How are the thrust reversers armed and controlled?

• A. Electrically Armed and Hydraulically Controlled
• B. Mechanically Armed and Electrically Controlled
• C. Electrically Armed and Electrically Controlled
• D. Hydraulically Armed and Mechanically Controlled

Answer: (A)

The system separates readiness from movement. The thrust reversers are moved by hydraulic actuators, so the actual deployment is hydraulically controlled. The arming process, which makes deployment possible under the right conditions, is done electronically—an electrical signal from the cockpit or associated systems enables the reversers to operate when commanded. This combination—electrical arming with hydraulic actuation—matches how modern thrust reverser systems are designed for reliable, high-strength movement while keeping deployment under tight electrical safety controls. The other options would imply either mechanical or electrical actuation for movement, which isn’t how these reversers operate on the CRJ‑550.