Chapter 14 Aircraft Fuel System Basic Fuel System Requirements All powered aircraft require fuel on board to operate the  engine(s). A fuel system consisting of storage tanks, pumps,  filters, valves, fuel lines, metering devices, and monitoring  devices is designed and certified under strict Title 14 of the  Code of Federal Regulations (14 CFR) guidelines. Each  system must provide an uninterrupted flow of contaminant- free fuel regardless of the aircraft’s attitude. Since fuel  load can be a significant portion of the aircraft’s weight,  a sufficiently strong airframe must be designed. Varying  fuel loads and shifts in weight during maneuvers must not  negatively affect control of the aircraft in flight.