Which aircraft requires clean power?

The 787 requires clean power due to its advanced technology and systems that are designed for efficiency and eco-friendliness. The clean power requirements pertain to providing clean, stable, and uninterrupted electrical power to support the aircraft's sophisticated avionics, flight control systems, and other electrical loads. The 787 utilizes a unique electrical system that operates on a more electric architecture, meaning it relies heavily on electric systems instead of hydraulic systems for many functions. This reliance on electrical power makes it crucial to ensure that the power supplied is clean and free from fluctuations or disruptions that could affect the performance or safety of the aircraft's systems.

In contrast, while the 747, A320, and 777 are also equipped with electrical systems, they do not have the same stringent clean power requirements as the 787. Their systems have different designs that may accommodate variations in power, relying on a mix of hydraulic and electric systems. Therefore, the necessity for clean power is a defining characteristic of the 787, making it the correct choice in this scenario.