Environmental Control System Considerations for Supersonic Cruising Aircraft

Weight and the thermal environment will be major considerations in designing supersonically cruising aircraft. Because of aerodynamic heating, larger capacity environmental control systems will be required. Techniques to help minimize their weight and drag are illustrated. Factors for selecting from among various environmental systems are outlined. Low air pressure and heat sink problems are causing the air-cycle to grow in weight and complexity, but air-cycle probably will be the most acceptable for the first supersonic transports. Fuel will be used extensively as a heat sink, but heat sink conservation practices will be required. Some XB-70 experience, emphasizing weight control, is included.