Defence Turkey: Can we start our interview with a brief overview of the importance of the Wind Tunnel in the design and development process of an aircraft? Can you provide some information about the tests performed in the Wind Tunnel and the average duration of these tests?

Turkish Aerospace: Wind tunnel tests, along with Computational Fluid Dynamics (CFD) and flight tests, have an essential place in the aircraft design process. According to NASA, these three disciplines form a pillar for the data source that needs to be created to evaluate the aircraft. Computational fluid dynamics uses computer-based numerical algorithms to simulate computer models of aircraft in different flight conditions. However, in some cases, certain simulations such as flow separation and high angle of attack may not bring reliable results depending on the speed and flight conditions. It also requires substantial computing resources to get the results. In a wind tunnel, on the other hand, a scaled model of the real aircraft is held stationary inside the tunnel, and the air is moved instead. The limiting factors of the wind tunnel are the air velocity and the model dimensions related to the test section. Depending on these two factors, the importance of the Reynolds number increases. In general, as the weather conditions change, it can be difficult to repeat the tests under the same conditions. Different types of tests are possible in the wind tunnel, such as database tests, air intake tests, and alternative configurations (such as wing, nose, tail). Depending on the purpose, test activities are completed between 1 week to 3 months.