The amber FAULT light in which pushbutton will illuminate if the Reservoir Level in the Green or Yellow system is low?

The amber FAULT light in which pushbutton will illuminate if the Reservoir Level in the Green or Yellow system is low?

• A. Blue ELEC Pump
• B. PTU
• C. RAT pushbutton
• D. EMER GEN

Answer: (B)

The amber FAULT light on the PTU pushbutton warns about a hydraulic condition related to the Green and Yellow systems. The PTU (Power Transfer Unit) transfers hydraulic power from Green to Yellow to keep Yellow system pressure up when it’s needed. If the Reservoir Level in either Green or Yellow is low, the system flags this and the amber FAULT light on the PTU pushbutton illuminates to alert the crew that PTU action may be required or that there’s a reservoir concern. Other lights on different pushbuttons correspond to their own systems—Blue ELEC Pump relates to the electrical pump, RAT to ram air turbine deployment, and EMER GEN to the emergency generator—so they’re not driven by low hydraulic reservoir levels.

The amber FAULT light on the PTU pushbutton warns about a hydraulic condition related to the Green and Yellow systems. The PTU (Power Transfer Unit) transfers hydraulic power from Green to Yellow to keep Yellow system pressure up when it’s needed. If the Reservoir Level in either Green or Yellow is low, the system flags this and the amber FAULT light on the PTU pushbutton illuminates to alert the crew that PTU action may be required or that there’s a reservoir concern. Other lights on different pushbuttons correspond to their own systems—Blue ELEC Pump relates to the electrical pump, RAT to ram air turbine deployment, and EMER GEN to the emergency generator—so they’re not driven by low hydraulic reservoir levels.