Phillips 66® Aviation Antirust Oil is a rust preventive oil specially formulated to help protect aircraft piston engines against rust and corrosion during extended periods of inactivity. Airframe manufacturers have used it for many years as “Fly Away Oil” for new or rebuilt aircraft engines that are expected to sit idle for extended periods of time. Aviation Antirust Oil may be used as “break-in oil” where an all-mineral oil is desired, and is particularly suited for situations where the engine to be broken in may not be immediately put into regular service.