The empennage, also known as Tail or tail assembly is a device installed on the tail of an aircraft to enhance flight stability. Most tails include horizontal stablizer and vertical stablizer. A few use V-shaped tails. The tail wing can be used to control the pitch, yaw and tilt of the aircraft to change its flight attitude. The tail wing is an important part of the flight control system.
Horizontal stabilizer: It is the the wing surface for longitudinal balance, stability, and control of an aircraft. The horizontal tail is arranged symmetrically at the rear of the aircraft, basically in a horizontal position. The front half of the wing is usually fixed, called a horizontal stabilizer.
Vertical Stabilizer: It plays a role in maintaining the balance, stability and maneuvering of the aircraft. The principle is similar to that of a flat tail. The vertical tail is only arranged on the upper part of the aircraft axis. This is because during take-off and landing, the head of the aircraft is tilted up and the tail is very close to the ground, so the vertical tail surface cannot be arranged. Like the flat tail, the front half of the vertical tail surface is usually fixed, called the vertical stabilizer; the rear half is hinged on the rear of the stabilizer, and can be steered and deflected, called the rudder.
Aluminum Alloy 2024: It has brought tremendous changes to the structure and performance of the aircraft, and at the same time laid the foundation for the development of 2xxx aluminum. Its main elements are Cu, Mg and Mn. Fe and Si are the main impurities.
2024 aluminum alloy is commonly used in T3 and T4 temper,which has which has high plasticity, fatigue life, fracture toughness and fatigue crack growth resistance, but its corrosion resistance is poor. It is mainly used on fuselages, wings, shear ribs and webs, and other structural parts that require high strength.
7075 aluminum sheet: The 7075 aircraft aluminum are usually in forms of aluminum sheet, bars, profiles and forgings. Due to its high strength, it is widely used in important stress parts of aircraft structures, such as aircraft skins, wing beams, bulkheads, long truss,falling gear and hydraulic system components, etc.
In order to improve toughness and corrosion resistance, Boeing 747 began to use 7075-T651 alloy, while Lockheed L-1011 used 7075-T7651 alloy. Airbus A350XWB horizontal and vertical girder, main frame, main landing gear joints, etc. are also made of 7075 aluminum alloy.
7050 aluminum alloy: Because of its good overall performance, 7050 aluminum alloy has been widely used as parts of aircraft fuselage frames, wing spars, and tail wings. Compared with 7075 alloy, 7050 greatly reduces the impurity content of Fe and Si.
After aging treatment, the alloy has higher strength, better fracture toughness, more satisfactory stress corrosion resistance and good hardenability, which is one of the aluminum alloys having good comprehensive performance. In aerospace materials that require high strength, stress corrosion resistance and fracture properties at the same time, 7050 alloy is the first choice.