What type of leaks are considered a flight hazard?

Leaks in enclosed areas near heat sources pose a significant flight hazard primarily due to the potential for fire or explosion. In aircraft systems, enclosed areas often contain electrical wiring and components that can generate heat. If a flammable substance such as fuel or hydraulic fluid leaks in these areas, it can easily ignite when exposed to sparks or high temperatures, leading to catastrophic consequences.

The risk increases in enclosed spaces where ventilation might be limited, making it harder for any flammable vapors to dissipate. This type of leak, therefore, requires immediate attention and remediation to ensure safety during aircraft operations, as the consequences of a fire or explosion could be dire not just for the aircraft itself, but for the crew and passengers on board.

In contrast, while leaks in fuel tanks and other types of leaks can present hazards, they may not pose as immediate a risk as those occurring in proximity to heat sources in confined spaces.