What is a primary reason for flying high and fast in a jet?

Flying high and fast in a jet primarily contributes to increased fuel efficiency. At higher altitudes, the air is thinner, which reduces drag on the aircraft. This allows the jet to maintain speed while using less power, resulting in more efficient fuel consumption. Additionally, jets are designed to cruise at altitudes where the engines operate most efficiently, usually above weather systems and turbulence, further enhancing their performance.

The combination of altitude and speed allows for optimal aerodynamic performance. Aircraft can take advantage of the thinner atmosphere, which means they do not have to work as hard to overcome air resistance. This is crucial for long-haul flights where fuel efficiency can significantly impact operational costs.