Why do commercial planes fly at 35,000 feet?

Question

Why do commercial planes fly at 35,000 feet?

In: 13

Answer 1

1. Fuel efficiency, thin air means less drag. They can’t go too high or the engines can get enough oxygen from the thin air to burn as fuel.
2. Flying in the stratosphere (atmospheric layer) which starts at about 33000 feet in temperate latitudes, means flying above most weather which is in the lowest layer called the troposphere. That reduces turbulence at cruising altitude.

Answer 2

1. Fuel efficiency, thin air means less drag. They can’t go too high or the engines can get enough oxygen from the thin air to burn as fuel.
2. Flying in the stratosphere (atmospheric layer) which starts at about 33000 feet in temperate latitudes, means flying above most weather which is in the lowest layer called the troposphere. That reduces turbulence at cruising altitude.