13800m
13800m refers to a specific altitude, measured in meters above sea level. This height is significant within the context of aviation and atmospheric science. Commercial airliners typically cruise at altitudes between 10,000m and 12,000m, placing 13,800m well above standard flight paths for passenger aircraft. At such an altitude, the air is considerably thinner, meaning there is less oxygen and atmospheric pressure. This makes sustained human presence without specialized equipment impossible.
The Karman line, often considered the boundary of space, is located at 100 kilometers (100,000m) above sea