Which type of wood is most commonly used in aircraft structures?

Sitka spruce is the most commonly used wood in aircraft structures due to its superior strength-to-weight ratio, excellent rigidity, and favorable workability. This type of wood has been a standard choice in aviation, particularly in the construction of wings and other critical structural components. Its combination of lightness and strength makes it ideal for maintaining structural integrity while minimizing overall weight, which is crucial for aircraft performance.

The specific properties of Sitka spruce, including its ability to withstand the stresses and environmental conditions encountered in flight, have led to its widespread acceptance in both commercial and military aviation sectors. Additionally, its availability and the historical tradition of using Sitka spruce in aircraft design contribute to its preference among manufacturers.

Other woods like pine, birch, and oak may have certain advantageous properties, but they do not match the combination of characteristics that make Sitka spruce the go-to choice for aircraft structures. Pine, while lightweight, may not have the same structural strength. Birch tends to be heavier and less ideal for the specific aerodynamic demands of aviation. Oak, though very durable, is quite heavy and less suitable for applications where weight reduction is critical. Thus, Sitka spruce remains the preferred material for ensuring the performance and safety of aircraft.