In engine failure scenarios, which module is prohibited from use?

In engine failure scenarios, which module is prohibited from use?

• A. FMS Speed Module
• B. GPS
• C. Autopilot
• D. Flight Director

Answer: (A)

In engine-out situations, you must rely on manual speed control aligned with the engine-failure procedures. The FMS Speed Module is prohibited because it is designed to follow the flight management system’s computed speed Schedule based on normal, symmetric-thrust flight. With one engine inoperative, performance changes dramatically, and the automated speed guidance from the FMS can push the airplane to speeds that don’t provide the necessary climb performance or stall margins. This automation can conflict with the pilot’s action to maintain safe airspeed and handling characteristics for the engine-out condition. The other systems (GPS, autopilot, flight director) can be used as appropriate per procedure, but the FMS Speed Module specifically should not be relied upon during engine failure.

In engine-out situations, you must rely on manual speed control aligned with the engine-failure procedures. The FMS Speed Module is prohibited because it is designed to follow the flight management system’s computed speed Schedule based on normal, symmetric-thrust flight. With one engine inoperative, performance changes dramatically, and the automated speed guidance from the FMS can push the airplane to speeds that don’t provide the necessary climb performance or stall margins. This automation can conflict with the pilot’s action to maintain safe airspeed and handling characteristics for the engine-out condition. The other systems (GPS, autopilot, flight director) can be used as appropriate per procedure, but the FMS Speed Module specifically should not be relied upon during engine failure.