Which type of metal is commonly used in aircraft structures for its lightweight properties?

Aluminum is the most commonly used metal in aircraft structures primarily due to its lightweight properties, which are crucial for enhancing fuel efficiency and overall performance. Its low density allows for significant weight savings without compromising strength, making it ideal for aviation applications where every ounce counts. Additionally, aluminum has good corrosion resistance, which is essential in the harsh environments aircraft often operate in, such as varying altitudes and weather conditions. The combination of these characteristics—lightweight, strength, and resistance to the elements—makes aluminum a preferred choice for constructing various aircraft components, including wings, fuselages, and other structural elements.