Which statement regarding VMCA assumptions is incorrect?

The scenario presented involves VMCA, which is the minimum control speed air, a critical safety parameter for multi-engine aircraft. This speed is crucial for ensuring that the aircraft can be controlled with one engine inoperative.

Feathering an inoperative engine—where the propeller blades are turned to a position that minimizes drag—is a typical strategy used to enhance performance when one engine fails. However, for the assumptions related to VMCA, it is generally assumed that the inoperative engine is not feathered. VMCA is determined based on an engine operating in a fixed position that generates drag; therefore, if the engine is feathered, the assessment of the aircraft's ability to maintain control in this situation would be incorrect.

The other assumptions related to VMCA are accurate: the aircraft being in a clean configuration means that no additional drag is added by extended landing gear or flaps, the center of gravity being at limit ensures that the aircraft is in the most challenging position to control, and operating only one engine pertains directly to the definition of VMCA. All these factors combine to provide a clear and defined threshold for aircraft performance following an engine failure, which aligns with standard flight safety protocols.