When extending the gear using the emergency system, which statement is correct?

• A. The emergency system gear extension actuators are pressurized
• B. The primary hydraulic lines are pressurized to 3000 +/- 120 psi
• C. The accumulator discharges to the system
• D. The gear doors close

Answer: (A)

The key idea is that emergency gear extension uses pre-pressurized actuators to push the gear into the down and locked position even when the main hydraulic system is not available. When the emergency system is activated, those gear extension actuators already have stored hydraulic pressure, so they can extend the gear firsthand without relying on the primary system. That’s why the statement about the emergency system gear extension actuators being pressurized is the best description of how this system works.

The other statements don’t fit this mechanism: the primary hydraulic lines aren’t the source of emergency extension pressure, and specific numbers like 3000 +/- 120 psi aren’t the defining feature of the emergency function. The accumulator’s role is to provide stored energy, but saying it merely “discharges to the system” doesn’t directly describe how the gear is actually extended. And gear doors don’t close to extend the gear; during extension the doors would be opened or moved as the gear comes down.