The author believes that the slight advantage in efficiency of this type over the better class of dry-type cleaners is not sufficient to compensate for their greater size and difficulty of operation.