Question of the week: Lift/drag ratio

December 16, 2013

Question: The relationship between lift generated by a wing compared to its drag (L/D ratio) gives us valuable information about the wing's performance through a range of angles of attack. The angle of attack that gives the wing the maximum L/D ratio is known as L/DMAX. When operating an aircraft in steady flight at L/DMAX, is drag at a maximum?
Answer: No. When operating an aircraft at L/DMAX, total drag is at a minimum. See Chapter 4 of the Pilot’s Handbook of Aeronautical Knowledge. See this article for more facts about the L/D ratio.