What is Air Minimum Control Speed (VMCA)?

Air Minimum Control Speed (VMCA) is the minimum speed at which an aircraft can maintain controlled flight with one engine inoperative. This critical speed is particularly important for multi-engine aircraft because, in the event of an engine failure, the aircraft must remain controllable, ensuring that the pilot can offset the yaw and roll tendencies caused by the loss of thrust. At speeds below VMCA, the control effectiveness is insufficient to counteract the asymmetrical thrust produced by the functioning engines, potentially leading to a loss of control.

The significance of VMCA becomes evident during takeoff and initial climb phases when engine failure is a possibility. Knowing this speed helps pilots ensure that they remain above it in situations where engine failure might occur, allowing for safe maneuverability and minimizing the risk of stalling. Therefore, the correct understanding of VMCA is crucial for safe flight operations in multi-engine aircraft.