Which force opposes lift in flight?

In flight, drag is the force that opposes lift. Lift is generated by the wings of an aircraft as air flows over them, and it acts perpendicular to the direction of the airflow. However, as the aircraft moves through the air, it experiences drag, which is a resistance force that acts in the opposite direction to the aircraft's forward motion.

Drag is influenced by several factors, including the shape of the aircraft, its speed, and the density of the air. It is essential for pilots and engineers to consider drag when planning flights since it directly affects the aircraft's performance and fuel efficiency. Understanding drag helps in managing the balance between lift and weight to maintain controlled flight.

While weight does act against lift in the vertical direction, it is primarily the drag that counteracts the aircraft’s thrust and contributes to the overall challenge of maintaining altitude and speed during flight.