What is drag?

What is drag?

• A. The forward force produced by engines
• B. The upward force generated by the wings
• C. The gravity acting on the aircraft
• D. Air resistance against the aircraft that tends to slow it down.

Answer: (D)

Drag is the air resistance that acts opposite to the airplane’s motion through the air, tending to slow the aircraft down. It’s one of the four aerodynamic forces, with thrust pushing forward, lift pushing upward, and weight pulling downward. Drag arises from the air itself as the aircraft moves: air molecules are pushed aside and create friction and pressure differences around the aircraft. In steady, level flight, the engines must provide enough thrust to overcome drag, so thrust equals drag and speed remains constant. Drag increases with speed and depends on the aircraft’s shape, surface roughness, and air density; smoother, sleeker designs with smaller frontal areas experience less drag.

Drag is the air resistance that acts opposite to the airplane’s motion through the air, tending to slow the aircraft down. It’s one of the four aerodynamic forces, with thrust pushing forward, lift pushing upward, and weight pulling downward. Drag arises from the air itself as the aircraft moves: air molecules are pushed aside and create friction and pressure differences around the aircraft. In steady, level flight, the engines must provide enough thrust to overcome drag, so thrust equals drag and speed remains constant. Drag increases with speed and depends on the aircraft’s shape, surface roughness, and air density; smoother, sleeker designs with smaller frontal areas experience less drag.