Do planes fly in the troposphere?

Most clouds appear here, mainly because 99% of the water vapor in the atmosphere is found in the troposphere. Air pressure drops, and temperatures get colder, as you climb higher in the troposphere. Some commercial aircraft fly some of the time in the troposphere, because that is the altitude assigned to them. read more

Planes do not fly in Troposphere. They fly in Stratosphere. The above answer is not true.. Commercial airplanes do fly in Troposphere. Troposphere has the highest density, pressure of all regions . Commercial flights are flying at about 11000m which is about 30 000++ Ft. the temp drop is about 6.5 degree at every 1000 m. read more

Absolutely. Although the altitude of the tropopause (the lower boundary of the stratosphere) varies depending on latitude, jet airliners, cargo jets and military jets often fly in the stratosphere, since the thinner air causes less drag than the thicker air down in the troposphere. read more