The device responsible for activating the emergency hydraulic package's selector valve is the which component?

• A. Landing gear emergency extension handle
• B. Emergency accumulator
• C. Helium pre-charge
• D. 3500 psi pressure release valve

Answer: (A)

The device that activates the emergency hydraulic package’s selector valve is the landing gear emergency extension handle. When you pull this handle, a mechanical linkage shifts the emergency selector valve, routing the stored hydraulic fluid from the emergency package to the gear extension or other actuators needed in an emergency. This manual activation is what makes the emergency hydraulic system usable when the normal pumps or circuits aren’t available.

The emergency accumulator simply provides stored hydraulic pressure, not the actuation signal. Helium pre-charge and the 3500 psi pressure release valve are involved in pre-charging or safeguarding pressure, not in triggering the selector valve.