What is the best rate of climb (Vy) speed?

The best rate of climb speed, referred to as Vy, is defined as the speed at which an aircraft gains the most altitude in the shortest amount of time. This speed is crucial during the climb phase after takeoff, as it allows the aircraft to clear obstacles safely and efficiently.

For many single-engine general aviation aircraft, such as the popular Cessna 172, the Vy speed is typically around 70 knots under normal conditions without any additional drag from flaps. The addition of flaps, such as extending them to a setting of 10 degrees, often requires a reduction in speed to optimize climb performance, which brings the Vy down to around 65 knots.

This understanding of Vy is fundamental for pilots, especially during training and checkrides, as it emphasizes the importance of maintaining the specified climb speed for safe and effective flight operations. The correct answer aligns with this principle, making it the most suitable choice based on typical aircraft performance data.