*2.6. Drop Test Laboratory Setup for Reaching the Opening Shock Load*

In order to reach the inputs in the harness load test, it is necessary to obtain data from the actual drop, which reflects parachute aerodynamic characteristics during the opening phase. For this purpose, a special drop test laboratory has been developed. The scheme, with a description of the basic components, is highlighted in Figure 8. The test laboratory consists of electronics that record the most important information regarding the entire drop in real time. The high recording frequency allows the system to be activated with

high accuracy and is also very important for the next postprocessing of the data. Not only speed-related information is recorded, but also the duration of the freefall, forces in separate connections between parachute and laboratory, position in the coordinate system, and G-force. Data from the indicated speed and free fall time are used to activate the system at the required speed. Exceeding the design speed should mean the destruction of the parachute, and in most cases, damage to the laboratory caused by high-speed impact with the ground.

**Figure 8.** A scheme of a fully equipped laboratory mounted on the AN-2 before takeoff.

Information related to G-Force and load in separate connections is the value that needed to be identified for further analysis. Even though the laboratory records the complete progress of the quantities over the whole drop test sequence, for the present research, only one point is important, which is the maximum peak related to the opening shock load. The amount of asymmetry read from the measuring carabiners on the attachment points can be considered as additional information and input to the proposed tests 2 and 3.

It should be highlighted that the activation of the parachute must be executed in the same manner as if it were activated by a skydiver while wearing the serial harness. That means that the folding of the parachute into the storage area needs to be executed in the same way and deploying the drogue chute equipped with the serial extracting spring is also required. There should be free space in the area of deployment that would cause the elements to be trapped during the pulling sequence. This ensures that there will be no unwanted delay in the deceleration of the ballast. It is an important parameter for drop tests that use gravitation to accelerate the laboratory to the final speed. Any delay in activation thereafter means exceeding the design speed, which is unacceptable.
