FAA AMT (Aviation Maintenance Technician) Airframe Practice Exam

A sliding vane pump would not effectively separate air and vapor from the fuel, as it works by using a rotating semicircular rotor to push liquid along its vanes. A diaphragm pump uses rubber diaphragms to move the liquid, which is not conducive for efficiently separating air and vapor from fuel. A piston pump operates by drawing in fuel through a one-way valve and then pushing it through a discharge valve, which would not effectively remove air and vapor from the fuel. A centrifugal type pump, however, uses centrifugal force to separate the air and vapor from the fuel before it enters the line to the carburetor. This is achieved by spinning the fuel at high speeds, causing the denser liquid to move outward, while the lighter air and vapor are forced to the center and expelled through a vent, thus ensuring only clean fuel is delivered to the carburetor. Therefore, C is the correct answer for the type of fuel boost pump that effectively separates air and vapor from the fuel before it enters the line to the carburetor.