What generates interference drag?

Interference drag is generated by the interaction of multiple airstreams around various components of an aircraft, such as the wings, fuselage, and control surfaces. This type of drag occurs when the airflow produced by one surface interacts with the airflow from another surface, leading to disruptions in the smooth flow of air.

In the case of aircraft, when different parts are close together, such as the junction between the wing and the fuselage, the collision of airflow around these parts creates a turbulent region, which results in additional drag. This is a specific type of drag that occurs due to the geometric and aerodynamic configuration of the aircraft.

Understanding the causes of interference drag is crucial for aircraft design and performance optimization, as reducing this drag can lead to improved efficiency and overall aerodynamic performance. Other factors, such as surface roughness, may influence drag but do not specifically pertain to the interaction of airstreams as interference drag does. Likewise, altitude variation and aerofoil design relate to different aspects of aerodynamic efficiency and performance rather than specifically causing interference drag.