How are the primary flight controls operated on a 737-800?

The primary flight controls on a Boeing 737-800 are operated mechanically through control surfaces that are linked to hydraulic power control units. This means that when pilots move the control yoke, it engages control rods and other mechanical linkages that are connected to the aircraft's hydraulic systems. The hydraulic systems then amplify the pilot's inputs, allowing for the massive control surfaces—such as ailerons, elevators, and rudders—to move effectively, providing the necessary responsiveness and control for flight.

The mechanical linkage ensures that the flight controls remain reliable and can operate even in the event of some electronic system failures, contributing to flight safety. Hydraulic assistance is crucial due to the size and weight of the control surfaces, as manual actuation alone would require significant physical effort, rendering it impractical for pilots, particularly in high-speed flight scenarios.

The other options do not accurately describe the system employed on the 737-800. Direct electrical signals for control actuation are characteristic of fly-by-wire systems, which are not utilized in the 737-800. Wireless communication technologies do not play a role in primary flight control operations for commercial aircraft of this type and would pose critical safety concerns. Similarly, the use of manual levers alone would be insufficient for effective control,