Which type of metal is commonly used for aircraft structural components?

Aluminum alloys are commonly used for aircraft structural components due to their favorable strength-to-weight ratio. This characteristic is crucial in the aviation industry, as reducing weight while maintaining structural integrity contributes to improved fuel efficiency and overall aircraft performance. Additionally, aluminum alloys have excellent corrosion resistance, which is essential for aircraft that operate in varying environmental conditions.

While stainless steel is used in certain applications where higher strength and durability are required, it is heavier than aluminum, making it less suitable for most structural components. Cast iron, on the other hand, is rarely used in aircraft structures because it is heavy and brittle, which doesn't align with the performance requirements of aircraft design. Plastic composites are increasingly being utilized in modern aircraft for their lightweight and corrosion-resistant properties, but they do not replace aluminum alloys in traditional structural applications. Thus, aluminum alloys remain the most prevalent choice for constructing aircraft components.