In all problems, assume a sea-level ISA condition, unless otherwise stated. 6.1 6.2 An aircraft with a prop-driven 100 hp engine is flying at a speed of 120 knot. If the propeller generates 200 lb of thrust, determine the prop efficiency. The aircraft in Problem 6.1 has a mass of 1000 kg, a wing area of 15 m, and an induced drag factor of (K) 0.057. What is the maximum lift-to-drag ratio of this aircraft?