ELI5: Explain Like I'm 5

Flight level

Okay kiddo, so when planes are flying they need to have a way to stay at a certain height so they don't bump into other planes or things on the ground. This is called their flight level.

Think of it like a big staircase in the sky. Each step is a different flight level and planes can fly on the step that they're assigned to by air traffic control. So, if a plane is told to fly at flight level 350, that means they're on the 35th step of the sky staircase.

The different flight levels are measured in feet above sea level, so flight level 350 means the plane is flying at 35,000 feet above the ocean.

Pilots use different instruments and equipment to make sure they stay at the right flight level and don't accidentally go too high or too low. This helps keep everyone safe and on the right path to their destination.
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