AEROSPACE

Auto Makers Ready New Air-Conditioning System: Chrysler Corp. and Ford Motor Co. said all of their vehicles will have environmentally friendlier air-conditioning systems by January, beating a federal deadline by two years. General Motors Corp. said it will be using the new air-conditioning refrigerant, R-134a, in all vehicles by late next year, when 1995 models arrive. The moves are to eliminate the ozone-depleting R-12 refrigerant, also sold as Freon, which is suspected of contributing to the destruction of the Earth’s ozone layer. While friendlier to the atmosphere, the R-134a systems are less efficient than their predecessors and need more space in the engine and more power to cool as effectively as R-12.