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The adoption of turbine engines for automotive power plants has been hampered by the high cost, high leakage and high wear rate of present designs of ceramic-matrix regenerators. Proposals are made and analyzed here for design directions to achieve substantial improvements in all three areas. These include lower-cost extruded and pressed matrices; and clamping seals coupled with incremental movement of the rotary-regenerator matrix.

The automotive gas turbine has not been adopted for many reasons, among which are that the materials required have been expensive, and the fuel consumption has been unremarkable. A new approach is to use a marked reduction in blade speeds (and therefore in blade and disk stresses) through multistaging, allowing the use of injection-molded compressor components and low-cost ceramic materials (e.g. technology developed for automotive turbochargers) for all hot parts. The pressure ratio will also be lowered and the heat-exchanger effectiveness increased. The resulting engine is larger than existing experimental turbines but still smaller and lighter than an equivalent spark-ignition or compression-ignition engine, with a marked improvement in projected fuel efficiency.

The dominant influence of racing regulations on the history of bicycles, and particularly of recumbent bicycles, is described. A new class of racing for human-powered vehicles, set up in 1974, brought about the present enthusiasm for recumbent bicycles. The development of the AVATAR 2000, originally designed to lessen injury risks in commuting, is described, together with modifications that, as the AVATAR BLUEBELL, led to its holding the world 200-m flying-start speed championship 1982-3. Paper closes with predictions of likely future developments.

Two successive surveys and round-robin interviews were conducted to determine if there might be in the offing for automobiles an alternative engine which would exhibit low emissions meeting the most stringent requirements. Comparison between engines were couched in terms of selected “acceptability factors” which went well beyond emissions, alone. The overall acceptability was evaluated considering emissions, customer requirements for an engine, manufacturers' requirements for an engine, and engine efficiency and fuel versatility. An attempt was made to establish a time scale as to R and D requirements and eventual production. Comparison of all engines was made with equivalent pre-control Otto cycle engines as the standard. Alternative engines were deemed to be any power plant that was not based on spark ignition Otto cycle engines, or diesel engines. The remaining heat engines largely used continuous combustion as the heat source.

Terminal design has emerged as having critical importance in the planning of dual-mode transportation in cities because the very high line-haul capacity of automated guideways can lead to large space requirements at entry and exit points. In this paper the influence of vehicle size, the method of guidance and propulsion, and the network terminal layouts on the space requirements for the overall transportation systems are discussed. Forecasts are made of the manner in which dual-mode transportation will first be installed.