In jets, what does Vx represent?

Vx represents the speed at which an aircraft achieves the best angle of climb. This speed allows the aircraft to gain the most altitude over the shortest horizontal distance. At Vx, the aircraft's thrust available exceeds the thrust required, allowing for optimal climb performance.

Understanding why this speed is crucial can aid in a pilot's decision-making process, especially during takeoff and initial climb. Climbing at this speed ensures that the aircraft can clear any obstacles while minimizing horizontal distance covered.

The other options relate to different aspects of flight performance, but Vx is specifically focused on the best climb performance in terms of altitude gain relative to ground distance. This makes Vx a vital parameter for pilots, particularly when dealing with obstacles or in terrain-challenging environments during takeoff.