Air is a fluid. The interactions between the aircraft and the fluid it is surrounded in are important to analyze. Aerodynamics, a branch of fluid dynamics, deals only with air as a fluid. What is a vortex? How do wakes form? These are all questions that fluid dynamics can help answer.

• Boundary Layers - Formed close to the body of the aircraft.
• Wakes - Created by the passage of an aircraft through the air.

All interactions between the plane and the air can be analyzed and explained by fluid dynamics.