The secondary power systems on the L-1011, that is, the hydraulic, electrical power, pneumatic systems and their components, were all designed with the total aircraft system operation integrated into each subsystem as a firm design requirement. In some cases where supplier components had a major effect on systems design, the supplier was given responsibility to integrate some or all of a secondary power system.
A detailed analysis of aircraft operation, including the required redundancy, was developed as a portion of each system design. Then the interaction of the systems was considered in determining the final design configuration.
This paper deals with the design philosophy used in each of these power systems, and their description and operation. It draws conclusions concerning the improvements in system or design approach which may be proposed for future designs.