What is the best glide speed at max weight?

• A. 119 knots
• B. 105 knots
• C. 125 knots
• D. 135 knots

Answer: (A)

Best glide speed is the airspeed at which the lift‑to‑drag ratio is maximized, so you can glide the farthest for a given altitude. In steady, unpowered flight, lift equals weight, and drag consists of induced drag (from generating lift) and parasite drag (which grows with speed). The total drag curve has a minimum at the speed where these two components balance. As weight increases, induced drag at a given speed increases, so the minimum-drag point shifts to a higher speed to offset that extra induced drag with less relative parasite drag. That’s why the best glide speed at maximum gross weight is higher than at lighter weights. For the PC‑12 NGX, about 119 knots bests the other options by aligning with that minimum-drag point at max weight, giving the greatest glide distance. Slower speeds would keep too much induced drag, while faster speeds would incur more parasite drag and reduce the glide distance.