Which force directly opposes lift in aviation?

In aviation, lift is the upward force that allows an aircraft to rise into the air and remain aloft. The force that directly opposes lift is weight, which is the downward force due to gravity acting on the mass of the aircraft. When an aircraft is in steady flight, lift must equal weight for the aircraft to maintain altitude. If lift exceeds weight, the aircraft will ascend; conversely, if weight exceeds lift, the aircraft will descend.

Understanding the relationship between lift and weight is crucial for pilots as they navigate different phases of flight, such as climb, cruise, and descent. The balance between these forces is fundamental in maintaining stable flight and ensuring safe operations.