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The following work was done in support of a continuing program to better characterize the behavior of the human chest during blunt sternal impact. Previous work on this problem has focused on determining the force-time, deflection-time, and force-deflection response of embalmed and fresh cadavers to impact by a 15 cm (6 in) diameter striker of variable mass traveling at velocities of 22.5-51 km/h (14-32 mph) and striking the sternum at the level of the fourth intercostal space. Additional questions persist concerning whether the anterior and posterior regions of the chest behave as highly damped masses or oscillate after impact, the relationship between force delivered to the surface of the body and the acceleration of the underlying regions, and the influence of air compressed in the lung on thoracic mechanics.

The incentive for use of an interstage diffuser in a free-shaft gas turbine engine is briefly examined and some pertinent published background data reviewed. Tests of two annular diffusers behind an upstream turbine show the deleterious effects of turbine exit flow nonuniformity on diffuser behavior. The flow acceleration provided by the area contraction of a power turbine nozzle located at the diffuser exit substantially improves the nature of the flow previously found to exist at the diffuser exit in the absence of the nozzle.

A professional high diver, instrumented with accelerometers, performed sixteen dives from heights between 27-57 ft. For each dive, he executed a 3/4 turn and landed supine on a 3-ft deep mattress which consisted of pieces of low-density urethane foam encased in a nylon cover. Using FM telemetry, sagittal plane decelerations were recorded for a point either on the sternum or the forehead. Impact velocities and corresponding stopping distances for the thorax and the head were calculated from high-speed movies of the dives. For a 57-ft dive, the impact velocity of the thorax was 41 mph with a corresponding stopping distance of 34.6 in. The peak resultant deceleration of the thorax was 49.2 g with a pulse duration of 100 ms. The maximum rate of change of the deceleration of the thorax was 5900 g/s. No discomfort was experienced as a result of this impact. The maximum forehead deceleration occurred during a 47.0-ft drop and exceeded 56 g with a Gadd Severity Index greater than 465.

Two steam-powered passenger ears have been designed, built, and tested. The SE-101 is an intermediate sport coupe incorporating the comfort and convenience features of a modern passenger car and vehicle performance comparable to a low-powered automobile. The SE-124 is a very low-power intermediate sedan with manual start and semiautomatic control. The characteristics of these cars were evaluated relative to the operational requirements of current transportation needs, with particular emphasis on exhaust emissions. Start-up time, exhaust emissions, fuel economy, acceleration, and water consumption data are presented. Although any one of these characteristics may be improved at the expense of others, it does not appear that any compromise can satisfy all of the areas required by today's motorist.

A novel method for the intermittent supercharging of an internal combustion engine in a vehicle is described. During full throttle operation, high pressure motivating air entrains ambient air and compresses it to an intermediate pressure in the diffuser of an air ejector. Flowing through the carburetor and into the engine, the supplemental air augments engine power, reducing vehicle acceleration time by as much as one-third. By allowing engine size to be reduced, better economy without loss of performance is possible. Typical vehicle installations are described and problem areas discussed.

The conflicts in the design of turbines for an automotive gas turbine engine are examined. Considerations of stress, efficiency, engine and vehicle acceleration requirements, and compatibility of the flow path are shown to impose a number of opposing requirements. The philosophies used to compromise the conflicts in two successive engine designs are presented. Following a discussion of turbine test facilities, test results are presented for a typical turbine.