What does the message BLEED CLOSED indicate about the APU status?

What does the message BLEED CLOSED indicate about the APU status?

• A. APU is Off
• B. APU is On
• C. Bleed Valve Open
• D. Bleed Valve Closed

Answer: (B)

Bleed air status shows which source is feeding air to the packs and to start the engines, and whether that path is open or closed. When you see the message that the bleed is closed, it means the bleed valve path is not currently allowing bleed air through. On the CRJ-550, that closed state can occur even with the APU running, because the bleed path is isolated while the APU is powered and ready to provide air if needed. So this indication points to the APU being on and available, rather than completely off. If the APU were completely off, you wouldn’t be in a state where the bleed path is just closed but the APU is ready; and if the bleed valve were actually open, you’d see a different indication.

Bleed air status shows which source is feeding air to the packs and to start the engines, and whether that path is open or closed. When you see the message that the bleed is closed, it means the bleed valve path is not currently allowing bleed air through. On the CRJ-550, that closed state can occur even with the APU running, because the bleed path is isolated while the APU is powered and ready to provide air if needed. So this indication points to the APU being on and available, rather than completely off.

If the APU were completely off, you wouldn’t be in a state where the bleed path is just closed but the APU is ready; and if the bleed valve were actually open, you’d see a different indication.