What should be done after closing the HPU valves?

After closing the Hydraulic Power Unit (HPU) valves, it is essential to open the FADPU (Fuel and Air Distribution Pressure Unit) on each shaft to ensure proper system function and to alleviate any system pressure. This step is crucial because it prepares the hydraulic and power systems for safe operation and maintenance by allowing the pressure to equalize and making sure that the systems are ready for any further actions that may be required, such as maintenance or inspection.

This procedure contributes to maintaining operational safety and efficiency. Engaging the FADPU helps in managing fuel and air supplies effectively, ensuring that every component receives the necessary support without risking pressure build-up that could lead to malfunctions or hazards.