# Dynamics Test Research of Bounce of Carrier-Based Aircraft Arresting Hook
## 2 Test Method for Collision Rebound of Arresting Hook  
The collision rebound test of the arresting hook is a test of the collision dynamic performance in the laboratory environment. During the test, it is necessary to simulate the actual landing conditions, including landing attitude, landing gear cushioning performance, sinking velocity, horizontal velocity, and deck coating. In order to record the dynamic response of the arresting hook during the test, the collision rebound test of the arresting hook is carried out under the condition of the landing boundary.  
The collision and rebound test system of the arresting hook is refitted from the drop test system of the landing gear. The arresting hook is installed on the side of the basket, the buffer device is fixed on the ground below the basket, and the large disc used to simulate the deck of aircraft carrier is installed at the drop point of the arresting hook. In order to ensure that there is no lateral load when the arresting hook collides with the disc, the tangential velocity direction of the collision point is in the same line with the arresting hook, and the schematic diagram of the test system is shown in Figure 1.  
The construction principle of the test system is as follows:  
1. In order to achieve the landing attitude required by the test, that is, to achieve the required deck angle of the arresting hook, the attitude of the disc is adjusted according to the relative motion principle;  
Figure 1: Schematic diagram of the test of arresting hook bounce.  
2. The sink velocity of the aircraft is achieved by the fixed height of the basket. Before the test, the basket is raised to the predetermined height, so that the vertical velocity of the basket and the buffer when they contact is the same as the sinking velocity of the aircraft;  
3. The landing horizontal velocity of the aircraft is achieved by the relative motion of the arresting hook head and the rotating collision disc. When the arresting hook head contacts the collision disc, the corresponding points on the collision disc move at high velocity, simulating the relative motion between the arresting hook and the aircraft carrier deck;  
4. The buffer effect of the landing gear is simulated by the buffer system installed under the basket.  
During the test, firstly check the state of the test piece to ensure that the balance of the whole basket remains level, and check the filling parameters of the arresting hook damper and the basket buffer device. Lift the basket to the specified height, confirm the height of the basket through the displacement sensor, start the aircraft horizontal velocity simulation device, rotate the large disc along the reverse direction of the aircraft, and confirm the rotation velocity of the disc through the rotation velocity sensor. When the rotation velocity of the disc reaches the predetermined value, the basket is released by the remote-control device which can release and lock repeatedly, and the arresting hook drops down with the basket to impact the disc. There is a platform in front of the impact point. After collision and rebound, the arresting hook jumps onto the platform to avoid repeated bouncing and colliding with the disc. A high-speed camera is used to observe the rebound process and record the test data.