If an aircraft is going to exceed 80% power, where must it go?

The correct choice indicates that an aircraft must go to the high power area when exceeding 80% of its power. This designation is critical for safety reasons. The high power area is specifically established to accommodate aircraft operations that require higher levels of thrust, which could entail potentially more significant noise and energy output. By using a designated area, it ensures that these operations are conducted away from personnel, equipment, and other sensitive areas, minimizing the risks associated with high power engine use.

In contrast, the other options suggest places that do not cater specifically to high power operations. The ground control area is likely intended for general maneuvers and operations within a controlled environment but is not suitable for extensive power outputs. The emergency recovery area is generally intended for unexpected situations and not for routine high power operations. The maintenance hangar is focused on repair and upkeep rather than operational activity, making it unsafe for an aircraft to be operated at high power levels. Thus, the high power area is the appropriate location for an aircraft exceeding 80% power for operational safety.