Which speed is described as the best angle-of-climb speed?

• A. VX
• B. VY
• C. VS0
• D. VNO

Answer: (A)

Best angle-of-climb speed is the airspeed at which the airplane climbs the steepest path, meaning the greatest altitude gain for each horizontal unit of distance traveled. At this speed, you have enough lift and thrust to keep climbing without increasing drag so much that the climb angle diminishes, and you avoid getting too close to stall. It’s intentionally lower than the speed for maximum rate of climb, which is about climbing as fast as possible in altitude per minute but not necessarily along the steepest path. The other options don’t maximize the ascent angle: the stall-speed reference is simply the minimum speed to stay airborne in the landing configuration, and the maximum structural cruising speed is about not exceeding airframe limits, neither of which define the steepest climb path. Thus, the steepest climb angle is achieved at the best angle-of-climb speed.