What component is primarily responsible for emergency landing gear extension?

The hydraulic backup system is primarily responsible for emergency landing gear extension in aircraft like the Dassault Falcon 7X. In normal operation, landing gear extension and retraction are usually controlled by the aircraft's primary hydraulic system, which provides the necessary pressure to operate the landing gear mechanisms.

In the event of a failure in the primary hydraulic system, the hydraulic backup system serves as a failsafe. It allows the pilots to extend the landing gear manually using a separate source of hydraulic pressure. This is crucial for ensuring that the landing gear can be deployed safely to enable a successful landing, thus enhancing the overall safety of the aircraft.

The other components mentioned, such as the manual override switch, pneumatic system, and electrical actuator, do not serve the same primary purpose for emergency landing gear extensions in the event of a hydraulic failure. The manual override switch may allow for some control, but it is the hydraulic backup system specifically that provides the necessary physical pressure to actuate the gear. The pneumatic system is typically not used for landing gear operation in these aircraft, and while electric actuators can be involved in other systems, the hydraulic backup is vital for emergency situations involving landing gear.