Commercial jet aircraft operate in the lower stratosphere to avoid turbulence in the troposphere below. The stratosphere is very dry, with very little water vapor in the air. As a result, few clouds form in this layer; practically all clouds form in the lower, more humid troposphere. The altitude of the stratosphere varies depending on the location on Earth. It can be as low as 10 miles (16 km) at the equator where there is no wind to blow away moisture from the atmosphere, but it can also reach up to 50 miles (80 km) or more at high latitudes where there are strong winds.
The average altitude of the stratosphere is about 11 miles (18 km).
The plane's flight path takes it through both the troposphere and stratosphere, allowing it to travel long distances without refuelling. Aircraft engines burn large amounts of fuel when they first start up, so they need time to warm up properly. The trip from New York to London takes about 12 hours because the pilot allows the plane to cruise at a low altitude for most of the way to give it enough time to heat up and use less fuel.
The thinner the atmosphere, the more energy is needed to lift an object through it. For example, a helicopter needs much more power than a plane at the same altitude because it has to deal with both the troposphere and the stratosphere simultaneously.
The troposphere is the Earth's atmosphere's lowest level. However, above it is the stratosphere, which is followed by the stratopause and eventually the mesosphere. Commercial jets can fly above or below the troposphere, but this layer of the atmosphere provides optimum flight conditions for a variety of reasons. For example, air at ground level is compressed by surface friction so much that it becomes hot and dry. This is not so at high altitude where there is less pressure driving away moisture from the clouds.
Airplanes are capable of flying in all three layers of the atmosphere: the troposphere, the stratosphere and the mesosphere. The troposphere is important because most airports are located within its limits; also, weather occurs only in the troposphere. The stratosphere begins at about 10,000 feet (3,050 m) above sea level and extends up to 50,000 feet (15,000 m), although it is mainly between 20,000 and 30,000 feet (6,100 and 9,200 m) that significant atmospheric phenomena occur. The mesosphere starts at about 75,000 feet (23,500 m) and continues up to space where there is no atmosphere at all! It should be noted that aircraft cannot fly into space because there is nothing for them to hit - they would just keep going forever.
The troposphere is the largest layer of the Earth's atmosphere and accounts for more than 99% of its total mass.
The tropopause is the barrier between the troposphere and the stratosphere, and it is addressed in a separate article. Most light aircraft and turboprop aircraft fly in the troposphere, which contains the majority of the water vapour and so cloud formation. However, there are times when flights cross into the stratosphere, which has less moisture and no clouds.
The troposphere is the part of the Earth's atmosphere that lies directly above the surface. It extends from the sea level up to about 10-12 miles (16-19 km) altitude. The troposphere is divided into three distinct layers called the tropopause, tropopause layer, and tropopause hot spot.
The tropopause is the boundary between the troposphere and the stratosphere. It is approximately 10-11 miles (16-18 km) high and acts as a barrier for many atmospheric components, including moisture, ozone, and cosmic rays. Air flows across this layer from the tropics towards the poles where it is forced upwards by cold air sinking below it. This movement is responsible for most trade winds.
At the top of the troposphere is the tropopause layer. Its height varies depending on the location but is usually between 5,000 and 9,000 feet (1,524 and 2,443 m).
The troposphere is the lowest layer of the atmosphere and is where the bulk of weather occurrences occur on the globe. It reaches a height of around 36,000 feet. Helicopters and small planes generally travel in the troposphere.
The stratosphere begins at about 10 miles above sea level and extends up to 50 miles into space. It is a very thin layer of air but plays an important role in climate change. Weather phenomena such as hurricanes and tornados often develop in the stratosphere before falling back to earth. Aircraft usually do not fly in the stratosphere because it is too cold and there are no oxygen clouds that aircraft could crash into.
The troposphere comprises approximately 70 percent of the Earth's surface and it is where we live. It is made up of large areas of land and water that shape how weather affects us. The troposphere is also the layer where most global flights occur. Although airplanes can fly higher than this, most flights are done within the troposphere because that's where most people live and work.
The troposphere is divided into two main layers: the tropopause and the troposphere. The tropopause is the boundary between the troposphere and the surrounding atmosphere. It acts like a lid on the troposphere which prevents certain substances from entering or leaving it.
Planes often fly in the stratosphere, the earth's second primary layer of atmosphere. The reasons behind this are fairly practical and not difficult to comprehend. The stratosphere is a very stable region of the atmosphere with little turbulence or wind shear. Aircraft that operate in this region can expect steady conditions that are well-suited for flying.
The troposphere is the lowest part of the atmosphere where weather occurs. It starts at about 9 miles (15 km) above sea level and extends all the way down to the surface of the planet. Everything in between is called the hydrosphere. Airplanes typically do not fly in the troposphere because it is too turbulent. Instead they fly in the stratosphere, which is less turbulent than the troposphere but still has more structure than most airspace users would prefer for flying.
The thermosphere is the third layer of the Earth's atmosphere. It starts around 30 miles (50 km) up and goes all the way to space. The thermosphere is extremely dynamic with strong winds, intense radiation, and large-scale magnetic fields. These properties make it unsuitable for aircraft flight. Planes that enter the thermosphere usually do so accidentally when they pass through the region in connection with natural events like solar flares or volcanic eruptions.