What effect does Foreign Object Damage have on the airstream?

What effect does Foreign Object Damage have on the airstream?

• A. It improves the aerodynamics
• B. It increases mechanical noise only
• C. It distorts the aerodynamic shape of the airfoil
• D. It compresses the inlet

Answer: (C)

Foreign Object Damage changes the surface geometry of the airfoil, spoiling the smooth contour the air must flow over. That distortion alters local camber and thickness, upsetting the pressure distribution and causing the boundary layer to separate earlier. The result is increased drag, reduced lift, and potential stall, all stemming from a distorted airstream around the airfoil. So the primary aerodynamic consequence is the distortion of the airfoil’s aerodynamic shape.

Foreign Object Damage changes the surface geometry of the airfoil, spoiling the smooth contour the air must flow over. That distortion alters local camber and thickness, upsetting the pressure distribution and causing the boundary layer to separate earlier. The result is increased drag, reduced lift, and potential stall, all stemming from a distorted airstream around the airfoil. So the primary aerodynamic consequence is the distortion of the airfoil’s aerodynamic shape.