"Expressions were derived for cycle thermal efficiency, work ratio, related useful work, and relative temperatures, and pressures at significant stations, all for a representative direct closed gas-turbine cycle. A parametric study of this cycle was performed for He and N/sub-2/ as coolants. Results of this parametric study are given in tables and charts. Four different cycles, corresponding to the maximum cycle temperatures equal to 1300, 1500, 1700, and 2000 deg F, were established for each of the gases. On the basis of these cycles, consistent form sheets were prepared for inquiries to manufacturers regarding their capabilities and availability of components."