Which PMU is designated for hydraulic systems?

The PMU-71 is designated for hydraulic systems, which makes it the correct answer. In the context of aircraft maintenance and operations, specifically concerning hydraulic systems, each PMU (Power Management Unit) has specific responsibilities. The PMU-71 is dedicated to managing and monitoring the hydraulic components and systems, ensuring that pressures and fluid levels are maintained within operational parameters. This unit is critical for the functionality of various control surfaces and landing gear, which rely heavily on hydraulic pressure to operate effectively.

By contrast, the other PMUs serve different functions, such as managing electrical systems, fuel systems, or other specific operational needs of the aircraft, which do not pertain directly to the hydraulic systems. Understanding the unique roles of each PMU is essential for proper maintenance and operation protocols in ensuring aircraft safety and efficiency.