Synthetic-based hydraulic fluid is typically found in which quantity throughout the aircraft?

• A. Moderate quantities
• B. High quantities (approaching 200 gallons)
• C. Large quantities
• D. Small quantities

Answer: (B)

The total amount of hydraulic fluid carried on an aircraft is tied to how many hydraulic circuits and reservoirs are onboard. Synthetic-based fluids are used across multiple systems, so when you add up the fluid in all the reservoirs, pumps, lines, and actuators, the volume becomes substantial. On larger aircraft, there are several independent hydraulic systems that must be supplied with fluid, leading to a sum that is best described as high—often approaching 200 gallons. This reflects the extensive network needed to power flight control surfaces, landing gear, brakes, and other systems. Smaller aircraft have less total fluid, but for most larger aircraft the overall quantity is indeed high and can be near that 200-gallon mark.