GSM Chief Practice Test 2026 – Complete Exam Prep

The correct answer is that four 4-way, 3-position solenoid-operated valves are used to control the cushion vanes on the LCAC (Landing Craft Air Cushion). Understanding the function of the cushion vanes is crucial as they help to manage the air flow and lift under the craft, facilitating hover and lateral movement. Each solenoid-operated valve is responsible for directing hydraulic fluid to operate the vanes effectively in order to achieve the desired control and stability when the craft is in operation.

The design of using multiple solenoid-operated valves ensures that the system is capable of providing precise control over each cushion vane's position, thus allowing for fine-tuning of lift and maneuverability. Utilizing four valves enables comprehensive coverage of the operational needs for the LCAC, ensuring that the craft can efficiently manage its buoyancy and stability across various conditions.

The chosen number reflects the engineering requirements to achieve the right balance and responsiveness in an air-cushion craft, highlighting the importance of redundancy and control in such systems.