Where does air exhausted from cooling displays exit on the ground?

• A. Through the tailcone exhaust.
• B. The ground valve vents air overboard through the bulkhead.
• C. Into the cockpit ventilation system.
• D. It is recirculated to the cabin.

Answer: (B)

When avionics cooling air is used on the ground, it is vented directly outside the aircraft to avoid heat build-up inside the cabin or cockpit. The path used is a ground valve that routes the exhausted air overboard through the bulkhead to the outside. This keeps the cockpit and cabin comfortable and ensures sensitive equipment isn’t heated by recirculated air.

Other paths would not suit the cooling needs: venting into the cockpit ventilation or recirculating to the cabin would bring heat back inside, and the tailcone exhaust is used for different engine or APU exhaust routes, not for avionics cooling.