General Authority of Civil Aviation (GACA) Aeronautical Information Publication (AIP) Practice Exam

What feature allows the alternate hydraulic brakes to function when required?

1. Reserved hydraulic fluid from other systems

2. A dedicated electric pump

3. A standpipe in the center hydraulic reservoir

4. Manual activation by the pilot

The correct answer is: A standpipe in the center hydraulic reservoir

The functionality of alternate hydraulic brakes is primarily supported by a standpipe located in the center hydraulic reservoir. This standpipe ensures that in the event of a primary hydraulic system failure, there is still access to hydraulic fluid that can maintain the operation of the brakes. When the primary system is compromised, the fluid drawn from the standpipe provides enough pressure to allow the alternate brakes to operate effectively, thereby maintaining control and safety during operations. While other options might suggest alternative methods for activating or providing hydraulic pressure to the brakes, they do not specifically address the crucial role of the standpipe in ensuring a reliable supply of fluid when the primary system is unavailable. This design is essential for redundancy in aircraft systems, enhancing safety by ensuring that alternate braking capabilities are accessible even under failure conditions.