Drag is the force that acts in which direction relative to the flight path?

• A. Parallel to the flight path
• B. Perpendicular to the flight path
• C. At 45 degrees to the flight path
• D. Opposite to thrust direction

Answer: (A)

Drag is a resistive force that acts to oppose the airplane’s motion through the air. Its direction is along the line of the aircraft’s movement, i.e., parallel to the flight path, but opposite to the direction of travel. This is why drag slows you down as you move forward. It isn’t perpendicular to the flight path (that would describe lift’s direction relative to the air), and it isn’t at a diagonal angle. While drag is also opposite to thrust in the sense that thrust pushes forward and drag resists that forward push, the key point relative to the flight path is that drag lies along that path.