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

What happens to the landing gear during alternate extension using the electric hydraulic pump?

1. It locks in an intermediate position

2. It free-falls to the down and locked position

3. It remains partially deployed

4. It activates the emergency brakes

The correct answer is: It free-falls to the down and locked position

The landing gear’s alternate extension mechanism is designed to ensure that the landing gear can be deployed even in the event of a failure of the normal extension system. When using the electric hydraulic pump for alternate extension, the landing gear is allowed to free-fall into the down and locked position under the influence of gravity. This process is crucial for maintaining safety during an emergency landing scenario. As the landing gear descends, it is typically designed to lock automatically upon reaching its fully extended position, providing assurance that the aircraft will be ready for landing. This method bypasses the complications that can arise from mechanical or hydraulic failures, ensuring that the landing gear can be deployed in a timely and effective manner. The other options do not accurately reflect the operation of the landing gear in this scenario. The gear does not lock in an intermediate position nor does it remain partially deployed, which are not typical behaviors of the system during alternate extension. There is also no activation of emergency brakes involved in the process of extending the landing gear using the electric hydraulic pump. Thus, the mechanism is specifically designed for the landing gear to free-fall to ensure a reliable and safe deployment.