What are the two types of fluid lines commonly found in aircraft?

The correct answer identifies the two primary types of fluid lines used in aircraft systems: rigid metal lines and flexible hoses. Rigid metal lines are often constructed from materials such as aluminum or stainless steel, providing durability and resistance to damage, which is essential in the high-pressure environments often found in aircraft systems. These metal lines are used where straight paths and fixed connections are necessary.

Flexible hoses, on the other hand, are made from materials that allow for movement and flexibility, making them suitable for applications where vibration, thermal expansion, or engine movement would make rigid lines impractical. These hoses are typically reinforced with layers to ensure they can withstand high pressures and are often used in hydraulic systems to connect different components.

This combination of rigid and flexible components allows aircraft systems to be both robust and adaptable, which is crucial for maintaining the integrity and reliability of fluid distribution and hydraulic systems in various operational conditions. Options that included materials like wood, glass, or plastic in the context of aviation fluid lines are not suitable due to their inadequate resistance to the harsh realities of aviation environments, such as pressure, temperature extremes, and mechanical stress.