Which component is crucial for maneuvering and directional control of the EJet?

The ailerons are crucial for maneuvering and directional control of the EJet. They are movable surfaces located on the wings that control the aircraft's roll. When the pilot wants to turn the aircraft, moving the control yoke or stick creates a differential movement between the ailerons: one aileron goes up while the other goes down. This difference in lift between the two wings causes the aircraft to roll in the direction of the raised aileron, allowing for effective turning and control during flight.

While the other components listed play important roles in the overall operation of the aircraft, they do not specifically provide the same level of control for maneuvering and directional changes. The throttle controls engine power and thus affects altitude and speed but does not influence roll. The landing gear is important for takeoff, landing, and ground maneuvering but does not assist in the aircraft's in-flight directional control. Flaps are used to increase lift and drag during takeoff and landing, altering the flight characteristics, but they do not provide the primary ability to maneuver or turn the aircraft in flight like the ailerons do.