But just how high do planes fly? And why do they have to stay at a set altitude? We reached out to Theodore Kyrazis, a JetBlue captain and retired U.S. Air Force F-15 pilot, to find out.

The primary reason that jets don't exceed 50,000 feet on average is that fuel doesn't burn properly at high altitudes. That high above the ground, the oxygen in the air is very thin — jet fuel ...

But while it may feel like it's less safe to fly, the numbers show the opposite. Historical data demonstrates a clear and consistent trend. A 2024 study from MIT found it's roughly 40 times safer ...

Apart from this, private jets are better able to dodge bad weather due to their ability to fly at high altitudes. Commercial airliners flying in congested airspaces might find it harder to switch ...