Can a fuel system develop a leak without visible evidence, and how?

A fuel system can indeed develop a leak without visible evidence, particularly if it involves internal components like valves or fittings that may be hidden from view. Internal leaks can occur due to wear, corrosion, or malfunction of these components, and the fuel may escape into spaces that are not easily observable. For example, a valve that is worn or improperly seated might allow fuel to seep out, but this leakage might not manifest as a visible stain on the exterior of the aircraft, since it is contained within the system.

Understanding the nature of fuel leaks is critical for maintenance and safety. External corrosion is a risk that can create leaks but usually presents visible signs of wear or damage. It’s also worth noting that while fuel stains are common indicators of leaks, they are not always present, especially in scenarios where the leak is internal or small enough to evade detection until it becomes a more serious issue. Hence, the focus on internal components is crucial in understanding how a fuel system can lose integrity without clear visual indicators.