What is the Ram Air Turbine (RAT) and when would it deploy?

• A. The RAT provides emergency electrical power (and sometimes hydraulic power) in a loss of normal power; deploys automatically if required.
• B. The RAT is a backup air conditioning unit; deploys manually on request.
• C. The RAT powers the flight deck lighting and is deployed during night operations.
• D. The RAT provides extra thrust during takeoff; deploys automatically when thrust is insufficient.

Answer: (B)

RAT is a small turbine that extends into the airstream in an emergency to supply power when normal sources fail. It provides emergency electrical power and hydraulic power to essential systems, keeping critical flight controls and avionics powered until normal power is restored. It’s designed to deploy automatically when required, so there’s no crew action needed in flight. It’s not an air conditioning unit, it doesn’t power cabin lighting or extra thrust, and its main purpose is emergency power, not regular equipment operation.