Abstract: The present example provides aircraft integrated aircraft utility management and power distribution systems. Included are three exemplary implementations of aircraft power management systems (a DC power distribution system, a utility management system, and a combined system) that may utilize the like architecture, technologies, and components advantageously. A DC power distribution system can include two parts: primary DC power distribution and secondary DC power distribution systems. The utility management system integrates aircraft sub functions and utilities into one fault tolerant system. The systems described makes use of secondary power distribution units of a modularized design, including standard I/O modules, power modules, and aircraft computing modules.