--- title: Airfoil (English) slug: airfoil-english url: /detay/airfoil-english type: article language: English entity: primary: Airfoil (English) type: article disambiguation: Airfoil: Understand lift, drag, and flight dynamics. Learn about airfoil design, its key components, and how it enables flight. categories: - name: Machinery, Robotics And Mechatronics slug: makine-robotik-ve-mekatronik url: /kategori/makine-robotik-ve-mekatronik - name: Aviation And Space slug: havacilik-ve-uzay url: /kategori/havacilik-ve-uzay tags: - Angle of Attack - Bernoulli's Principle - Lift - Aerodynamics - Airfoil author: Fatih Türk created_at: 2025-01-28T20:44:54.544607+03:00 updated_at: 2025-04-17T12:33:11.889603+03:00 --- # Airfoil (English) ## Article Content [An](/en/detay/an-2/llms.txt) [airfoil](/en/detay/airfoil/llms.txt) is the two-dimensional cross-section of objects that move through a fluid, such as wings, propellers, rudders, or sails. These sections are designed to provide the optimal lift-to-drag ratio for vehicles moving through fluids like air or water. Typically curved or flat, and often resembling a teardrop shape, airfoils function by creating a pressure difference on their two opposing surfaces based on [Bernoulli’s principle](/en/detay/bernoulli-equation-6c9fc/llms.txt). This pressure difference generates aerodynamic forces, enabling airplanes to stay aloft. ![Image](https://cdn.kureansiklopedi.com/media/uploads/2025/01/27/vhoaLZzqc1FrSG9ZPFaqdNx7xCxOJqVN.webp) *Airplane Wing* The geometry of an airfoil determines how air flows around it, which is one of the most critical factors in enabling flight. An airfoil [has](/en/detay/has-3/llms.txt) two primary surfaces: - **Upper Surface**: Usually convex, it allows air to flow faster, creating a low-pressure area and generating lift based on Bernoulli's principle. - **Lower Surface**: Often flatter or concave, it causes slower airflow and generally higher pressure. ##### **Key Airfoil Concepts** 1. **Leading Edge**: The front edge where the air first contacts the airfoil. 2. **Trailing Edge**: The rear edge where the air leaves the airfoil. 3. **Chord Line**: A straight line connecting the leading and trailing edges. 4. **Camber**: The curvature of the airfoil, influencing lift generation. 5. **Thickness**: The measurement of the airfoil’s thickest part, which impacts aerodynamic performance. ![Image](https://cdn.kureansiklopedi.com/media/uploads/2025/01/27/vsG1hMM0IEgBRpjPBiFmNvGnmfm2EnMG.webp) *Airfoil concepts* Airfoils are optimized based on flight speed, the purpose of the aircraft, and its mission profile. For instance: - High-speed aircraft use thinner airfoils to minimize drag. - Aircraft that perform at lower speeds or require greater maneuverability use thicker, more cambered airfoils. In a typical airfoil, the curved upper surface creates a longer path for airflow than the lower surface. This causes air on the upper surface to move faster, reducing pressure compared to the lower surface. This pressure difference generates [aerodynamic lift](/en/detay/aerodynamics-dictionary/llms.txt). ![Image](https://cdn.kureansiklopedi.com/media/uploads/2025/01/27/GtNGmFQDwSbGAL2N1a6taaxWq2kPGgyY.webp) *Lift Force Generation* Aerodynamic lift is created as a result of the interaction between the airfoil and the incoming airflow. This force keeps the aircraft airborne and [can](/en/detay/can-3/llms.txt) be explained using two key principles: ##### **Bernoulli’s Principle** The shape of the airfoil causes differences in airflow speed across its surfaces: - **Upper Surface**: The convex curvature makes air travel faster, creating a lower-pressure zone. - **Lower Surface**: Slower airflow over the flatter surface results in higher pressure. This pressure differential produces lift, with the higher pressure underneath pushing the airfoil upward. ##### **Newton’s Third Law of Motion** The lower surface of the airfoil deflects airflow downward. According to Newton’s third law, this downward force creates an equal and opposite upward reaction, contributing to lift. ##### **Airfoil Dynamics During Takeoff** Several factors are crucial during an aircraft’s takeoff: - **Angle of Attack (AoA)**:The angle between the chord line and the incoming airflow. Increasing the AoA enhances lift but can lead to stall if the angle exceeds a critical point. - **Airflow Velocity**:As airspeed increases, more air passes over the wing, generating greater lift. This is why aircraft accelerate during takeoff. - **Wing Shape and Profile**:The airfoil’s thickness, camber, and surface area directly affect lift generation. ##### **Takeoff Process** 1. **Engine Thrust**: The aircraft’s engines accelerate it forward, increasing airflow over the wings. 2. **Angle of Attack Adjustment**: The pilot increases the AoA to generate more lift. 3. **Lift Generation**: The combination of airflow speed and AoA produces sufficient lift to counteract the aircraft’s weight. 4. **Takeoff**: When lift exceeds gravity, the aircraft leaves the ground. ## Academic Sources and References 1. "Kanat Profili (Airfoil) Nedir?" HavaUzay.org. Erişim Tarihi: 25 Ocak 2025. https://www.havauzay.org/kanat-profili-airfoil-nedir.html 2. "Why Do Airfoils Have Round Leading Edges and Sharp Trailing Edges?" Quora. Erişim Tarihi: 25 Ocak 2025. https://www.quora.com/Why-do-airfoils-have-round-leading-edges-and-sharp-trailing-edges