To prevent aeration of the fuel lines in a jet transport aircraft, the fuel system includes

• A. Boost Pumps
• B. Fuel Heaters
• C. Vent Pumps
• D. Auxiliary Tanks

Answer: (A)

Keeping fuel lines primed and pressurized to prevent air from being drawn into the system is essential for reliable engine fuel flow. Boost pumps sit in the fuel tanks and provide a positive-pressure supply to the engine-driven pumps and the common fuel manifold. This keeps the lines filled with liquid fuel during starts, crossfeed, or when tank suction could otherwise pull air in—so you don’t get aeration, which can cause interruptions or flameout.

Fuel heaters focus on warming fuel to prevent icing or waxing, not on keeping the fuel lines free of air.

Vent pumps manage tank venting and vapors, not the pressure feeding the engines.

Auxiliary tanks add capacity, but by themselves they don’t address keeping the primary lines free of air during operation.